Final California 2018 Integrated Report (303(d) List/305(b) Report)

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 7 Basin Plan.

Objective/Criterion Reference:

Evaluation Guideline:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.

Guideline Reference:

Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013

Spatial Representation:

The samples were collected at station 715CRIDG1.

Temporal Representation:

The samples were collected in April 2008, October 2005, 2007 and 2008 and May 2007 and 2006.

Environmental Conditions:

QAPP Information:

Data quality is good. Data results were recorded in the SWAMP database and follwed SWAMP protocols.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 77980, Toxicity	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125394

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

3 of the 5 samples collected by SWAMP RWB7 Monitoring for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Young/female, Ceriodaphnia dubia, for Survival

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 stations. Monitoring site(s): ( 715CRIDG1, 715CRIDU1 )

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19.

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 77980, Toxicity	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125389

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 stations. Monitoring site(s): ( 715CRIDG1, 715CRIDU1 )

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19.

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 77980, Toxicity	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125406

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

1 of the 3 samples collected by SWAMP RWB7 Monitoring for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 stations. Monitoring site(s): ( 715CRIDG1 )

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11.

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 77980, Toxicity	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

31974

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Four samples were collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity test included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064

Spatial Representation:

The samples were collected at station 715CRIDG1.

Temporal Representation:

The samples were collected in April 2008 and May and October 2007.

Environmental Conditions:

QAPP Information:

Data quality is good. Data results were recorded in the SWAMP database and follwed SWAMP protocols.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 77980, Toxicity	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125396

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 stations. Monitoring site(s): ( 715CRIDG1 )

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11.

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70958	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1, 1-dichloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the California MCL. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70958, 1, 1-dichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34759

Pollutant:

1, 1-dichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 1-Dichloroethane is 5 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70958, 1, 1-dichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen water samples were generally collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

Surface Water Ambient Monitoring Program (SWAMP) Data for organic and inorganic constituents in water and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. May 2002-May 2005.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 1 mg/l Aluminum, 0.05 mg/l Arsenic, 0.0002 mg/l Benzo[a]Pyrene, 0.005 mg/l Cadmium, 0.0001 mg/l Chlordane, 0.05 mg/l Chromium, 0.6 mg/l o-Dichlorobenzene, 0.5 mg/l p-Dichlorobenzene, 0.005 mg/l 1,1-Dichloroethane, 0.006 mg/l 1,1-Dichloroethylene, 0.006 mg/l cis-1,2-Dichloroethylene, 0.01 mg/l 1,2-Dichloroethylene,-trans, 0.005 mg/l 1,2-Dichloropropane, 0.002 mg/l Endrin, 0.3 mg/l Ethylbenzene, 0.00001mg/l Heptachlor, 0.00001 mg/l Heptachlor Epoxide, 0.001 mg/l Hexachlorobenzene, 0.0002 mg/l Lindane/Hexachlorocyclohexane (HCH), 0.002 mg/l Mercury, 0.030 mg/l Methoxychlor, 0.013 mg/l Methly-Tertiary-Butyl Ether (MTBE), 0.02 mg/l Molinate, 0.070 mg/l Chlorobenzene (mono), 0.1 mg/l Nickel, 0.045 mg/l Nitrate, 0.001 mg/l Nitrite as N, 0.0005 mg/l PCBs (total), 0.05 mg/l Selenium, 0.005 mg/l Tetrachloroethylene, 0.07 mg/l Thiobencarb, 0.15 mg/l Toluene, 0.005 mg/l 1,2,4-Trichlorobenzene, 0.2 mg/l 1,1,1-Trichloroethane, 0.005 mg/l 1,1,2-Trichloroethane, 0.005 mg/l Trichloroethylene, and 1.75 mg/l Xylene (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Colorado River locations: downstream of Parker Dam, from three small associated lakes on the River (Ferguson, Taylor and Squaw), upstream of Imperial Dam, and at the Imperial Dam grates.

Temporal Representation:

Seventeen water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Imperial Dam grate location. Samples were usually collected in May and October. The rest of the locations were sampled in May and October 2002. An extra sample was collected from the upstream of Imperial Dam location in April 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70958, 1, 1-dichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128867

Pollutant:

1, 1-dichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 1-Dichloroethane is 0.005 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	78586	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1, 2-Dibromoethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Six samples were collected but were not used in the assessment because the laboratory data reporting limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78586, 1, 2-Dibromoethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127964

Pollutant:

1, 2-Dibromoethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dibromoethane, 1,2-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 2-Dibromoethane is 0.00005 mg/L (Title 22 of the California Code of Regulations ).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78586, 1, 2-Dibromoethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34729

Pollutant:

1, 2-Dibromoethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Two samples were collected but were not used in the assessment because the laboratory data reporting limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 2-Dibromoethane is 0.05 ug/L (Title 22 of the California Code of Regulations ).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104159	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,1,1,2-Tetrachloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 dissolved fraction water samples collected 2002-2005 exceeded the objective as no evaluation guideline for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. Four total fraction samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 104159, 1,1,1,2-Tetrachloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29489

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chloroform, Methylene Bromide, Bromochloromethane, Ethylene Dibromide, 1,1,1,2-Tetrachloroethane, 1,2,3,-Trichloropropane, 1,2-Dibromo 3-Chloropropane, 1,3-Dichloropropane, 2,2-Dichloropropane, or 1,1-Dichloropropene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Fifteen water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2004 from the Imperial Dam grate location. Samples were usually collected in May and October. The rest of the locations were sampled in May and October 2002. An extra sample was collected from the upstream of Imperial Dam location in April 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104159, 1,1,1,2-Tetrachloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128510

Pollutant:

1,1,1,2-Tetrachloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Tetrachloroethane, 1,1,1,2-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA Health Advisory for Tetrachloroethane, 1,1,1,2- as a drinking water level with a one in a million cancer risk is 0.001 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	71584	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,1,1-Trichloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of six total fraction and none of 17 dissolved fraction water samples exceeded the California MCL and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71584, 1,1,1-Trichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34724

Pollutant:

1,1,1-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 1, 1-Trichloroethane is 200 ug/L (Title 22 of the California Code of Regulations ).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71584, 1,1,1-Trichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71584, 1,1,1-Trichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128469

Pollutant:

1,1,1-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 1, 1-Trichloroethane is 0.2 mg/L (Title 22 of the California Code of Regulations ).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70901	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,1,2,2-Tetrachloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 11 water samples exceeded the California MCL. None of six water samples exceeded the California Toxics Rule Criteria. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70901, 1,1,2,2-Tetrachloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127929

Pollutant:

1,1,2,2-Tetrachloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Tetrachloroethane, 1,1,2,2-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2, 2-Tetrachloroethane criteria for the protection of human health from the consumption of water and organisms is 0.17 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70901, 1,1,2,2-Tetrachloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35670

Pollutant:

1,1,2,2-Tetrachloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2, 2-Tetrachloroethane criteria for the protection of human health from the consumption of water and organisms is 0.17 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70901, 1,1,2,2-Tetrachloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7669

Pollutant:

1,1,2,2-Tetrachloroethane | 1,2-Dichloroethane | Benzene | Carbon tetrachloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen samples were taken at 6 locations along this segment of the Colorado River. Six water sample results could not be used in this assessment because the sample results were non-detect and the detection limit was above the criteria concentration. The 11 acceptable water quality sample were collected from 10/2002 through 5/2005 at 6 locations. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.001 mg/l Benzene, 0.0005 mg/l Carbon Tetrachloride, 0.0005 mg/l 1,2-Dichloroethane, and 0.001 mg/l 1,1,2,2-Tetrachloroethane (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Seventeen water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Imperial Dam grate locations. Samples were usually collected in May and October. The rest of the locations were sampled in May and October 2002. An extra sample was collected from the upstream of Imperial Dam location in April 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70901, 1,1,2,2-Tetrachloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126979

Pollutant:

1,1,2,2-Tetrachloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2, 2-Tetrachloroethane criteria for the protection of human health from consumption of organisms only is 11 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70901, 1,1,2,2-Tetrachloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35649

Pollutant:

1,1,2,2-Tetrachloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2, 2-Tetrachloroethane criteria for the protection of human health from consumption of organisms only is 11 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates - 715CRIDG1]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70944	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,1,2-Trichloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. LOEs No. 27212 and 7649 are replaced by the LOEs No. 46761 and 7674, respectively, because LOE No. 27212 and 7649 were reassessed using updated criteria. None of samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of two total fraction water samples exceeded the CTR criteria for the "Municipal & Domestic Supply " beneficial use assessed. Four samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. None of 17 dissolved fraction and none of six total fraction water samples exceeded the CTR criteria for the "Commercial or recreational collection of fish, shellfish, or organisms" beneficial use assessed. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70944, 1,1,2-Trichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27212

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria for the protection of human health when consuming water and organisms from aquatic systems were used for the following constituents: 1.2 ug/l Benzene, 4.3 ug/l Bromoform, 0.25 ug/l Carbon Tetrachloride, 0.56 ug/l Dichlorobromomethane, 0.38 ug/l 1,2-Dichloroethane, 0.52 ug/l 1,2-Dichloropropane, 0.44 ug/l Hexachlorobutadiene, 0.80 ug/l Tetrachloroehtylene, 0.6 ug/l 1,1,2-Trichloroethane, and 2.7 ug/l Trichloroethylene (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70944, 1,1,2-Trichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46761

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen samples were taken at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria for the protection of human health when consuming organisms only from aquatic systems were used for the following constituents: 71 ug/l Benzene, 360 ug/l Bromoform, 46 ug/l Dichlorobromomethane, 99 ug/l 1,2-Dichloroethane, 39 ug/l 1,2-Dichloropropane, 50 ug/l Hexachlorobutadiene, 8.85 ug/l Tetrachloroehtylene, 42 ug/l 1,1,2-Trichloroethane, and 81 ug/l Trichloroethylene (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70944, 1,1,2-Trichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7649

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70944, 1,1,2-Trichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127692

Pollutant:

1,1,2-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2-Trichloroethane criteria for the protection of human health from consumption of organisms only is 42 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70944, 1,1,2-Trichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34741

Pollutant:

1,1,2-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2-Trichloroethane criteria for the protection of human health from consumption of organisms only is 42 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70944, 1,1,2-Trichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127942

Pollutant:

1,1,2-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Trichloroethane, 1,1,2-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2-Trichloroethane criteria for the protection of human health from the consumption of water and organisms is 0.60 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70944, 1,1,2-Trichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34757

Pollutant:

1,1,2-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2-Trichloroethane criteria for the protection of human health from the consumption of water and organisms is 0.60 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70944, 1,1,2-Trichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70961	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,1-Dichloroethylene (DCE)/ Vinylidene Chloride
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction water samples exceeded the California MCL. Six samples were collected but were not used in the assessment because the laboratory data reporting limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy. None of six total fraction water samples exceeded the California Toxics Tule Criteria. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70961, 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34792

Pollutant:

1,1-Dichloroethylene (DCE)/ Vinylidene Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1-Dichloroethylene criteria for the protection of human health from the consumption of water and organisms is 0.057ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70961, 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128904

Pollutant:

1,1-Dichloroethylene (DCE)/ Vinylidene Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichloroethylene, 1,1-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1-Dichloroethylene criteria for the protection of human health from the consumption of water and organisms is 0.057ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70961, 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128873

Pollutant:

1,1-Dichloroethylene (DCE)/ Vinylidene Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1-Dichloroethylene criteria for the protection of human health from consumption of organisms only is 3.2 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70961, 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34776

Pollutant:

1,1-Dichloroethylene (DCE)/ Vinylidene Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1-Dichloroethylene criteria for the protection of human health from consumption of organisms only is 3.2 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70961, 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104202	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,2,3-Trichloropropane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 15 dissolved fraction water samples collected 2002-2004 exceeded the objective as no evaluation guidelines for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. Zero of zero samples collected in 2013 exceeded the California Maximum Contaminant Levels. The four samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104202, 1,2,3-Trichloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127064

Pollutant:

1,2,3-Trichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Trichloropropane, 1,2,3-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Basin Plan's \Chemical Constituents\" objective. The CA Primary MCL for Trichloropropane, 1,2,3- is 0.000005 ug/L"

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104202, 1,2,3-Trichloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29489

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	79866	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,2,4-Trichlorobenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the California MCL. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 79866, 1,2,4-Trichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79866, 1,2,4-Trichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34809

Pollutant:

1,2,4-Trichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The National Recommended Water Quality Criteria for 1,2,4-Trichlorobenzene is 70 ug/l for water and fish consumption.

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79866, 1,2,4-Trichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127209

Pollutant:

1,2,4-Trichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Trichlorobenzene, 1,2,4-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The National Recommended Water Quality Criteria for 1,2,4-Trichlorobenzene is 0.076 ug/l for water and fish consumption.

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 79866, 1,2,4-Trichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127689

Pollutant:

1,2,4-Trichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1,2,4-Trichlorobenzene is 0.005 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 79866, 1,2,4-Trichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34813

Pollutant:

1,2,4-Trichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1,2,4-Trichlorobenzene is 5 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104203	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,2,4-Trimethylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objectives. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 dissolved fraction water samples collected 2002-2005 exceeded the objective as no evaluation guidelines for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. Zero of four total fraction water samples exceeded the California Department of Public Health (CDPH) notification level. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104203, 1,2,4-Trimethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128486

Pollutant:

1,2,4-Trimethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Deparment of Public Health (CDPH) notification level for 1,2,4-Trimethylbenzene is 330 ug/L.

Guideline Reference:

Drinking Water Notification Levels and Response Levels

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104203, 1,2,4-Trimethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128487

Pollutant:

1,2,4-Trimethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Deparment of Public Health (CDPH) notification level for 1,2,4-Trimethylbenzene is 330 ug/L.

Guideline Reference:

Drinking Water Notification Levels and Response Levels

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104203, 1,2,4-Trimethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29486

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104207	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,2-Dibromo-3-chloropropane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 dissolved fraction water samples collected 2002-2004 exceeded the objective as no evaluation guideline for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. Zero of zero total fraction water samples exceeded the California Maximum Contaminant Level. The six samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. LOE 127538 replaces LOE 127537 because they are duplicates. None of two water samples exceeded the California MCL for chloroform and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104207, 1,2-Dibromo-3-chloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29489

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104207, 1,2-Dibromo-3-chloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127537

Pollutant:

1,2-Dibromo-3-chloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dibromo-3-Chloropropane, 1,2-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 2-Dibromo-3-Chloropropane (DBCP) is 0.20 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104207, 1,2-Dibromo-3-chloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127538

Pollutant:

1,2-Dibromo-3-chloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dibromo-3-Chloropropane, 1,2-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 2-Dibromo-3-Chloropropane(DBCP) is 0.0002 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104207, 1,2-Dibromo-3-chloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34727

Pollutant:

1,2-Dibromo-3-chloropropane (DBCP)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 2-Dibromo-3-Chloropropane(DBCP) is 0.20 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70019	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,2-Dichloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. LOEs No. 27212 and 7669 are replaced by the LOE No. 46761 and 7649, respectively because they are assessed using the updated objective. None of samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and six total fraction water samples exceeded the CTR criteria for the "Commercial or recreational collection of fish, shellfish, or organisms" beneficial use assessed. None of 11 dissolved fraction and non of 2 total fraction water samples exceeded the CTR criteria for the "Municipal & Domestic Supply" beneficial use assessed. Ten total fraction samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70019, 1,2-Dichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128869

Pollutant:

1,2-Dichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloroethane criteria for the protection of human health from consumption of organisms only is 99 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70019, 1,2-Dichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127965

Pollutant:

1,2-Dichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichloroethane, 1,2-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloroethane criterion for the protection of human health from the consumption of water and organisms is 0.38 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70019, 1,2-Dichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34783

Pollutant:

1,2-Dichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloroethane criterion for the protection of human health from the consumption of water and organisms is 0.38 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70019, 1,2-Dichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46761

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen samples were taken at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70019, 1,2-Dichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7669

Pollutant:

1,1,2,2-Tetrachloroethane | 1,2-Dichloroethane | Benzene | Carbon tetrachloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70019, 1,2-Dichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34767

Pollutant:

1,2-Dichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloroethane criteria for the protection of human health from consumption of organisms only is 99 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70019, 1,2-Dichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7649

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70019, 1,2-Dichloroethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27212

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	79867	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,2-Dichloroethylene,-trans
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the California MCL. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 79867, 1,2-Dichloroethylene,-trans	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79867, 1,2-Dichloroethylene,-trans	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127763

Pollutant:

1,2-Dichloroethylene,-trans

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-trans-dichlorethylene criteria for the protection of human health from consumption of organisms only is 140,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 79867, 1,2-Dichloroethylene,-trans	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34819

Pollutant:

1,2-Dichloroethylene,-trans

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-trans-dichlorethylene criteria for the protection of human health from consumption of organisms only is 140,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79867, 1,2-Dichloroethylene,-trans	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127762

Pollutant:

1,2-Dichloroethylene,-trans

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for trans-1, 2-Dichloroethene is 0.01 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 79867, 1,2-Dichloroethylene,-trans	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34735

Pollutant:

1,2-Dichloroethylene,-trans

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for trans-1, 2-Dichloroethene is 10 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104213	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,3,5-Trimethylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 dissolved fraction samples colleced 2002-2004 exceeded the objective as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. Zero of four total fraction samples exceeded the Division of Drinking Water Notification Level. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104213, 1,3,5-Trimethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29486

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104213, 1,3,5-Trimethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128490

Pollutant:

1,3,5-Trimethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Drinking water notification levels are published by the Division of Drinking Water and are for chemicals for which there is no drinking water MCL. If a notification level is exceeded, local government notification is required and customer notification is recommended. The criteria for 1,3,5-Trimethylbenzene is 0.33 mg/L.

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104215	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	2-Chlorotoluene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 dissolved fraction samples colleced 2002-2004 exceeded the objective as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. Zero of four total fraction samples exceeded the USEPA's Drinking Water Health advisory. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104215, 2-Chlorotoluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29487

Pollutant:

2-Chlorotoluene | 4-Chlorotoluene | p-Cymene (p-Isopropyltoluene)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of 2-Chlorotoluene, 4-Chlorotoluene, or p-Cymene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104215, 2-Chlorotoluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

129003

Pollutant:

2-Chlorotoluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

USEPA's Drinking Water Health advisory for life-time exposure to o-chlorotoluene is a concentration of 100 ug/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104219	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	2-Methylnaphthalene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objectives. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 sediment samples and dissolved fraction water samples collected 2002-2004 exceeded the objective as no evaluation guideline for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. Zero of six total fraction water samples exceeded the USEPA expected safe lifetime exposure limit in drinking water. The sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104219, 2-Methylnaphthalene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127810

Pollutant:

2-Methylnaphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA expected safe lifetime exposure limit in drinking water for Methylnapthalene, 2-, calculated using the IRIS Reference Dose, is 28 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.004 mg/kg/day as the reference dose.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104219, 2-Methylnaphthalene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29547

Pollutant:

1-Methylnaphthalene | 2,3,5-Trimethylnaphthalene | 2,6-Dimethylnaphthalene | 2-Methylnaphthalene | Acenaphthylene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Acenaphthylene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Fifteen sediment samples were collected. Sediment samples were generally collected and analyzed biannually from 5/2002 through 5/2004 from the Imperial Dam grate location. Samples were usually collected in May and October from the Imperial Dam grate location. No sample was collected from the Imperial Dam grate location in April of 2003. The rest of the locations were sampled in May and October of 2002. An extra sample was collected from the upstream of Imperial Dam location in April of 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104219, 2-Methylnaphthalene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29492

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Acenaphthylene, Naphthalene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104220	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	4-Chlorotoluene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 dissolved fraction water samples collected 2002-2004 exceeded the objective as no evaluation guideline for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. Zero of four total fraction water samples exceeded the USEPA expected safe lifetime exposure limit in drinking water. The sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104220, 4-Chlorotoluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

129004

Pollutant:

4-Chlorotoluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

USEPA's Drinking Water Health advisory for life-time exposure to p-chlorotoluene is a concentration of 100 ug/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104220, 4-Chlorotoluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29487

Pollutant:

2-Chlorotoluene | 4-Chlorotoluene | p-Cymene (p-Isopropyltoluene)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of 2-Chlorotoluene, 4-Chlorotoluene, or p-Cymene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70213	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Acenaphthene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and non of 5 total fraction water samples exceeded California Toxics Rule criteria protecting human health when consuming water and organisms from these waters. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70213, Acenaphthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127707

Pollutant:

Acenaphthene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Acenaphthene criteria for the protection of human health from consumption of organisms only is 2,700 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70213, Acenaphthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen water samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria for the protection of human health when consuming water and organisms from aquatic systems were used for the following constituents: 1200 ug/l Acenaphthene, 0.0093 ug/l alpha-BHC, 110 ug/l alpha-Endosulfan, 9600 ug/l Anthracene, 0.014 ug/l beta-BHC, 110 ug/l beta-Endosulfan, 680 ug/l Chlorobenzene, 1300 ug/l Copper, 2700 ug/l o-Dichlorobenzene, 400 ug/l m-Dichlorobenzene, 400 ug/l p-Dichlorobenzene, 110 ug/l Endosulfan Sulfate, 0.76 ug/l Endrin, 0.76 Endrin Aldehyde, 3100 ug/l Ethylbenzene, 300 ug/l Fluoranthene, 1300 ug/l Fluorene, 0.050 ug/l Mercury, 610 ug/l Nickel, 960 ug/l Pyrene,and 6800 ug/l Toluene (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70213, Acenaphthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70213, Acenaphthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128823

Pollutant:

Acenaphthene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Acenaphthene criteria for the protection of human health from the consumption of water and organisms is 1,200 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	71594	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Aldrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.5 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of ten total fraction water samples exceeded the CTR criteria. None of seven fish tissue samples exceeded NAS guidelines. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34821

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Six samples were collected but were not used in the assessment because the laboratory data reporting limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Aldrin criteria for the protection of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127467

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Aldrin criterion maximum concentration to protect aquatic life in freshwater is 3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128912

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Aldrin criteria for the protection of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128911

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34805

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127456

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The aldrin criterion maximum concentration to protect aquatic life in freshwater is 3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126287

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Aldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126638

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45993

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126637

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34825

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Aldrin criterion maximum concentration to protect aquatic life in freshwater is 3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7634

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criterion Maximum Concentrations (CMCs) for the protection of freshwater aquatic life uses were used for the following constituents: 3 ug/l Aldrin, 0.22 ug/l alpha-Endosulfan, 340 ug/l Arsenic, 0.22 ug/l beta-Endosulfan, 2.4 ug/l Chlordane 1724 ug/l Chromium, 0.24 ug/l Dieldrin, 0.086 ug/l Endrin, 0.52 ug/l Heptachlor, and 0.52 Heptachlor Epoxide (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71594, Aldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126289

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104228	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Alkalinity as CaCO3
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2, a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of ten sample(s) exceed the criteria for the protection of freshwater aquatic life (National Recommended Water Quality Criteria, 2009) for the "Cold Freshwater Habitat" beneficial use assessed. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of ten sample(s) exceed the criteria for the protection of freshwater aquatic life (National Recommended Water Quality Criteria, 2009). This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples is needed to determine if a beneficial use is fully supported using table 3.2 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104228, Alkalinity as CaCO3	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128990

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The Alkalinity as CaCO3 criteria for the protection of freshwater aquatic life is 20000 ug/L (National Recommended Water Quality Criteria, 2009).

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70956	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Aluminum
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 water samples exceeded the California Primary MCL. None of 33 water samples exceeded the California Secondary MCL. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70956, Aluminum	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35178

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The California Secondary MCL for aluminum is 0.2 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR title 22 section 64449.

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70956, Aluminum	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7679

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance were used for the following constituents: 0.2 mg/l Aluminum, 500 mg/l Chloride, 1 mg/l Copper, 0.05 mg/l Manganese, 0.005 mg/l MTBE, 0.1 mg/l Silver, 500 mg/l Sulfate, 0.001 mg/l Thiobencarb, and 5 mg/l Zinc (CCR, title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70956, Aluminum	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70956, Aluminum	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126987

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for aluminum is 0.2 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104406	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Ametryn
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29501 received a use rating of insufficient in a previous assessment cycle because no evaluation guideline was available for this pollutant. None of the samples exceeded the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of three water samples exceeded the USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level. None of 14 dissolved fraction water samples collected years 2002-2004 exceeded the guideline as no evaluation guidelines for the dissolved fractions of Ametryn for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. The sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104406, Ametryn	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128481

Pollutant:

Ametryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104406, Ametryn	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29501

Pollutant:

Ametryn | Prometryn | Simetryn | Terbutryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fourteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ametryn, Prometryn, Simetryn, or Terbutryn for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Fourteen water samples were collected. Water samples were generally collected and analyzed from 5/2002 through 5/2004 from the Imperial Dam grate location. No samples were collected in 2003 from this location. Samples were usually collected in May and October. The rest of the locations were sampled in May and October 2002. An extra sample was collected from the upstream of Imperial Dam location in April 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	78334	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Ammonia
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 13 total fraction and zero of one dissolved fraction water samples exceeded the USEPA Temperature and pH-Dependent values of the CCC. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78334, Ammonia	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128528

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2010-10-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78334, Ammonia	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128539

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as \the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure.\""

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2010-10-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78334, Ammonia	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128545

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2010-10-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78334, Ammonia	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34571

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 5 samples exceed the water USEPA Temperature and pH-Dependent values of the CCC (Chronic Criterion) for Fish Early Life Stages Present for ammonia. 3 of the 5 data samples are reported as Non-Detect (ND). These 3 ND values are less than or equal to the water quality standard, the value will be considered as meeting the water quality standard, objective, criterion, or evaluation guideline.

Data Reference:

1999 Update of Ambient Water Quality Criteria for Ammonia

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Colorado River Basin Region (RWQCB 2006): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. There is no water quality objective for ammonia in the Water Quality Control Plan, Colorado River Basin. Instead, the USEPA criteria for ammonia was used as Temperature and pH-Dependent Values of the CCC (Chronic Criterion)for Fish Early Life Stages Present.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Sample was collected at 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78334, Ammonia	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128404

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2011-10-11 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78334, Ammonia	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128403

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2011-10-11 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78334, Ammonia	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128546

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2011-10-11 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70457	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Anthracene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27211 is replaced by the LOE No. 46763. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the California Toxics Rule criteria protecting human health when consuming water and organisms from these waters. None of 3 sediment samples exceeded the sediment quality guideline. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70457, Anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128142

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Anthracene criteria for the protection of human health from consumption of organisms only is 110,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70457, Anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125880

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan, Colorado River Basin)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Anthrazene is 845 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70457, Anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria for the protection of human health when consuming organisms only from aquatic systems were used for the following constituents: 2700 ug/l Acenaphthene, 0.013 ug/l alpha-BHC, 240 ug/l alpha-Endosulfan, 110000 ug/l Anthracene,0.046 ug/l beta-BHC, 240 ug/l beta-Endosulfan, 21000 ug/l Chlorobenzene, 17000 ug/l o-Dichlorobenzene, 2600 ug/l m-Dichlorobenzene, 2600 ug/l p-Dichlorobenzene, 240 ug/l Endosulfan Sulfate, 0.81 ug/l Endrin, 0.81 ug/l Endrin Aldehyde, 29000 ug/l Ethylbenzene, 370 ug/l Fluoranthene, 14000 ug/l Fluorene, 0.051 ug/l Mercury, 4600 ug/l Nickel, 11000 ug/l Pyrene,and 200000ug/l Toluene (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70457, Anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128141

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Anthracene criteria for the protection of human health from the consumption of water and organisms is 9,600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70457, Anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70457, Anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70457, Anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125485

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Anthrazene is 845 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104413	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Antimony
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 38 dissolved fraction and none of 38 total fraction water samples exceeded the California Maximum Contaminant Level. None of 3 sediment samples exceeded the sediment quality guideline. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 104413, Antimony	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125919

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 38 samples exceeded the water quality standard for Antimony.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for antimony is 0.006 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 104413, Antimony	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126072

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for antimony is 0.006 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 104413, Antimony	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126080

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Antimony criteria for the protection of human health from consumption of organisms only is 4300 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 104413, Antimony	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126099

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Antimony criteria for the protection of human health from consumption of organisms only is 4300 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.


DECISION ID	70907	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Arsenic
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1, 3.5 and 3.6 of the Listing Policy. Under sections 3.1 and 3.5 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Nineteen lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One composite fish tissue sample was collected, but not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy. None of 25 sediment samples exceeded the sediment quality guideline. None of 38 total fraction water samples (collected 11/2010-6/2016) exceeded the California MCL of 10 ppb. None of 17 dissolved fraction water samples (collected 5/2002-5/2005 exceeded the California MCL of 50 ppb. None of 54 dissolved fraction water samples (collected 10/2005-06/2016) exceeded the California MCL of 10 ppb. (Thirty-eight of the 54 dissolved fraction samples dates and locations overlapped with the total fraction water samples.) These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7634

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127070

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126027

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127071

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35196

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125932

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35223

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126074

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127073

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45994

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Arsenic. One composite (6 fish per composite) were generated from one species: largemouth bass. One sample was not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for arsenic in fish tissue is 0.0034 ppm. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. It is assumed that 10% of the total arsenic is present as inorganic arsenic. This constituent is a carcinogen therefore the risk level is set to one in a million.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125425

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Arsenic from MacDonald et al., 2000a which states that the probable effect concentration for Arsenic is 33 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125499

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Arsenic from MacDonald et al., 2000a which states that the probable effect concentration for Arsenic is 33 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35199

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125959

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126039

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125937

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Consensus Based Sediment Quality Guideline Probable Effects Concentrations (PECs) for the protection of freshwater organisms to toxic effects were used for the following constituents: 33 mg/kg Arsenic, 1050 ug/kg Benz[a]anthrazene, 4.98 mg/kg Cadmium, 111 mg/kg Chromium, 1290 ug/kg Chrysene, 149 mg/kg Copper, 61.8 ug/g Dieldrin, 207 ug/kg Endrin, 2230 ug/kg Fluoranthene, 536 ug/kg Fluorene, 128 mg/kg Lead, 4.99 ug/kg Lindane/Hexachlorocyclohexane (HCH), 1.06 mg/kg Mercury, 561 ug/kg Naphthalene, 48.6 mg/kg Nickel, 1170 ug/kg Phenanthrene, 676 ug/kg PCBs (Polychlorinated biphenyls), and 1520 ug/kg Pyrene (Macdonald et al, 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Seventeen sediment samples were collected. Sediment samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Imperial Dam grate locations. Samples were usually collected in May and October. The rest of the locations were sampled in May and October 2002. An extra sample was collected from the upstream of Imperial Dam location in April 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70907, Arsenic	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7685

Pollutant:

Arsenic | Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

United State Fish and Wildlife Service (USFWS) Biological Effect Criteria for the protection of aquatic life uses were used for the following constituents: 0.25 mg/l Arsenic, and 15 mg/l Copper (USFWS, 1998).

Guideline Reference:

Guidelines for Interpretation of the Biological Effect of Selected Constituents in Biota, Water, and Sediment. US Department of Interior report.

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70848	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Atrazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 16 dissolved fraction and none of 9 total fraction water samples exceeded the drinking water MCL and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70848, Atrazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35245

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Atrazine is 1 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70848, Atrazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7672

Pollutant:

Atrazine | Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Sixteen water samples were generally collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Sixteen water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Imperial Dam grate location. Samples were usually collected in May and October. No samples were collected from the Imperial Dame grate location in 2003. The rest of the locations were sampled in May and October 2002. An extra sample was collected from the upstream of Imperial Dam location in April 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 70848, Atrazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35266

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental phyusiological responses in human, plant, animal, or indigenous aquatic life. (Colorado River Basin)

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Atrazine is 43 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 70848, Atrazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127270

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 70848, Atrazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127269

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Atrazine is 0.001 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70848, Atrazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128624

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	104297	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Azinphos-methyl (Guthion)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29495 received a use rating of insufficient in a previous assessment cycle because no evaluation guideline was available for this pollutant. However, an evaluation guideline for Azinphos-methyl (Guthion) is available in later cycles, but results could not be quantified with the level of certainty required by the Listing Policy. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. LOE No. 29495 - Zero of 15 samples exceeded the guideline as no evaluation guideline was available for this pollutant. However, an evaluation guideline for Azinphos-methyl (Guthion) is available in later cycles, but results could not be quantified with the level of certainty required by the Listing Policy. Nine water samples were collected for Azinphos Methyl (Guthion), but the results were not used in the assessment because the laboratory data reporting limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104297, Azinphos-methyl (Guthion)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128924

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) expressed as a 4-day average for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104297, Azinphos-methyl (Guthion)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35308

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 104297, Azinphos-methyl (Guthion)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128217

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) expressed as a 4-day average for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104297, Azinphos-methyl (Guthion)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29495

Pollutant:

Azinphos, Ethyl (Ethyl Guthion) | Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Azinphos, methyl, or Azinphos, ethyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104298	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Barium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 38 samples exceeded the California Maximum Contaminant Level. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 104298, Barium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126103

Pollutant:

Barium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for barium is 1 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.


DECISION ID	79507	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Benzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27212 is replaced by the LOE No. 46761 because it was reassessed using the updated water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the CTR criteria. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 79507, Benzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34995

Pollutant:

Benzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Benzene is 1 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79507, Benzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128070

Pollutant:

Benzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzene criteria for the protection of human health from consumption of organisms only is 71 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 79507, Benzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35356

Pollutant:

Benzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzene criteria for the protection of human health from consumption of organisms only is 71 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79507, Benzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46761

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen samples were taken at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79507, Benzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7649

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79507, Benzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27212

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79507, Benzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127710

Pollutant:

Benzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Benzene. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Benzene is 0.001 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70458	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Benzo(a)anthracene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Eight lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 24 sediment samples exceeded the sediment quality guideline. None of six total fraction and none of 11 dissolved fraction water samples exceed CTR criteria. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70458, Benzo(a)anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128495

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Benz(a)anthracene. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzo(a)anthracene criterion for the protection of human health from the consumption of water and organisms is 0.0044 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-05-10 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70458, Benzo(a)anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128065

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzo(a)anthracene criteria for the protection of human health from consumption of organisms only is 0.049 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70458, Benzo(a)anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125518

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Benz[a]anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Benz[a]anthrazene is 1050 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70458, Benzo(a)anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35331

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Benzo(a)anthracene is 1050 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70458, Benzo(a)anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125836

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Benz[a]anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Benz[a]anthrazene is 1050 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70458, Benzo(a)anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70458, Benzo(a)anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7662

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria for the protection of human health when consuming organisms from aquatic systems were used for the following constituents: Benzene, 0.049 ug/l Benzo[a]Anthracene, 0.049 ug/l Benzo[a]Pyrene, 0.049 Benzo[b]Fluoranthene, 0.049 ug/l Benzo[k]Fluoranthene, 4.4 ug/l Carbon Tetrachloride, 0.049 ug/l Chrysene, 0.049 ug/l Dibenzo(a,h)Anthracene, 3.2 ug/l 1,1-Dichloroethylene, 0.049 ug/l Indeno(1,2,3-cd) Pyrene, and 11 ug/l 1,1,2,2-Tetrachloroethane (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70458, Benzo(a)anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127446

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Benz(a)anthracene. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzo(a)anthracene criteria for the protection of human health from the consumption of water and organisms is 0.0044 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-05-10 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	79917	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Benzo(a)pyrene (3,4-Benzopyrene -7-d)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Seven lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 24 sediment samples exceeded the sediment quality guideline. None of 17 dissolved fraction water samples exceeded the California MCLs. None of six total fraction water samples exceeded CTR criteria. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 79917, Benzo(a)pyrene (3,4-Benzopyrene -7-d)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125653

Pollutant:

Benzo(a)pyrene (3,4-Benzopyrene -7-d)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Benzo[a]pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Benzo[a]pyrene is 1450 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 79917, Benzo(a)pyrene (3,4-Benzopyrene -7-d)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35181

Pollutant:

Benzo(a)pyrene (3,4-Benzopyrene -7-d)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Benzo(a)Pyrene is 1450 ug/Kg dry weight (Macdonald et al. 2000)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 79917, Benzo(a)pyrene (3,4-Benzopyrene -7-d)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7623

Pollutant:

Benzo(a)pyrene (3,4-Benzopyrene -7-d)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Consensus Based Sediment Quality Guideline Probable Effects Concentration (PEC) of 1450 ug/kg for the protection of freshwater organisms to toxic effects (Macdonald et al, 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79917, Benzo(a)pyrene (3,4-Benzopyrene -7-d)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127074

Pollutant:

Benzo(a)pyrene (3,4-Benzopyrene -7-d)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzo(a)Pyrene criteria for the protection of human health from consumption of organisms only is 0.049 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 79917, Benzo(a)pyrene (3,4-Benzopyrene -7-d)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128893

Pollutant:

Benzo(a)pyrene (3,4-Benzopyrene -7-d)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Benzo(a)pyrene. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzo(a)Pyrene criteria for the protection of human health from the consumption of water and organisms is 0.0044 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-05-10 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 79917, Benzo(a)pyrene (3,4-Benzopyrene -7-d)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125544

Pollutant:

Benzo(a)pyrene (3,4-Benzopyrene -7-d)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Benzo[a]pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Benzo[a]pyrene is 1450 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 79917, Benzo(a)pyrene (3,4-Benzopyrene -7-d)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70206	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Benzo[b]fluoranthene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 11 dissolved fraction and none of six total fraction water samples exceeded the California Toxics Rule criteria. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 70206, Benzo[b]fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128335

Pollutant:

Benzo[b]fluoranthene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Benzo(b)fluoranthene. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzo(b)Flouranthene criteria for the protection of human health from the consumption of water and organisms is 0.0044 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-05-10 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70206, Benzo[b]fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7662

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70206, Benzo[b]fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127082

Pollutant:

Benzo[b]fluoranthene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzo(b)flouranthene criteria for the protection of human health from consumption of organisms only is 0.049 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	71645	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Benzo[k]fluoranthene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 11 dissolved fraction and none of six total fraction water samples exceeded the California Toxics Rule criteria. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 71645, Benzo[k]fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128898

Pollutant:

Benzo[k]fluoranthene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Benzo(k)fluoranthene. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzo(k)Fluoranthene criteria for the protection of human health from the consumption of water and organisms is 0.0044 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-05-10 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71645, Benzo[k]fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127839

Pollutant:

Benzo[k]fluoranthene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzo(k)Fluoranthene criteria for the protection of human health from consumption of organisms only is 0.049 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71645, Benzo[k]fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7662

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104301	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Beryllium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of five dissolved fraction and none of ten total fraction water samples exceeded the California Toxics Rule criteria. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104301, Beryllium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125940

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Beryllium.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for beryllium is 0.004 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-29 and 2016-03-30

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 104301, Beryllium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126026

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality standard for Beryllium.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for beryllium is 0.004 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2012-08-22 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.


DECISION ID	78634	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Bifenthrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Six lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of eight sediment samples exceeded the sediment quality guideline. One of four water samples exceeded the CTR criteria. Six sample results were not used in the assessment because the laboratory data reporting limit(s) was above the objective (0.0006 ug/L) and therefore the results could not be quantified with the level of certainty required by the Listing Policy. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78634, Bifenthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128675

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of bifenthrin does not exceed 0.0006 ug/L and if the 1-h average concentration does not exceed 0.004 ug/L. Mixtures of bifenthrin and other pyrethroids should be considered in an additive manner. (Fojut et al. 2012)

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78634, Bifenthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128676

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78634, Bifenthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125610

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78634, Bifenthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35418

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

NPDES Permit for Visalia.

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78634, Bifenthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125483

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78634, Bifenthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46350

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Bifenthrin. Six sample results were not used in the assessment because the laboratory data reporting limit(s) was above the objective (0.0006 ug/L) and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	104303	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Biphenyl
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	These pollutants are being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of six total fraction water samples exceeded the USEPA Integrated Risk Information System (IRIS) One-in-a-Million Incremental Cancer Risk Estimate for Drinking Water criteria. No evaluation guidelines for sediment or dissolved fraction water samples (collected 2002-2004) could be found that meet the requirements of section 6.1.3 of the Listing Policy. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104303, Biphenyl	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29500

Pollutant:

Benzo(e)Pyrene (4,5-benzopyrene) | Benzo[g,h,i]perylene | Biphenyl | Terbufos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, Biphenyl, or Terbufos for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104303, Biphenyl	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29576

Pollutant:

Benzo(e)Pyrene (4,5-benzopyrene) | Benzo[g,h,i]perylene | Biphenyl

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, or Biphenyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104303, Biphenyl	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127271

Pollutant:

Biphenyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA Health Advisory IRIS Reference Dose (RfD) as a drinking water level criteria for carbaryl is 4 ug/L.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	104307	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Bromobenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of four samples exceeded the USEPA's Drinking Water Health Advisory. Zero of 15 dissolved fraction water samples exceeded the guideline as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104307, Bromobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128761

Pollutant:

Bromobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

USEPA's Drinking Water Health Advisory - exposure limit for life-time exposure to Bromobenzen is a concentration of 0.06 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104307, Bromobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29486

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104308	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Bromochloromethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of two samples exceeded the USEPA's Drinking Water Health Advisory. Zero of 15 dissolved fraction water samples exceeded the guideline as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104308, Bromochloromethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29489

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104308, Bromochloromethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128762

Pollutant:

Bromochloromethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

USEPA's Drinking Water Health advisory for life-time exposure to Bromochloromethane is a concentration of 0.09 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70809	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Bromoform
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27212 is replaced by the LOE No. 46761 because it was reassessed using the updated objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of six total fraction and none of 17 dissolved fraction water samples exceeded the CTR criteria. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70809, Bromoform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27212

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70809, Bromoform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7649

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70809, Bromoform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46761

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen samples were taken at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70809, Bromoform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35206

Pollutant:

Bromoform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Bromoform criteria for the protection of human health from consumption of organisms only is 360 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70809, Bromoform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128765

Pollutant:

Bromoform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Bromoform criteria for the protection of human health from consumption of organisms only is 360 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70809, Bromoform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35227

Pollutant:

Bromoform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Bromoform criteria for the protection of human health from the consumption of water and organisms is 4.3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70809, Bromoform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128767

Pollutant:

Bromoform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Bromoform criteria for the protection of human health from the consumption of water and organisms is 4.3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70630	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Cadmium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1, 3.5 and 3.6 of the Listing Policy. Under sections 3.1 and 3.5 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Seventeen lines of evidence are available in the administrative record to assess this pollutant. LOE 7693 is replaced by LOE 7674 because it is assessed for a different guideline. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of one fish tissue sample exceeded the OEHHA fish contaminant goal. None of 25 sediment samples exceeded the sediment quality guideline. None of 44 dissolved fraction water samples and none of 3 total fraction water samples exceeded the California MCLs. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35249

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125799

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Cadmium from MacDonald et al., 2000a which states that the probable effect concentration for Cadmium is 4.98 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45995

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for cadmium in fish tissue is 2.2 ppm. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125971

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality standard for Cadmium.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-29 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128815

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7631

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Hardness Dependant Criterion Maximum Concentration (CMC) for the protection of freshwater aquatic life uses (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Fifteen water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Imperial Dam grate locations. Samples were usually collected in May and October. The rest of the locations were sampled in May and October 2002. An extra sample was collected from the upstream of Imperial Dam location in April 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126085

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality standard for Cadmium.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for cadmium in the Basin Plan is 0.005 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-29 and 2016-03-30

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35229

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for cadmium in the Basin Plan is 0.005 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128813

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for cadmium in the Basin Plan is 0.005 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7693

Pollutant:

Cadmium | Lead | Lindane/gamma Hexachlorocyclohexane (gamma-HCH) | Methoxychlor | Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the following limits: 10 ug/l Cadmium, 50 ug/l Lead, 4 ug/l Lindane/Hexachlorocyclohexane (HCH), 100 ug/l Methoxychlor, and 50 ug/l Silver (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32834

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples exceeded the hardness based criteria calculated for cadmium.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126129

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Cadmium.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for cadmium in the Basin Plan is 0.005 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2012-02-16 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125561

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Cadmium from MacDonald et al., 2000a which states that the probable effect concentration for Cadmium is 4.98 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127088

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70630, Cadmium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125997

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality standard for Cadmium.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-29 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.


DECISION ID	71008	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Carbon tetrachloride
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. LOE No. 7649 is replaced by LOE No. 7669. LOE No. 27212 is replaced by LOE No. 46762. None of other samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 11 dissolved fraction and none of two total fraction water samples exceeded the California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Level (MCL) for the protection of human health. Four total fraction samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. The sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 71008, Carbon tetrachloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35273

Pollutant:

Carbon tetrachloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Carbon tetrachloride criteria for the protection of human health from consumption of organisms only is 4.4 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71008, Carbon tetrachloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128880

Pollutant:

Carbon tetrachloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Carbon tetrachloride criteria for the protection of human health from consumption of organisms only is 4.4 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71008, Carbon tetrachloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46762

Pollutant:

Carbon tetrachloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria for the protection of human health when consuming organisms only from aquatic systems were used for the following constituents: 4.4 ug/l Carbon Tetrachloride

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71008, Carbon tetrachloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27212

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71008, Carbon tetrachloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128900

Pollutant:

Carbon tetrachloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Carbon Tetrachloride. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Carbon tetrachloride is 0.0005 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71008, Carbon tetrachloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7669

Pollutant:

1,1,2,2-Tetrachloroethane | 1,2-Dichloroethane | Benzene | Carbon tetrachloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71008, Carbon tetrachloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35293

Pollutant:

Carbon tetrachloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Carbon tetrachloride is 0.5 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71008, Carbon tetrachloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7649

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104414	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Carbophenothion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of three total fraction samples exceeded the Division of Drinking Water Notification Level. Zero of 15 dissolved fraction water samples collected 2002-2004 exceeded the guideline as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104414, Carbophenothion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29493

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104414, Carbophenothion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128884

Pollutant:

Carbophenothion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	71537	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chlordane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1, 3.5 and 3.6 of the Listing Policy. Under sections 3.1 and 3.5 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Sixteen lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of seven sediment samples exceeded the sediment quality guideline. None of seven fish tissue sample exceeded the modified OEHHA fish tissue guideline. None of 4 total fraction water samples exceeded the California drinking water MCLs. Six non-detect samples were greater than the criteria and thus the data were not used in this assessment. None of 17 dissolved fraction water samples exceeded the California drinking water MCLs. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7634

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126572

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total Chlordane concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126313

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126392

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for total chlordane in fish tissue is 3.9 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45996

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlordane, Total. One composite (6 fish per composite) were generated from one species: Largemouth Bass. Total chlordane was calculated as the sum of the following chlordane isomers: cis- and trans-chlordane, cis- and trans-nonachlor, and oxychlordane.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126577

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126574

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46003

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlordane, Total. One composite (6 fish per composite) were generated from one species: Largemouth Bass. Total chlordane was calculated as the sum of the following chlordane isomers: cis- and trans-chlordane, cis- and trans-nonachlor, and oxychlordane.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126393

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125574

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32849

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 4 samples collected for Chlordane (Sum of trans-Chlordane, cis-Chlordane, cis-Nonachlor, trans-Nonachlor, and Oxychlordane) exceeded the evaluation guideline.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Probable Effect Concentration for Chlordane in freshwater sediments is 17.6 ug/kg.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following station: Colorado River at Imperial Dam Grates - 715CRIDG1.

Temporal Representation:

The samples were collected on 10/25/2005 - 4/21/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125575

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33175

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The reporting limit for all 6 of the non-detect samples was greater than the criteria and thus the data were not used in this assessment.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The total chlordane criterion for the protection of human health from the consumption of water and organisms is 0.00057 ug/L. This value corresponds to total chlordane, eg., the sum of cis-chlordane, trans-chlordane, cis-nonachlor, trans-nonachlor, and oxychlordane. (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at station 715CRIDG1 Colorado River at Imperial Dam Grates

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127338

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The chlordane criteria for the protection of human health from the consumption of water and organisms is 0.00057 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71537, Chlordane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33225

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples exceeded the criterion continuous concentration for chlordane (total). Total chlordane is assessed as the sum of cis-chlordane, trans-chlordane, cis-nonachlor, trans-nonachlor, and oxychlordane.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at station 715CRIDG1 Colorado River at Imperial Dam Grates

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	104415	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chlordane, cis
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Although a total of 4 water samples were collected, the samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the zero samples exceeded DTR criteria. Although a total of 4 water samples were collected, the samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104415, Chlordane, cis	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128344

Pollutant:

Chlordane, cis

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlordane, cis-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The chlordane criteria for the protection of human health from the consumption of water and organisms is 0.00057 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104416	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chlordane, trans
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Although a total of 4 water samples were collected, the samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the zero samples exceeded DTR criteria. Although a total of 4 water samples were collected, the samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104416, Chlordane, trans	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127923

Pollutant:

Chlordane, trans

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlordane, trans-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The chlordane criteria for the protection of human health from the consumption of water and organisms is 0.00057 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70024	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chloride
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 67 dissolved fraction water samples exceeded the California secondary MCL. None of six total fraction water samples exceeded the criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater. This does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70024, Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128107

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Chloride criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 230000 ug/L (230 mg/L)(USEPA National Recommended Water Quality Criteria, 2006).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70024, Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33105

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples exceeded the criteria of 230 mg/L.

Data Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples were collected on 10/25/2005, 5/3/2006, 5/8/2007, 10/23/2007, 4/22/2008, and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 70024, Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126051

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 39 samples exceeded the water quality standard for Chloride.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2017-03-10

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70024, Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128106

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance were used: 500 mg/l Chloride (CCR, title 22).

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70024, Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125974

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 39 samples exceeded the water quality standard for Chloride.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance were used: 500 mg/l Chloride (CCR, title 22).

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2017-03-10

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70024, Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126043

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 39 samples exceeded the water quality standard for Chloride.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2017-03-10

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70024, Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128105

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70024, Chloride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7679

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	71174	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chlorobenzene (mono)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. LOE No. 7652 is replaced by the LOE No. 7674 and LOE No. 27211 is replaced by the LOE No. 46763 they assessed using the updated guidelines. None of other samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of 6 total fraction water samples exceeded the California Drinking Water Maximum Contaminant Level. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71174, Chlorobenzene (mono)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71174, Chlorobenzene (mono)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71174, Chlorobenzene (mono)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71174, Chlorobenzene (mono)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35334

Pollutant:

Chlorobenzene (mono)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for monochlorobenzene is 70 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71174, Chlorobenzene (mono)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128431

Pollutant:

Chlorobenzene (mono)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for monochlorobenzene is 0.07 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71174, Chlorobenzene (mono)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35314

Pollutant:

Chlorobenzene (mono)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Chlorobenzene criteria for the protection of human health from consumption of organisms only is 21,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71174, Chlorobenzene (mono)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128430

Pollutant:

Chlorobenzene (mono)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Chlorobenzene criteria for the protection of human health from consumption of organisms only is 21,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71174, Chlorobenzene (mono)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	77974	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chlorodibromomethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. LOE Nos. 128763, 128899 and 128462 are replaced by the LOE No. 127876. They re-assessed using the updated guideline or a duplicate. None of other samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 6 water samples exceeded the California Drinking Water Maximum Contaminant Level. None of 4 water samples exceeded the CTR criteria. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 77974, Chlorodibromomethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128462

Pollutant:

Chlorodibromomethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dibromochloromethane. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Chlorodibromomethane criteria for the protection of human health from the consumption of water and organisms is 0.401 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 77974, Chlorodibromomethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128763

Pollutant:

Chlorodibromomethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Bromodichloromethane incorporated by reference in the Basin Plan is The maximum contamination level safe for total trihalomethanes in drinking water is 0.08 mg/L (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 77974, Chlorodibromomethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127876

Pollutant:

Chlorodibromomethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Dibromochloromethane is The maximum contamination level safe for total trihalomethanes in drinking water is 0.08 mg/L (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 77974, Chlorodibromomethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35217

Pollutant:

Chlorodibromomethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dibromochloromethane criteria is 0.401 ug/L for the protection of human health from consumption of water and organisms (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 77974, Chlorodibromomethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128899

Pollutant:

Chlorodibromomethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bromodichloromethane. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dichlorobromomethane criteria for the protection of human health from the consumption of water and organisms is 0.56 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 77974, Chlorodibromomethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127877

Pollutant:

Chlorodibromomethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Chlorodibromomethane criteria for the protection of human health from consumption of organisms only is 34 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104417	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chloroform
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of six water samples exceeded the California MCL None of the dissolved fraction water samples exceeded the objective as no evaluation guidelines for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104417, Chloroform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29489

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104417, Chloroform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34998

Pollutant:

Chloroform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Chloroform criteria for the protection of human health from consumption of organisms only is 470 ug/L (The National Recommended Water Quality Criteria 2009).

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104417, Chloroform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127331

Pollutant:

Chloroform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Chloroform criteria for the protection of human health from consumption of fish only is 2000 ug/L (National Recommended Water Quality Criteria, 2015).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104417, Chloroform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35002

Pollutant:

Chloroform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for total trihalomethanes is 80 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104417, Chloroform	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127332

Pollutant:

Chloroform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for total trihalomethanes is 0.08 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	78172	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chlorpyrifos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1, 3.5, and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of one fish tissue sample exceeded the OEHHA fish contaminant goal. None of six sediment samples exceeded sediment quality guidelines. Six water were not used in the assessment because the laboratory data reporting limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy. These sample size are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78172, Chlorpyrifos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125505

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 3 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-05-10 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78172, Chlorpyrifos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35422

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78172, Chlorpyrifos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35190

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Six samples total were collected. None of the samples were not used in the assessment because the laboratory data reporting limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78172, Chlorpyrifos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127375

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.014 ug/L (Siepmann and Finlayson 2000).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78172, Chlorpyrifos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127931

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.014 ug/L (Siepmann and Finlayson 2000).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78172, Chlorpyrifos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

129061

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA drinking water health advisory for lifetime exposure to chlorpyrifos is 0.002 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78172, Chlorpyrifos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125820

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 3 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-05-10 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78172, Chlorpyrifos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46004

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for chlorpyrifos in fish tissue is 660 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104427	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chlorpyrifos, methyl
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of five total fraction samples exceeded the USEPA Aquatic Life Benchmark. Zero of 15 dissolved fraction water samples collected 2002-2004 exceeded the guideline as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104427, Chlorpyrifos, methyl	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127695

Pollutant:

Chlorpyrifos, methyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Chlorpyrifos Methyl is the USEPA Aquatic Life Benchmark of 0.085 ug/L for an invertebrate (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104427, Chlorpyrifos, methyl	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127870

Pollutant:

Chlorpyrifos, methyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Chlorpyrifos Methyl is the USEPA Aquatic Life Benchmark of 0.085 ug/L for an invertebrate (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104427, Chlorpyrifos, methyl	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29496

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos, Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70971	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chromium (total)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Eleven lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 8 sediment samples exceeded the sediment quality guideline. None of 33 dissolved fraction and none of 7 total fraction water samples exceeded the California MCL. None of 17 dissolved fraction water samples exceeded the CTR criterion maximum concentration. None of 16 dissolved fraction water samples exceeded the CTR criterion continuous concentration. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70971, Chromium (total)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70971, Chromium (total)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7634

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70971, Chromium (total)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35230

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70971, Chromium (total)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126083

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality standard for Chromium.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70971, Chromium (total)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128709

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70971, Chromium (total)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128711

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70971, Chromium (total)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34303

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples exceeded the MCL for total Chromium.

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Department of Public Health's Maximum Contaminate Level (MCL) in drinking water for Total Chromium is 0.05mg/L or 50ug/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at stations 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/05 and 10/29/08.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70971, Chromium (total)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33924

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples exceeded the hardness based criteria calculated for chromium III or the criteria for chromium VI.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each chromium III sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion. The criterion continuous concentration (4-day average) to protect aquatic life in freshwater for chromium VI is 11 ug/L and is not hardness dependent.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at stations 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/05 and 10/29/08.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70971, Chromium (total)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128710

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70971, Chromium (total)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125912

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Chromium from MacDonald et al., 2000a which states that the probable effect concentration for Chromium is 111 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70971, Chromium (total)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125490

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Chromium from MacDonald et al., 2000a which states that the probable effect concentration for Chromium is 111 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	71640	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chrysene (C1-C4)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. LOE 125415 is a duplicate of 125917. LOE 125625 is a duplicate of 125831. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 11 water samples exceeded the CTR criteria. Six samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. None of 7 sediment samples exceeded the sediment quality guideline. The sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 71640, Chrysene (C1-C4)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7662

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71640, Chrysene (C1-C4)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125625

Pollutant:

Chrysene (C1-C4)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Chrysene from MacDonald et al., 2000a which states that the probable effect concentration for Chrysene is 1290 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71640, Chrysene (C1-C4)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125831

Pollutant:

Chrysene (C1-C4)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Chrysene from MacDonald et al., 2000a which states that the probable effect concentration for Chrysene is 1290 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71640, Chrysene (C1-C4)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125415

Pollutant:

Chrysene (C1-C4)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Chrysene from MacDonald et al., 2000a which states that the probable effect concentration for Chrysene is 1290 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71640, Chrysene (C1-C4)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125917

Pollutant:

Chrysene (C1-C4)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Chrysene from MacDonald et al., 2000a which states that the probable effect concentration for Chrysene is 1290 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71640, Chrysene (C1-C4)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32869

Pollutant:

Chrysene (C1-C4)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 4 samples collected for Chrysene (Sum of c0-c3) exceeded the evaluation guideline.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Probable Effect Concentration for Chrysene in freshwater sediments is 1290 ug/kg.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following station: Colorado River at Imperial Dam Grates - 715CRIDG1.

Temporal Representation:

The samples were collected on 10/25/2005 - 4/21/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71640, Chrysene (C1-C4)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128988

Pollutant:

Chrysene (C1-C4)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chrysene. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Chrysene criteria for the protection of human health from the consumption of water and organisms is 0.0044 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-05-10 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104337	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Cinerin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of eight samples exceed the USEPA Aquatic Life Benchmark an invertebrate (chronic) for each type of Cinerin assessed: Cinerin-1 and Cinerin-2. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of eight samples exceed the USEPA Aquatic Life Benchmark an invertebrate (chronic) for each type of Cinerin assessed: Cinerin-1 and Cinerin-2. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104337, Cinerin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127366

Pollutant:

Cinerin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Cinerin-2 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104337, Cinerin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127365

Pollutant:

Cinerin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Cinerin-2 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104337, Cinerin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127351

Pollutant:

Cinerin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Cinerin-1 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104337, Cinerin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128039

Pollutant:

Cinerin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Cinerin-1 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	71590	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Copper
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Seventeen lines of evidence are available in the administrative record to assess this pollutant. LOE 7652 is replaced by LOE 7679 and LOE 7685 is replaced by LOE 7618 because they were re-assessed with a different objective. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 25 sediment samples exceeded the sediment quality guideline. None of eight total fraction water samples exceeded the California drinking water MCL. None of 38 dissolved fraction water samples exceeded the California drinking water MCL. None of 17 dissolved fraction water samples exceeded the CTR CMC. None of 28 dissolved fraction water samples exceeded the CTR CCC. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32898

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples exceeded the hardness based criteria calculated for copper.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7679

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7685

Pollutant:

Arsenic | Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Guidelines for Interpretation of the Biological Effect of Selected Constituents in Biota, Water, and Sediment. US Department of Interior report.

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128269

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126030

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality standard for Copper.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-29 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126006

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Copper.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-29 and 2011-08-23

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128270

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35276

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR title 22 section 64449.

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7618

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule Hardness Dependent Criterion Maximum Concentration (CMC) for the protection of freshwater aquatic life uses (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125947

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality standard for Copper.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-29 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128272

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125755

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Copper from MacDonald et al., 2000a which states that the probable effect concentration for Copper is 149 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125722

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Copper from MacDonald et al., 2000a which states that the probable effect concentration for Copper is 149 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35296

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for copper is 149 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125989

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality standard for Copper.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71590, Copper	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104407	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Coumaphos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Although a total of 3 samples were collected, the 3 samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Although a total of 3 samples were collected, the 3 samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. The sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104407, Coumaphos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127946

Pollutant:

Coumaphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Coumaphos. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Coumaphos is the USEPA Aquatic Life Benchmark of 0.0337 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104407, Coumaphos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128958

Pollutant:

Coumaphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Coumaphos. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Coumaphos is the USEPA Aquatic Life Benchmark of 0.0337 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	104428	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Cumene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of four total fraction samples exceeded the USEPA expected safe lifetime exposure limit in drinking water. Zero of 15 dissolved fraction water samples collected 2002-2004 exceeded the guideline as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104428, Cumene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127311

Pollutant:

Cumene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA expected safe lifetime exposure limit in drinking water for Isopropylbenzene, calculated using the IRIS Reference Dose, is 0.7 mg/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.1 mg/kg/day as the reference dose.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104428, Cumene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29486

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	78174	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Cyanazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of four water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 78174, Cyanazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35321

Pollutant:

Cyanazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Cyanazine is 4.8 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected on a single day 10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78174, Cyanazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127908

Pollutant:

Cyanazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Cyanazine is 4.8 ug/L.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78174, Cyanazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127906

Pollutant:

Cyanazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Cyanazine is 4.8 ug/L.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	78173	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Cyfluthrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Six lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of eight sediment samples exceeded the median lethal concentration (LC50) for Cyfluthrin. Ten water sample results were collected for each of these pollutants, but the results are not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4.Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 78173, Cyfluthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35430

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78173, Cyfluthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125753

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78173, Cyfluthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128942

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin, total. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of Cyfluthrin does not exceed 0.00005 ug/L.

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78173, Cyfluthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125877

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78173, Cyfluthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46373

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyfluthrin, total. Six sample results were not used in the assessment because the laboratory data reporting limit(s) was above the objective (0.00005 ug/L) and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of cyfluthrin does not exceed 0.00005 ug/L and if the 1-h average concentration does not exceed 0.0003 ug/L. Mixtures of cyfluthrin and other pyrethroids should be considered in an additive manner. (Fojut et al. 2012)

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78173, Cyfluthrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127916

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin, total. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of Cyfluthrin does not exceed 0.00005 ug/L.

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	78822	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Cyhalothrin, Lambda
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Six lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of eight sediment samples exceeded the median lethal concentration (LC50). Ten water sample results were collected for each of these pollutants, but the results are not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78822, Cyhalothrin, Lambda	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35445

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78822, Cyhalothrin, Lambda	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125609

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78822, Cyhalothrin, Lambda	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127971

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of lambda-cyhalothrin does not exceed 0.0005 ug/L. Mixtures of lambda-cyhalothrin and other pyrethroids should be considered in an additive manner. (Fojut et al. 2012)

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78822, Cyhalothrin, Lambda	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127972

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78822, Cyhalothrin, Lambda	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46334

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyhalothrin, lambda, total. Six sample results were not used in the assessment because the laboratory data reporting limit(s) was above the objective (0.0005 ug/L) and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of lambda-cyhalothrin does not exceed 0.0005 ug/L and if the 1-h average concentration does not exceed 0.001 ug/L. Mixtures of lambda-cyhalothrin and other pyrethroids should be considered in an additive manner. (Fojut et al. 2012)

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78822, Cyhalothrin, Lambda	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125614

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	78823	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Cypermethrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Eight lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 13 sediment samples exceeded the median lethal concentration (LC50). Ten water sample results were collected for each of these pollutants, but the results are not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy. LOE 127033 is replaced by LOE 128720. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78823, Cypermethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128720

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin, Total. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of cypermethrin does not exceed 0.0002 ug/L and if the 1-h average concentration does not exceed 0.001 ug/L. Mixtures of cypermethrin and other pyrethroids should be considered in an additive manner. (Fojut et al. 2012)

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78823, Cypermethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127033

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin, Total. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78823, Cypermethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127988

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin, Total. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78823, Cypermethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127989

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin, Total. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78823, Cypermethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125715

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).

Guideline Reference:

Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15

Spatial Representation:

Data were collected from 4 (Station Codes: 715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78823, Cypermethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35461

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78823, Cypermethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46364

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cypermethrin, total. Six sample results were not used in the assessment because the laboratory data reporting limit(s) was above the objective (0.0002 ug/L) and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78823, Cypermethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125862

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15

Spatial Representation:

Data were collected from 4 (Station Codes: 715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104433	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	DDD (Dichlorodiphenyldichloroethane)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Six lines of evidence are available in the administrative record to assess this pollutant. Six of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of seven sediment samples exceed probable effect concentration. None of four water samples exceed the CTR Criteria. Six non-detect samples was greater than the criteria: thus the data was not used in this assessment. this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104433, DDD (Dichlorodiphenyldichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125902

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104433, DDD (Dichlorodiphenyldichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32890

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 4 samples collected for Sum DDD exceeded the evaluation guideline.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Probable Effect Concentration for Sum DDD (o,p' + p,p') in freshwater sediments is 28.0 ug/kg.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following station: Colorado River at Imperial Dam Grates - 715CRIDG1.

Temporal Representation:

The samples were collected on 10/25/2005 - 4/21/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 104433, DDD (Dichlorodiphenyldichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125484

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104433, DDD (Dichlorodiphenyldichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128650

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The DDD(4,4') criteria for the protection of human health from consumption of organisms only is 0.00084 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104433, DDD (Dichlorodiphenyldichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34547

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The method detection limit for all 6 of the non-detect samples was greater than the criteria: thus the data was not used in this assessment.

Data Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 4,4'-DDD criterion for the protection of human health from the consumption of water and organisms is 0.00031 ug/L (USEPA Nationally Recommended Criteria, 2006).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at stations 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104433, DDD (Dichlorodiphenyldichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128652

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 4,4'-DDD criterion for the protection of human health from the consumption of water and organisms is 0.00083 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104434	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	DDE (Dichlorodiphenyldichloroethylene)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Seven lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceeded the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of seven sediment samples exceed probable effect concentration. None of four water samples exceed the CTR Criteria. The method detection limit for 6 additional water samples was non-detect, however the detection limit was greater than the criteria. Thus this data was not used in this assessment. None of 15 dissolved fraction water samples exceeded the guideline as no evaluation guideline for the dissolved fractions of o,p'-DDE for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. The sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104434, DDE (Dichlorodiphenyldichloroethylene)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127798

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The DDE(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRPDDM, 715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104434, DDE (Dichlorodiphenyldichloroethylene)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29497

Pollutant:

o,p'-DDD (Dichlorodiphenyldichloroethane)) | o,p'-DDE (Dichlorodiphenyldichloroethylene) | o,p'-DDT (Dichlorodiphenyltrichloroethane) | p,p'-DDMU

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of o,p'-DDD, o,p'-DDE, o,p'-DDT, or p,p'-DDMU for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104434, DDE (Dichlorodiphenyldichloroethylene)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34548

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The method detection limit for all 6 of the non-detect samples was greater than the criteria: thus the data was not used in this assessment.

Data Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 4,4'-DDE criterion for the protection of human health from the consumption of water and organisms is 0.00022 ug/L (USEPA Nationally Recommended Criteria, 2006).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at stations 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104434, DDE (Dichlorodiphenyldichloroethylene)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127797

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The DDE(4,4') criteria for the protection of human health from consumption of organisms only is 0.00059 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRPDDM, 715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104434, DDE (Dichlorodiphenyldichloroethylene)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32932

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 4 samples collected for Sum DDE exceeded the evaluation guideline.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Probable Effect Concentration for Sum DDE (o,p' + p,p') in freshwater sediments is 31.3 ug/kg.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following station: Colorado River at Imperial Dam Grates - 715CRIDG1.

Temporal Representation:

The samples were collected on 10/25/2005 - 4/21/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 104434, DDE (Dichlorodiphenyldichloroethylene)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125494

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104434, DDE (Dichlorodiphenyldichloroethylene)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125493

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104418	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Dacthal
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Seven lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Fifteen dissolved fraction water samples and fifteen sediment samples were generally collected from 5/2002 through 5/2004; however, no evaluation guidelines for the sediment for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. None of six water samples exceeded the National Recommended Water Quality Criteria for dacthal (DCPA) for the consumption of water and fish of 0.008 ug/L. None of four water samples exceeded the USEPA drinking water health advisory for lifetime exposure to DCPA is 0.007 mg/L. The sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104418, Dacthal	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127377

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Dacthal is the USEPA Aquatic Life Benchmark of > 11000 ug/L for a nonvascular plant (acute) and vascular plant (acute). The benchmark was derived from a 'greater-than' value (for example, > 265,000) and may overestimate toxicity.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104418, Dacthal	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35005

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50 for Dacthal 6600 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104418, Dacthal	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29574

Pollutant:

Dacthal | Mirex | Oxadiazon

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Dacthal, Mirex, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104418, Dacthal	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29809

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104418, Dacthal	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128613

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104418, Dacthal	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127376

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA drinking water health advisory for lifetime exposure to DCPA is 0.007 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104418, Dacthal	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35343

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The National Recommended Water Quality Criteria for dacthal (DCPA) for the consumption of water and fish is 0.008 ug/L.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	78225	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Deltamethrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Six lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 13 sediment samples exceeded the median lethal concentration (LC50). None of six dissolved fraction water samples exceeded the maximum acceptable toxicant concentration (MATC). None of six total fraction water samples exceeded the USEPA Aquatic Life Benchmark. These sample size are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78225, Deltamethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46335

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for deltamethrin is the maximum acceptable toxicant concentration (MATC) of 0.02 ug/L, which is the geometric mean of the LOEC and NOEC, as determined in a 280 day toxicity study with the fathead minnow, Pimephales promelas. (USEPA OPP Ecotoxicity database)

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78225, Deltamethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127501

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Deltamethrin/Tralomethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78225, Deltamethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127500

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Deltamethrin/Tralomethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78225, Deltamethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35488

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78225, Deltamethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125433

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data were collected from 4 (Station Codes: 715CRSQLK, 715CRPDDM, 715CRIDU1, 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78225, Deltamethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125432

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data were collected from 4 (Station Codes: 715CRSQLK, 715CRPDDM, 715CRIDU1, 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104411	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Demeton
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29809 received a use rating of insufficient in a previous assessment cycle because no evaluation guideline was available for this pollutant. None of the samples exceeded the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of three water samples exceeded the National Recommended Water Quality Criteria Continuous Concentrations (4-day average concentrations) for freshwater aquatic organisms None of 15 dissolved fraction water samples collected years 2002-2004 exceeded the guideline as no evaluation guidelines for the dissolved fractions for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. The sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104411, Demeton	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127617

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentrations (4-day average concentrations) for freshwater aquatic organisms exposure to Demeton is 0.1 ug/L.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104411, Demeton	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29809

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104411, Demeton	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127511

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentrations (4-day average concentrations) for freshwater aquatic organisms exposure to Demeton is 0.1 ug/L.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104411, Demeton	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127512

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA expected safe lifetime exposure limit in drinking water for Demeton, calculated using the IRIS Reference Dose, is 0.3 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.00004 mg/kg/day as the reference dose.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	70623	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Diazinon
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1, 3.5 and 3.6 of the Listing Policy. Under sections 3.1 and 3.5 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Nine lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of seven sediment samples exceeded the sediment quality guideline. None of 17 dissolved fraction water samples exceeded the California Department of Fish and Games (CDFG) Hazardous Assessment Criteria. None of 11 total fraction water samples exceeded the freshwater chronic value expressed as a continuous concentration. None of one tissue samples exceeded the modified OEHHA Fish Contaminant Goal. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70623, Diazinon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45952

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for diazinon in fish tissue is 1,500 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70623, Diazinon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125770

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70623, Diazinon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35492

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70623, Diazinon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7690

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Fish and Games (CDFG) Hazardous Assessment Criteria of 0.16 ug/l for the protection of aquatic life uses (Siepmann and Finlayson, 2000).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70623, Diazinon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125497

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70623, Diazinon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127141

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70623, Diazinon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127140

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA drinking water health advisory for diazinon is 1.4 µg/L.

Guideline Reference:

2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70623, Diazinon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127142

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70623, Diazinon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35212

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	70444	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Dibenz[a,h]anthracene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 11 dissolved fraction and none of six total fraction water samples exceeded the California Toxics Rule criteria. The sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 70444, Dibenz[a,h]anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127153

Pollutant:

Dibenz[a,h]anthracene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dibenzo(a, h)anthracene criteria for the protection of human health from consumption of organisms only is 0.049 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70444, Dibenz[a,h]anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127536

Pollutant:

Dibenz[a,h]anthracene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dibenz(a,h)anthracene. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dibenzo(a, h)anthracene criteria for the protection of human health from the consumption of water and organisms is 0.0044 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-05-10 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70444, Dibenz[a,h]anthracene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7662

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	78487	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Dichlorvos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceeded the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of six total fraction water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database aquatic life MATC. Zero of zero dissolved fraction water samples exceeded the USEPA Aquatic Life Benchmark. Three samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. The sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78487, Dichlorvos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127061

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78487, Dichlorvos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35258

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life MATC for Dichlorvos is 7.2 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78487, Dichlorvos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128913

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	104432	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Dicrotophos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of three total fraction samples exceeded the USEPA expected safe lifetime exposure limit in drinking water. Zero of 15 dissolved fraction water samples collected 2002-2004 exceeded the guideline as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104432, Dicrotophos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127772

Pollutant:

Dicrotophos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA expected safe lifetime exposure limit in drinking water for Dicrotophos calculated using the IRIS Reference Dose, is 0.7 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.0001 mg/kg/day as the reference dose.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104432, Dicrotophos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29496

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos, Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70025	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Dieldrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1, 3.5 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List Twenty lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction water samples exceeded the CTR criterion maximum concentration (CMC). None of 10 total fraction water samples exceeded the CTR criterion continuous concentration (CCC). None of 24 sediment samples exceeded the sediment quality guideline. None of seven fish tissue sample exceeded the NAS fish tissue evaluation guideline. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126340

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Dieldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126537

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127162

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35325

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35303

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dieldrin criteria for the protection of human health from the consumption of water and organisms is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127059

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dieldrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dieldrin criteria for the protection of human health from the consumption of water and organisms is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127044

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dieldrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dieldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35282

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dieldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7634

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45953

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Dieldrin. One composite (6 fish per composite) were generated from one species: largemouth bass. One sample was not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for dieldrin in fish tissue is 0.32 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126538

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Dieldrin. Although data was collected for 4 fish species (1 composite(s) of Channel Catfish each composed of 2 fish per composite, 1 composite(s) of Common Carp each composed of 5 fish per composite, 1 composite(s) of Flathead Catfish each composed of 5 fish per composite, 1 composite(s) of Striped Bass each composed of 5 fish per composite), all 4 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126341

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP Sportfish Rivers and Streams data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Dieldrin. Although data was collected for 1 fish species (1 composite(s) of Common Carp each composed of 5 fish per composite), all 1 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126426

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45954

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126415

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125417

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125890

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35326

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70025, Dieldrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127161

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	103763	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Dimethoate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceeded the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the samples exceeded the water quality objective(s). Sample sizes were less than 16 for each beneficial use/matrix/fraction/objective combination. The sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103763, Dimethoate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29809

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 103763, Dimethoate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128133

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103763, Dimethoate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128134

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103763, Dimethoate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35010

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50 for Dimethoate is 43 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):


DECISION ID	103767	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Disulfoton
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceeded the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the samples exceeded the water quality objective(s). Sample sizes were less than 16 for each beneficial use/matrix/fraction/objective combination. The sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103767, Disulfoton	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128894

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Disulfoton. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Disulfoton is the USEPA Aquatic Life Benchmark of 0.01 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103767, Disulfoton	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29809

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 103767, Disulfoton	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128892

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Disulfoton. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Disulfoton is the USEPA Aquatic Life Benchmark of 0.01 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	78227	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Endosulfan
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 and 3.5 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Yen lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of seven tissue samples exceeded the National Academy of Science guidelines, and none of six water samples exceeded the USEPA National Recommended Water Quality Criteria. These sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78227, Endosulfan	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126429

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Endosulfan, Total concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78227, Endosulfan	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45963

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endosulfan, Total. One composite (6 fish per composite) were generated from one species: Largemouth Bass. Total endosulfan was calculated as the sum of endosulfan l and endosulfan ll.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total Endosulfan concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78227, Endosulfan	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126530

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78227, Endosulfan	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126336

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for endosulfan (l and ll) in fish tissue is 13,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; USEPA, 2000)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78227, Endosulfan	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126427

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78227, Endosulfan	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45955

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endosulfan, Total. One composite (6 fish per composite) were generated from one species: Largemouth Bass. Total endosulfan was calculated as the sum of endosulfan l and endosulfan ll.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78227, Endosulfan	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126529

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78227, Endosulfan	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33090

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples exceeded the criteria.

Data Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The endosulfan criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L. This value corresponds to the sum of alpha-endosulfan and beta-endosulfan (USEPA National Recommended Water Quality Criteria, 2006).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples were collected on 10/25/2005, 5/3/2006, 5/8/2007, 10/23/2007, 4/22/2008, and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78227, Endosulfan	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127804

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan criterion (for the total concentrations of alpha-endosulfan [Endosulfan I] and beta-endosulfan [Endosulfan II]) for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78227, Endosulfan	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126531

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70085	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Endrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1, 3.5 and 3.6 of the Listing Policy. Under sections 3.1 and 3.5 of the Policy, one line of evidence is needed to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity. Twenty-four lines of evidence are available in the administrative record to assess this pollutant. LOE No. 7674 is replaced by the LOE No. 7652 and LOE No. 27211 is replaced by the LOE No. 46763 because it was re-assessed with a different guideline. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 24 sediment samples exceeded the sediment quality guideline. None of seven fish tissue sample exceeded the National Academy of Science guidelines for protection of aquatic life from bioaccumulation of toxic substances. None of 17 dissolved fraction and none of 10 total fraction water samples exceeded the California Toxics Rule criteria protecting human health when consuming water and organisms from these waters. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126339

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Endrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126338

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for endrin in fish tissue is 660 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; USEPA, 2000)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126603

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45964

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45965

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126602

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126422

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125566

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Endrin from MacDonald et al., 2000a which states that the probable effect concentration for Endrin is 207 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125508

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Endrin from MacDonald et al., 2000a which states that the probable effect concentration for Endrin is 207 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35073

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127183

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127187

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin criteria for the protection of human health from consumption of organisms only is 0.81 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35061

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin criteria for the protection of human health from consumption of organisms only is 0.81ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127184

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin criteria for the protection of human health from the consumption of water and organisms is 0.76 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35066

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin criteria for the protection of human health from the consumption of water and organisms is 0.76 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35072

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127185

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7634

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70085, Endrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126604

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	71331	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Endrin aldehyde
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27211 is replaced by the LOE No. 46763. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction water samples exceeded the California Toxics Rule criteria protecting human health when consuming water and organisms from these waters. None of ten total fraction water samples exceeded the California Toxics Rule criteria protecting human health when consuming organisms only from these waters. None of four total fraction water samples exceeded the California Toxics Rule criteria protecting human health when consuming water and organisms from these waters. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 71331, Endrin aldehyde	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71331, Endrin aldehyde	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71331, Endrin aldehyde	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128150

Pollutant:

Endrin aldehyde

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin Aldehyde criteria for the protection of human health from consumption of water and organisms is 0.76 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71331, Endrin aldehyde	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35084

Pollutant:

Endrin aldehyde

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin Aldehyde criteria for the protection of human health from consumption of organisms only is 0.81ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71331, Endrin aldehyde	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128149

Pollutant:

Endrin aldehyde

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin Aldehyde criteria for the protection of human health from consumption of organisms only is 0.81ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71331, Endrin aldehyde	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	78802	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Esfenvalerate/Fenvalerate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List Six lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of eight sediment samples exceeded the median lethal concentration (LC50). None of ten water samples exceeded the USEPA Aquatic Life Benchmark. These sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78802, Esfenvalerate/Fenvalerate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127751

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Esfenvalerate/Fenvalerate, Total is the USEPA Aquatic Life Benchmark of 0.017 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78802, Esfenvalerate/Fenvalerate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127749

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Esfenvalerate/Fenvalerate, Total is the USEPA Aquatic Life Benchmark of 0.017 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78802, Esfenvalerate/Fenvalerate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46357

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.13 ug/L, as determined in a 96 hour toxicity test using the fathead minnow, Pimephales promelas. (USEPA OPP Ecotoxicity database)

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78802, Esfenvalerate/Fenvalerate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125746

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78802, Esfenvalerate/Fenvalerate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125732

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78802, Esfenvalerate/Fenvalerate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35435

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	103768	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Ethion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the samples exceed the water quality objective: Zero of 15 dissolved fraction water samples exceed the water quality objective as no evaluation guidelines for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. Zero of the five total fraction samples exceed the USEPA expected safe lifetime exposure limit in drinking water. Zero of the zero total fraction water samples exceed the USEPA national ambient water quality criterion for freshwater aquatic life. Five samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Sample sizes for each beneficial use/matrix/fraction/objective sample set was less than 16. These sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103768, Ethion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29493

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 103768, Ethion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128723

Pollutant:

Ethion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA expected safe lifetime exposure limit in drinking water for Ethion, calculated using the IRIS Reference Dose, is 3.5 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.0005 mg/kg/day as the reference dose.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103768, Ethion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127014

Pollutant:

Ethion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ethion. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA national ambient water quality criterion for freshwater aquatic life instantaneous maximum for ethion is 0.02 µg/L. (National Aquatic Life Criteria 1972. Page 186 Table III-18)

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 103768, Ethion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127567

Pollutant:

Ethion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ethion. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA national ambient water quality criterion for freshwater aquatic life instantaneous maximum for ethion is 0.02 µg/L. (National Aquatic Life Criteria 1972. Page 186 Table III-18)

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	103778	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Ethoprop
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 dissolved fraction water samples and zero of five total fraction water samples exceeded the objective(s). These sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103778, Ethoprop	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29809

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 103778, Ethoprop	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128731

Pollutant:

Ethoprop

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103778, Ethoprop	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128732

Pollutant:

Ethoprop

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	71484	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Ethylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. LOE No. 7652 is replaced by the LOE No. 7674 and not included in the final use rating. None of other samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the California Toxics Rule criteria protecting human health when consuming water and organisms from these waters. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71484, Ethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126869

Pollutant:

Ethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Ethylbenzene is 0.3 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71484, Ethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35120

Pollutant:

Ethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Ethylbenzene is 300 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71484, Ethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71484, Ethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71484, Ethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71484, Ethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35116

Pollutant:

Ethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Ethylbenzene criteria for the protection of human health from consumption of organisms only is 29,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71484, Ethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126870

Pollutant:

Ethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Ethylbenzene criteria for the protection of human health from consumption of organisms only is 29,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71484, Ethylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	103783	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Fenitrothion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 dissolved fraction water samples exceeded the objective as no evaluation guidelines for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. Zero of five total fraction water samples exceeded the USEPA Aquatic Life Benchmark. These sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103783, Fenitrothion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127831

Pollutant:

Fenitrothion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Fenitrothion is the USEPA Aquatic Life Benchmark of 0.087 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103783, Fenitrothion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29493

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 103783, Fenitrothion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127832

Pollutant:

Fenitrothion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Fenitrothion is the USEPA Aquatic Life Benchmark of 0.087 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	78124	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Fenpropathrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Six lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceeded the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of three water samples exceeded the evaluation guideline of median lethal concentration (LC50), and none of four water samples exceeded the USEPA Aquatic Life Benchmark. None of five sediment samples exceeded the evaluation guideline of median lethal concentration (LC50). These sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78124, Fenpropathrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125686

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78124, Fenpropathrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125446

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78124, Fenpropathrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46448

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for fenpropathrin, 2.2 ug/L, is the median lethal concentration (LC50) as determined in a 96 hour toxicity test using the bluegill sunfish, Lepomis macrochirus. (USEPA OPP Ecotoxicity database)

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/23/2007-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78124, Fenpropathrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127378

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.064 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 78124, Fenpropathrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35463

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/23/2007-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78124, Fenpropathrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127473

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.064 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	103794	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Fenthion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceeded the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 dissolved fraction as no evaluation guidelines for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. Zero of zero total fraction water samples exceeded the USEPA Aquatic Life Benchmark. Three samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. The sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103794, Fenthion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127056

Pollutant:

Fenthion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenthion. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Fenthion is the USEPA Aquatic Life Benchmark of 0.013 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103794, Fenthion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29493

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 103794, Fenthion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128964

Pollutant:

Fenthion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenthion. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Fenthion is the USEPA Aquatic Life Benchmark of 0.013 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	71217	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Fluoranthene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Nine lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27211 is replaced by the LOE No. 46763. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 25 total fraction and zero of one "not recorded" fraction sediment samples exceeded the Consensus Based Sediment Quality Guideline Probable Effects Concentrations (PECs) for the protection of freshwater organisms to toxic effects. Zero of 17 dissolved fraction and zero of six total fraction water samples exceeded the California Toxics Rule (CTR) Criteria for the protection of human health when consuming organisms from aquatic systems. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71217, Fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128255

Pollutant:

Fluoranthene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Fluoranthene criteria for the protection of human health from the consumption of water and organisms is 300 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71217, Fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127484

Pollutant:

Fluoranthene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Fluoranthene criteria for the protection of human health from consumption of organisms only is 370 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71217, Fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125899

Pollutant:

Fluoranthene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Fluoranthene from MacDonald et al., 2000a which states that the probable effect concentration for Fluoranthene is 2230 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71217, Fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35511

Pollutant:

Fluoranthene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for fluoranthene is 2230 ug/kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71217, Fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125617

Pollutant:

Fluoranthene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Fluoranthene from MacDonald et al., 2000a which states that the probable effect concentration for Fluoranthene is 2230 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71217, Fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71217, Fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71217, Fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71217, Fluoranthene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	71218	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Fluorene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Eight lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27211 is replaced by the LOE No. 46763. None of other samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the California Toxics Rule criteria protecting human health when consuming water and organisms from these waters. None of 24 sediment samples exceeded the Probable Effects Concentrations (PECs). These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71218, Fluorene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125576

Pollutant:

Fluorene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Fluorene from MacDonald et al., 2000a which states that the probable effect concentration for Fluorene is 536 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71218, Fluorene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32984

Pollutant:

Fluorene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 4 samples collected for fluorene (Sum of c0-c3) exceeded the evaluation guideline.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Probable Effect Concentration for fluorene in freshwater sediments is 536 ug/kg.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following station: Colorado River at Imperial Dam Grates - 715CRIDG1.

Temporal Representation:

The samples were collected on 10/25/2005 - 4/21/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71218, Fluorene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127785

Pollutant:

Fluorene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Fluorene criteria for the protection of human health from the consumption of water and organisms is 1,300 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71218, Fluorene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125841

Pollutant:

Fluorene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Fluorene from MacDonald et al., 2000a which states that the probable effect concentration for Fluorene is 536 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71218, Fluorene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71218, Fluorene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71218, Fluorene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71218, Fluorene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104412	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Fluoride
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. T wo lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 39 samples exceeded the Water Quality for Agriculture (published by the Food and Agriculture Organization of the United Nations in 1985), criteria protective of various agricultural uses of irrigation water. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 104412, Fluoride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126100

Pollutant:

Fluoride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 39 samples exceeded the water quality standard for Fluoride.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Primary Maximum Contaminant Level (MCL) for Fluoride, is 2 mg/l.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2017-03-10

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 104412, Fluoride	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126008

Pollutant:

Fluoride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 39 samples exceeded the water quality standard for Fluoride.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. A 1 mg/L criteria is the recommended maximum concentration of Fluoride in irrigation water.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2017-03-10

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.


DECISION ID	70959	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Heptachlor
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 and 3.5 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Fourteen lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction water samples exceeded either the California Toxics Rule Criterion Maximum Concentration (CMC) criteria. None of ten total fraction water samples exceeded either the California Toxics Rule Criterion Continuous Concentration (CCC) criteria. None of seven fish tissue sample exceeded the NAS fish tissue evaluation guideline. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35160

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor criteria for the protection of human health from consumption of organisms only is 0.00021 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128520

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor criteria for the protection of human health from consumption of organisms only is 0.00021 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128056

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126573

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Heptachlor concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126166

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35093

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor criteria for the protection of human health from the consumption of water and organisms is 0.00021 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45975

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126571

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126587

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128057

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35109

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127026

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor criteria for the protection of human health from the consumption of water and organisms is 0.00021 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70959, Heptachlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7634

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70747	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Heptachlor epoxide
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 and 3.5 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Seventeen lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and zero of ten total fraction water samples exceeded either the California Toxics Rule criteria. Zero of seven fish tissue sample exceeded the OEHHA fish contaminant goal. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35128

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criteria for the protection of human health from consumption of organisms only is 0.00011 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126471

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Heptachlor Epoxide concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35145

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criteria for the protection of human health from the consumption of water and organisms is 0.00010 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126889

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35149

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127222

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criteria for the protection of human health from the consumption of water and organisms is 0.00010 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45977

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126434

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126433

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126241

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126470

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Heptachlor Epoxide. Although data was collected for 4 fish species (1 composite(s) of Channel Catfish each composed of 2 fish per composite, 1 composite(s) of Common Carp each composed of 5 fish per composite, 1 composite(s) of Flathead Catfish each composed of 5 fish per composite, 1 composite(s) of Striped Bass each composed of 5 fish per composite), all 4 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for heptachlor epoxide in fish tissue is 0.93 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; OEHHA, 1999)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Public Health Goal for Heptachlor and Heptachlor Epoxide in Drinking Water

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7634

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126576

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP Sportfish Rivers and Streams data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Heptachlor Epoxide. Although data was collected for 1 fish species (1 composite(s) of Common Carp each composed of 5 fish per composite), all 1 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Public Health Goal for Heptachlor and Heptachlor Epoxide in Drinking Water

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45976

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor epoxide. One composite (6 fish per composite) were generated from one species: largemouth bass. One sample was not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Public Health Goal for Heptachlor and Heptachlor Epoxide in Drinking Water

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127221

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criteria for the protection of human health from consumption of organisms only is 0.00011 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126891

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70747, Heptachlor epoxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70567	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Hexachlorobenzene/ HCB
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 and 3.5 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction water samples exceeded the drinking water MCL. Ten total fraction water samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. None of seven fish tissue sample exceeded the OEHHA fish contaminant goal. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70567, Hexachlorobenzene/ HCB	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128439

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Hexachlorobenzene. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Hexachlorobenzene criteria for the protection of human health from the consumption of water and organisms is 0.00075 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70567, Hexachlorobenzene/ HCB	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35524

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Hexachlorobenzene criteria for the protection of human health from the consumption of water and organisms is 0.00075 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70567, Hexachlorobenzene/ HCB	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126425

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for hexachlorobenzene in fish tissue is 2.8 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; OEHHA, 2005)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70567, Hexachlorobenzene/ HCB	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45986

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70567, Hexachlorobenzene/ HCB	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70567, Hexachlorobenzene/ HCB	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126459

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70567, Hexachlorobenzene/ HCB	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128438

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Hexachlorobenzene. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Hexachlorobenzene criteria for the protection of human health from consumption of organisms only is 0.00077 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70567, Hexachlorobenzene/ HCB	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35520

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Hexachlorobenzene criteria for the protection of human health from consumption of organisms only is 0.00077 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	71646	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Hexachlorobutadiene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27212 is replaced by the LOE No. 46762 because it was re-assessed using a different objective. None of other samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction water samples exceeded the California Toxics Rule criteria for the protection of human health when consuming organisms only from aquatic systems. None of 11 dissolved fraction water samples exceeded the California Toxics Rule criteria for the protection of human health when consuming water and organisms from aquatic systems. Six samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. None of six total fraction water samples exceeded the California Toxics Rule criteria for the protection of human health when consuming organisms only from aquatic systems. None of two total fraction water samples exceeded the California Toxics Rule criteria for the protection of human health when consuming water and organisms from aquatic systems. Four samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71646, Hexachlorobutadiene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128245

Pollutant:

Hexachlorobutadiene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Hexachlorobutadiene criteria for the protection of human health from consumption of organisms only is 50 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71646, Hexachlorobutadiene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46761

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen samples were taken at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71646, Hexachlorobutadiene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7649

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71646, Hexachlorobutadiene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27212

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71646, Hexachlorobutadiene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35566

Pollutant:

Hexachlorobutadiene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Hexachlorobutadiene criteria for the protection of human health from the consumption of water and organisms is 0.44 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71646, Hexachlorobutadiene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128499

Pollutant:

Hexachlorobutadiene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Hexachlorobutadiene. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Hexachlorobutadiene criteria for the protection of human health from the consumption of water and organisms is 0.44 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71646, Hexachlorobutadiene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35546

Pollutant:

Hexachlorobutadiene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Hexachlorobutadiene criteria for the protection of human health from consumption of organisms only is 50 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70143	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Indeno[1,2,3-cd]pyrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 11 dissolved fraction and none of 6 total fraction water samples exceeded the California Toxics Rule criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 70143, Indeno[1,2,3-cd]pyrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7662

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70143, Indeno[1,2,3-cd]pyrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128254

Pollutant:

Indeno[1,2,3-cd]pyrene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Indeno(1, 2, 3-C, D)Pyrene criteria for the protection of human health from consumption of organisms only is 0.049 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70143, Indeno[1,2,3-cd]pyrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128503

Pollutant:

Indeno[1,2,3-cd]pyrene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Indeno(1,2,3-c,d)pyrene. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Indeno(1, 2, 3-C, D)Pyrene criteria for the protection of human health from the consumption of water and organisms is 0.0044 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-05-10 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70955	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Indicator Bacteria
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.21 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Two of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Two of 16 water samples exceeded the Basin Plan objective for Enterococcus for water contact recreation. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 26 samples is needed for application of table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 70955, Indicator Bacteria	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33245

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

The one sample collected did not exceed the E. coli objective.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The E. coli concentration shall not exceed more than 235/100ml. Basin Plan for the Colorado River Basin.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The sample was collected from the Colorado River at Imperial Dam Grates station 715CRIDG1.

Temporal Representation:

The sample was collected in October 2005.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70955, Indicator Bacteria	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126139

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 38 samples exceeded the Statistical Threshold Value (STV) water quality standard for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a STATISTICAL THRESHOLD VALUE (STV) of 320 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s), station(s): USGS-09427520, USGS-09429490

Temporal Representation:

The samples were collected between the days of 2010-11-23 and 2016-06-22 .

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70955, Indicator Bacteria	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7704

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan:In the Colorado River the maximum allowable E. coli density is 1175 MPN/ 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Fifteen water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 10/2004 from the Imperial Dam grate locations. Samples were usually collected in May and October. The rest of the locations were sampled in May and October 2002. An extra sample was collected from the upstream of Imperial Dam location in April 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70955, Indicator Bacteria	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7701

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan:In the Colorado River the maximum allowable E. coli density is 235 MPN/ 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70955, Indicator Bacteria	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7609

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, 2 exceeded the Basin Plan Objective (SWAMP, 2007). The exceedance were found in samples collected on 10/02/2002 at Taylor Lake, and 11/04/2003 at the Imperial Dam grates (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan:In the Colorado River the maximum allowable Enterococcus density is 61 MPN/ 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 70955, Indicator Bacteria	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7612

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, 2 exceeded the Basin Plan Objective. The exceedance were found in samples collected on 10/02/2002 at Taylor Lake, and 11/04/2003 at the Imperial Dam grates (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan:In the Colorado River the maximum allowable Enterococcus density is 305 MPN/ 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70955, Indicator Bacteria	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33246

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

The one sample collected did not exceed the entercoccus objective.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The entercoccus concentration shall not exceed more than 61/100ml. Basin Plan for the Colorado River Basin.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The sample was collected from the Colorado River at Imperial Dam Grates station 715CRIDG1.

Temporal Representation:

The samples were collected in October 2005.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70955, Indicator Bacteria	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126142

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the Statistical Threshold Value (STV) water quality standard for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s), station(s): 715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK

Temporal Representation:

The samples were collected between the days of 2013-04-15 and 2013-04-17 .

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104429	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Iron
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of one sample exceeded the California Secondary MCL. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104429, Iron	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126073

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Iron.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for iron is 0.3 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2017-03-10 and 2017-03-10

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.


DECISION ID	103851	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Jasmolin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the eight samples exceed the USEPA Aquatic Life Benchmark for Jasmolin-1 and Jasmolin-2. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the eight samples exceed the USEPA Aquatic Life Benchmark for Jasmolin-1 and Jasmolin-2. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103851, Jasmolin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128845

Pollutant:

Jasmolin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Jasmolin-1 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103851, Jasmolin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127165

Pollutant:

Jasmolin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Jasmolin-2 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103851, Jasmolin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128846

Pollutant:

Jasmolin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Jasmolin-1 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103851, Jasmolin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128090

Pollutant:

Jasmolin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Jasmolin-2 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	70079	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Lead
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Thirteen lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction water samples exceeded the California Toxics Rule criterion maximum concentration. None of 50 dissolved fraction water samples exceeded the California Toxics Rule criterion continuous concentration. None of eight sediment samples exceeded the sediment quality guideline line. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127522

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126098

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 34 samples exceeded the water quality standard for Lead.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125924

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality standard for Lead.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for lead in the Basin Plan is 0.015 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2013-11-21

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126900

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for lead in the Basin Plan is 0.015 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126899

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126044

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 34 samples exceeded the water quality standard for Lead.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125893

Pollutant:

Lead

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Lead from MacDonald et al., 2000a which states that the probable effect concentration for Lead is 128 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7637

Pollutant:

Lead | Nickel | Silver | Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule Hardness Dependent Criterion Maximum Concentrations (CMCs) for the protection of freshwater aquatic life uses were used for the following constituents: Lead,Nickel, Silver, and Zinc (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32919

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples exceeded the hardness based criteria calculated for lead.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at stations 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126089

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality standard for Lead.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for lead in the Basin Plan is 0.015 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125894

Pollutant:

Lead

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Lead from MacDonald et al., 2000a which states that the probable effect concentration for Lead is 128 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35569

Pollutant:

Lead

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70079, Lead	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7693

Pollutant:

Cadmium | Lead | Lindane/gamma Hexachlorocyclohexane (gamma-HCH) | Methoxychlor | Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	71384	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1, 3.5 and 3.6 of the Listing Policy. Under sections 3.1 and 3.5 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Twenty-one lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 21 sediment samples exceeded the sediment quality guideline. None of 10 total fraction water samples exceeded the CTR criteria. None of 17 dissolved fraction water samples exceeded the MCL or Basin Plan objective. None of seven fish tissue sample exceeded the OEHHA fish contaminant goal or NAS guidelines. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35125

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Lindane (gamma-HCH) is 4.99 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127646

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The gamma-BHC (Lindane) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/L. Footnote g specifies that (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35088

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The HCH, Gamma (Lindane) criterion for the protection of human health from the consumption of organisms is 0.063 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127649

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The BHC, gamma criteria for the protection of human health from consumption of organisms only is 0.063 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127618

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The BHC, gamma(Lindane) criteria for the protection of human health from the consumption of water and organisms is 0.019 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35105

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The BHC, gamma(Lindane) criteria for the protection of human health from the consumption of water and organisms is 0.019 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35124

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The gamma-BHC (Lindane) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125802

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Lindane from MacDonald et al., 2000a which states that the probable effect concentration for Lindane is 4.99 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125601

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Lindane from MacDonald et al., 2000a which states that the probable effect concentration for Lindane is 4.99 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126334

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Lindane concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45974

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126640

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45966

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for lindane in fish tissue is 4.6 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126578

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126441

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126331

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127648

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The gamma-BHC (Lindane) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7693

Pollutant:

Cadmium | Lead | Lindane/gamma Hexachlorocyclohexane (gamma-HCH) | Methoxychlor | Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71384, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126641

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	103906	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Malathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the samples exceeded the objectives: Zero of 15 dissoved fraction water samples (collected 2002-2004) exceeded the objective as no evaluation guidelines for the dissolved fraction could be found that met the requirements of Section 6.1.3 of the Listing Policy. Zero of zero total fraction water samples (collected 2005-2013) exceeded the UC Davis Criteria for Malathion for the protection of aquatic organisms. Eleven samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103906, Malathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35608

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The UC Davis Criteria for Malathion for the protection of aquatic organisms is a 4 day average of 0.028 ug/L.

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 103906, Malathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128456

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The UC Davis Criteria for Malathion for the protection of aquatic organisms is a 4 day average of 0.028 ug/L.

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 103906, Malathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29493

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 103906, Malathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128944

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The UC Davis Criteria for Malathion for the protection of aquatic organisms is a 4 day average of 0.028 ug/L.

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	71380	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Manganese
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. One of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of 38 total fraction water samples exceeded the drinking water secondary MCL. None of 34 dissolved fraction water samples exceeded the drinking water secondary MCL. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71380, Manganese	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35629

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The California Secondary MCL for manganese is 0.05 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR title 22 section 64449.

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71380, Manganese	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128636

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for manganese is 0.5 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71380, Manganese	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126010

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Manganese.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for manganese is 0.5 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2017-03-10 and 2017-03-10

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71380, Manganese	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7679

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71380, Manganese	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126079

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 1 of 38 samples exceeded the water quality standard for Manganese.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for manganese is 0.5 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.


DECISION ID	71477	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Mercury
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1, 3.5 and 3.6 of the Listing Policy. Under sections 3.1 and 3.5 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Thirty-four lines of evidence are available in the administrative record to assess this pollutant. LOE No. 7674 is replaced by the LOE No. 7652 because it is assessed using a different guideline. LOE No. 45987 was assessed using a different guideline. None of other samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 31 dissolved and none of one total fraction water samples exceeded the California Toxics Rule criteria for the protection of human health from the consumption of water and organisms. None of 25 sediment samples exceeded the sediment quality guideline. None of three fish tissue sample exceeded the Statewide Sport Fish Water Quality Objective for the protection of the Commercial and Sport Fishing. None of three fish tissue sample exceeded the Statewide Sport Fish Water Quality Objective for the protection of Wildlife Habitat . These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

132857

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 12 fish were aggregated into 1 annual averages, which consisted of 2 fish species (1 composite(s) of Largemouth Bass each composed of 6 fish per composite, 6 composite(s) of Largemouth Bass each composed of 1 fish per composite).

Data Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Statewide Sport Fish Water Quality Objective for the protection of the Commercial and Sport Fishing beneficial comes from the Statewide Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, and is 0.2 mg/Kg wet weight skinless fillet samples of trophic level 3, or trophic level 4 fish (whichever is highest in the water body) over a one year averaging period. Trophic levels of applicable fish are defined in, but not limited to those in Attachment C of the Final Regulatory Language document (Appendix A) of State Water Resources Control Board Resolution No. 2017-0027.

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRIDG1.

Temporal Representation:

Data for this line of evidence were collected between 2004-12-07 and 2004-12-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45987

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Mercury. Seven composites were generated from one species: largemouth bass. Composites comprised of 1 fish per composite. Composites collected at the same time on the same day for the same species were averaged in accordance with the listing policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The USEPA 304(a) recommended water quality criterion for concentrations of methylmercury in fish tissue of trophic level 4 fish (150 - 500 mm; fillet wet weight) is 0.20 mg/kg.

Guideline Reference:

Water Quality Criterion for the Protection of Human Health: Methylmercury. Final. United States Environmental Protection Agency Office of Science and Technology Office of Water. EPA-823-R-01-001. January 2001

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

132825

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Sportfish Rivers and Streams data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 11 fish were aggregated into 1 annual averages, which consisted of 1 fish species (11 composite(s) of Largemouth Bass each composed of 1 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

133119

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 22 fish were aggregated into 1 annual averages, which consisted of 3 fish species (1 composite(s) of Channel Catfish each composed of 2 fish per composite, 11 composite(s) of Largemouth Bass each composed of 1 fish per composite, 9 composite(s) of Striped Bass each composed of 1 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-22 and 2014-11-04

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

132891

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 3 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 10 fish were aggregated into 1 annual averages, which consisted of 2 fish species (1 composite(s) of Bluegill each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 5 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-28 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

133034

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 3 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 10 fish were aggregated into 1 annual averages, which consisted of 2 fish species (1 composite(s) of Bluegill each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 5 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-28 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

133342

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 12 fish were aggregated into 1 annual averages, which consisted of 3 fish species (1 composite(s) of Channel Catfish each composed of 2 fish per composite, 8 composite(s) of Largemouth Bass each composed of 1 fish per composite, 2 composite(s) of Striped Bass each composed of 1 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-22 and 2014-11-04

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

133143

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Sportfish Rivers and Streams data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 7 fish were aggregated into 1 annual averages, which consisted of 1 fish species (7 composite(s) of Largemouth Bass each composed of 1 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The Statewide Sport Fish Water Quality Objective for the protection of Wildlife Habitat comes from the Statewide Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, and is 0.2 mg/Kg wet weight skinless fillet samples of trophic level 3, or trophic level 4 fish (whichever is highest in the water body) over a one year averaging period. If trophic level 3 fish are used in the assessment then the Prey Fish Water Quality Objective must also be used to determine that the Sport Fish Objective is being met. Trophic levels of applicable fish are defined in, but not limited to those in Attachment C of the Final Regulatory Language document (Appendix A) of State Water Resources Control Board Resolution No. 2017-0027.

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

133132

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 22 fish were aggregated into 1 annual averages, which consisted of 3 fish species (1 composite(s) of Channel Catfish each composed of 2 fish per composite, 11 composite(s) of Largemouth Bass each composed of 1 fish per composite, 9 composite(s) of Striped Bass each composed of 1 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-22 and 2014-11-04

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

133083

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

133067

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 12 fish were aggregated into 1 annual averages, which consisted of 2 fish species (6 composite(s) of Largemouth Bass each composed of 1 fish per composite, 1 composite(s) of Largemouth Bass each composed of 6 fish per composite).

Data Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRIDG1.

Temporal Representation:

Data for this line of evidence were collected between 2004-12-07 and 2004-12-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125437

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Mercury from MacDonald et al., 2000a which states that the probable effect concentration for Mercury is 1.06 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35675

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for mercury is 1.06 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125834

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Mercury from MacDonald et al., 2000a which states that the probable effect concentration for Mercury is 1.06 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125981

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Mercury.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Mercury criteria for the protection of human health from consumption of organisms only is 0.051 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-09427520)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2011-02-15

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126128

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Mercury.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-09427520)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2011-02-15

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35651

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Mercury criteria for the protection of human health from consumption of organisms only is 0.051 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127637

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Mercury criteria for the protection of human health from consumption of organisms only is 0.051 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126071

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Mercury.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Mercury criteria for the protection of human health from consumption of organisms only is 0.051 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-09427520)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2011-02-15

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127639

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126031

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Mercury.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-09427520)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2011-02-15

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35655

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7640

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen water samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the NRWQC criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

National Recommended Water Quality Criteria (NRWQC) Criterion Maximum Concentration (CMC) of 1.4 ug/l for the protection of freshwater aquatic life uses (USEPA, 2002).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

132874

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 10 fish were aggregated into 1 annual averages, which consisted of 2 fish species (1 composite(s) of Largemouth Bass each composed of 6 fish per composite, 4 composite(s) of Largemouth Bass each composed of 1 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRIDG1.

Temporal Representation:

Data for this line of evidence were collected between 2004-12-07 and 2004-12-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

132827

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Sportfish Rivers and Streams data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 7 fish were aggregated into 1 annual averages, which consisted of 1 fish species (7 composite(s) of Largemouth Bass each composed of 1 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

133108

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 10 fish were aggregated into 1 annual averages, which consisted of 2 fish species (4 composite(s) of Largemouth Bass each composed of 1 fish per composite, 1 composite(s) of Largemouth Bass each composed of 6 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRIDG1.

Temporal Representation:

Data for this line of evidence were collected between 2004-12-07 and 2004-12-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

132823

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 3 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 10 fish were aggregated into 1 annual averages, which consisted of 2 fish species (1 composite(s) of Bluegill each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 5 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-28 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

133340

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 3 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 10 fish were aggregated into 1 annual averages, which consisted of 2 fish species (1 composite(s) of Bluegill each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 5 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-28 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71477, Mercury	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

133276

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 12 fish were aggregated into 1 annual averages, which consisted of 3 fish species (1 composite(s) of Channel Catfish each composed of 2 fish per composite, 8 composite(s) of Largemouth Bass each composed of 1 fish per composite, 2 composite(s) of Striped Bass each composed of 1 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-22 and 2014-11-04

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104410	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Merphos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29496 received a use rating of insufficient in a previous assessment cycle because no evaluation guideline was available for this pollutant. None of the samples exceeded the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of three water samples exceeded the USEPA expected safe lifetime exposure limit in drinking water, calculated using the IRIS Reference Dose. None of 15 dissolved fraction water samples collected years 2002-2004 exceeded the guideline as no evaluation guidelines for the dissolved fractions for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. The sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104410, Merphos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29496

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos, Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104410, Merphos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128350

Pollutant:

Merphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA expected safe lifetime exposure limit in drinking water for Merphos, calculated using the IRIS Reference Dose, is 0.2 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.00003 mg/kg/day as the reference dose.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	103932	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Methidathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess these pollutants. None of samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 15 dissolved fraction samples (collected 2002-2004) exceeded as no evaluation guideline for the dissolved fractions for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. None of six total fraction samples (collected 2005-2008) exceeded the USEPA Office of Pesticide Programs Ecotoxicity database aquatic life MATC. None of three total fraction samples (collected 2010-2011) exceeded the USEPA Aquatic Life Benchmark. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103932, Methidathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128356

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103932, Methidathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35361

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life MATC for Methidathion is 0.86 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103932, Methidathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

129063

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103932, Methidathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29493

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70799	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Methoxychlor
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction water samples exceeded the drinking water MCL. None of six total fraction water samples exceeded the National Recommended Water Quality Criteria criterion continuous concentration. None of four total fraction water samples exceeded the National Recommended Water Quality Criteria, the maximum (instantaneous) concentration. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70799, Methoxychlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127295

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

According to the National Recommended Water Quality Criteria, the maximum (instantaneous) criteria to protect aquatic life from levels of mirex in water is 0.03 ug/l.

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70799, Methoxychlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7693

Pollutant:

Cadmium | Lead | Lindane/gamma Hexachlorocyclohexane (gamma-HCH) | Methoxychlor | Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70799, Methoxychlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70799, Methoxychlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35551

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The criterion continuous concentration for Methoxychlor is 0.3 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70799, Methoxychlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128690

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Methoxychlor is 0.03 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70799, Methoxychlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35531

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Methoxychlor is 30 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70799, Methoxychlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128691

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

According to the National Recommended Water Quality Criteria, the maximum (instantaneous) criteria to protect aquatic life from levels of mirex in water is 0.03 ug/l.

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70799, Methoxychlor	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7628

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen water samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the USEPA criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

USEPA Drinking Water Criteria of 40 ug/l for the protection of drinking water uses (USEPA, 2002).

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	78125	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Methyl Parathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Seven lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of seven sediment samples exceeded the median lethal concentration (LC50). None of nine water samples exceeded the California Department of Fish and Game instantaneous criteria. Two samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. The sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78125, Methyl Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127961

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Department of Fish and Game instantaneous criteria for Methyl Parathion is 0.08 ug/L.

Guideline Reference:

Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System

Spatial Representation:

Data was collected from 2 station(s): (Station Codes 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78125, Methyl Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128232

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Parathion, Methyl as a drinking water level is a concentration of 0.001 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78125, Methyl Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35465

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al. (2011).

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78125, Methyl Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126970

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Department of Fish and Game instantaneous criteria for Methyl Parathion is 0.08 ug/L.

Guideline Reference:

Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System

Spatial Representation:

Data was collected from 2 station(s): (Station Codes 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78125, Methyl Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35596

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The California Department of Fish and Game instantaneous criteria for Methyl Parathion is 0.08 ug/L.

Guideline Reference:

Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78125, Methyl Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

132681

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78125, Methyl Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

132676

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	69888	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Methyl Tertiary-Butyl Ether (MTBE)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. LOE 7674 is replaced by LOE 7679 because it was re-assessed using a different objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the secondary drinking water MCL. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 69888, Methyl Tertiary-Butyl Ether (MTBE)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7679

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 69888, Methyl Tertiary-Butyl Ether (MTBE)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126910

Pollutant:

Methyl Tertiary-Butyl Ether (MTBE)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Secondary California Maximum Contaminant Level for MTBE is 0.005 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 69888, Methyl Tertiary-Butyl Ether (MTBE)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35657

Pollutant:

Methyl Tertiary-Butyl Ether (MTBE)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The California Secondary MCL for MTBE is 0.005 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR title 22 section 64449.

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	78824	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Mirex
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 and 3.5 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Ten water samples and six fish tissue sampels were collected but none of them were used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy. These sample size are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78824, Mirex	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128474

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mirex. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The criterion continuous concentration for Mirex is 0.001 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78824, Mirex	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126283

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP Sportfish Rivers and Streams data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Mirex. Although data was collected for 1 fish species (1 composite(s) of Common Carp each composed of 5 fish per composite), all 1 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for mirex in fish tissue is 0.28 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; OEHHA, 1992)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Expedited Cancer Potency Values and Proposed Regulatory Levels for Certain Proposition 65 Carcinogens.

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78824, Mirex	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126663

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Mirex. Although data was collected for 4 fish species (1 composite(s) of Channel Catfish each composed of 2 fish per composite, 1 composite(s) of Common Carp each composed of 5 fish per composite, 1 composite(s) of Flathead Catfish each composed of 5 fish per composite, 1 composite(s) of Striped Bass each composed of 5 fish per composite), all 4 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Expedited Cancer Potency Values and Proposed Regulatory Levels for Certain Proposition 65 Carcinogens.

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78824, Mirex	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45988

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Mirex. One composite (6 fish per composite) were generated from one species: largemouth bass. One sample was not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for mirex in fish tissue is 0.28 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Expedited Cancer Potency Values and Proposed Regulatory Levels for Certain Proposition 65 Carcinogens.

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78824, Mirex	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127976

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mirex. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The criterion continuous concentration for Mirex is 0.001 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78824, Mirex	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35591

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The criterion continuous concentration for Mirex is 0.001 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	71332	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Molinate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction water samples exceeded the drinking water MCL. None of nine total fraction water samples exceeded the drinking water MCL or USEPA Aquatic Life Benchmark (including the samples not exceeding the MATC.) This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71332, Molinate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128580

Pollutant:

Molinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Molinate is the USEPA Aquatic Life Benchmark of 105 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 71332, Molinate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35616

Pollutant:

Molinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Molinate is 20 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71332, Molinate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128153

Pollutant:

Molinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Molinate is 0.02 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71332, Molinate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35634

Pollutant:

Molinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life MATC for Molinate is 0.6 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 71332, Molinate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71332, Molinate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127677

Pollutant:

Molinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Molinate is the USEPA Aquatic Life Benchmark of 105 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	70393	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Naphthalene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Eight lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 24 sediment samples exceeded the sediment quality guideline. None of eight water samples exceeded the California State Notification Level. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70393, Naphthalene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70393, Naphthalene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125598

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Naphthalene from MacDonald et al., 2000a which states that the probable effect concentration for Naphthalene is 561 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70393, Naphthalene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125599

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Naphthalene from MacDonald et al., 2000a which states that the probable effect concentration for Naphthalene is 561 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70393, Naphthalene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32564

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 4 samples collected for naphthalene (Sum of c0-c4) exceeded the evaluation guideline.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Probable Effect Concentration for naphthalene in freshwater sediments is 561 ug/kg.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following station: Colorado River at Imperial Dam Grates - 715CRIDG1.

Temporal Representation:

The samples were collected on 10/25/2005 - 4/22/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70393, Naphthalene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128369

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The National Recommended Ambient Water Quality Criterion for Naphthalene is 620 ug/l. (EPA 440/5-80-059)

Guideline Reference:

Ambient Water Quality Criteria for Naphthalene

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70393, Naphthalene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128370

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70393, Naphthalene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

31616

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 2 samples exceeded the California State Notification Level criterion.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain concentrations of chemical constituents shall be present in amounts that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

The California State Notification Level criterion for naphthalene is 0.017 mg/L.

Guideline Reference:

Drinking Water Notification Levels and Response Levels

Spatial Representation:

Data was collected at the following station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples were collected on 10/25/2005 and 5/3/2006.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70393, Naphthalene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128371

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The National Recommended Ambient Water Quality Criterion for Naphthalene is 620 ug/l. (EPA 440/5-80-059)

Guideline Reference:

Ambient Water Quality Criteria for Naphthalene

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	72496	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Nickel
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Sixteen lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27211 is replaced by the LOE No. 46763. LOE 7652 is replaced by the LOE No. 7674. assessed using the same water quality objective for two different beneficial uses in last assessment cycle. Thus, LOE No. 27211 is not included in the final use rating. None of other samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 water samples exceeded the CTR CMC and none of 16 exceeded CTR CCC criteria for the protection of freshwater aquatic life uses. None of 25 sediment samples exceeded the sediment quality guideline. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127662

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Nickel criteria for the protection of human health from consumption of organisms only is 4600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128741

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7637

Pollutant:

Lead | Nickel | Silver | Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35662

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Nickel criteria for the protection of human health from consumption of organisms only is 4,600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32940

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples exceeded the hardness based criteria calculated for nickel.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at station 715CRIDG1 (Colorado River at Imperial Dam Grates)

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125789

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Nickel from MacDonald et al., 2000a which states that the probable effect concentration for Nickel is 48.6 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35362

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125788

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Nickel from MacDonald et al., 2000a which states that the probable effect concentration for Nickel is 48.6 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128743

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35682

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 72496, Nickel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128742

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	71053	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Nitrogen, Nitrate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 17 "Nitrate" "dissolved" fraction water samples exceeded the drinking water MCL for Nitrate. Zero of six "Nitrate" "none" fraction water samples exceeded the drinking water MCL for Nitrate for Nitrate as N. Zero of one "Nitrogen, Nitrate" "dissolved" fraction water samples exceeded the drinking water MCL for Nitrate as N. Zero of two "Nitrogen, Nitrate" "not recorded" fraction water samples exceeded the drinking water MCL for Nitrate as N. Zero of seven "Nitrogen, Nitrate" "total" fraction water samples exceeded the drinking water MCL for Nitrate as N. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71053, Nitrogen, Nitrate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127894

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Nitrate as N is 10000 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71053, Nitrogen, Nitrate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71053, Nitrogen, Nitrate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127474

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Nitrate as N is 10000 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71053, Nitrogen, Nitrate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127892

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Nitrate as N is 10000 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2010-10-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71053, Nitrogen, Nitrate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35367

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nitrate (as N) is 10 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	71430	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Nitrogen, Nitrite
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 27 "Nitrogen, Nitrite" dissolved fraction water samples and none of six "Nitrite as Nitrite NO2" "none" fraction water samples exceeded the drinking water MCL for Nitrite as N of 1.0 mg/L. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71430, Nitrogen, Nitrite	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71430, Nitrogen, Nitrite	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128312

Pollutant:

Nitrogen, Nitrite

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71430, Nitrogen, Nitrite	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35535

Pollutant:

Nitrite as Nitrite NO2

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	103954	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Oxadiazon
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of four total fraction water samples exceeded the USEPA Aquatic Life Benchmark for a nonvascular plant (acute). None of 15 dissolved fraction water samples (collected 2002-2005) exceeded the objective as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. None of 15 sediment samples (collected 2002-2005) exceeded the objective as no evaluation guideline for the sediment fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103954, Oxadiazon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29574

Pollutant:

Dacthal | Mirex | Oxadiazon

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Dacthal, Mirex, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 103954, Oxadiazon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128992

Pollutant:

Oxadiazon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Oxadiazon is the USEPA Aquatic Life Benchmark of 5.2 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103954, Oxadiazon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128995

Pollutant:

Oxadiazon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA expected safe lifetime exposure limit in drinking water for Oxdiazon, calculated using the IRIS Reference Dose, is 35 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.005 mg/kg/day as the reference dose.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103954, Oxadiazon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128993

Pollutant:

Oxadiazon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Oxadiazon is the USEPA Aquatic Life Benchmark of 5.2 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 103954, Oxadiazon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29809

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	78335	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Oxygen, Dissolved
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. LOE No. 129074 is replaced by LOE No. 128160 as the Alamo River is listed in the Basin Plan as having the "Warm Freshwater Habitat" beneficial use as opposed to the "Cold Freshwater Habitat" beneficial use. None of the samples exceed the water quality objective for the "Warm Freshwater Habitat" beneficial use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 16 water samples exceeded the Basin Plan objective for the "Warm Freshwater Habitat" beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 78335, Oxygen, Dissolved	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32342

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of the five samples exceeded the water quality objective for dissolved oxygen.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

From the Colorado River Water Quality Control Plan 'The dissolved Oxygen concentration shall not be reduced below the following minimum levels at any time: for waters designated as WARM-5.0 mg/L.'

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at station 715CRIDG1 - Colorado River at Imperial Dam Grates.

Temporal Representation:

The samples were collected during October 2005, May 2006, May 2007, October 2007, and April 2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78335, Oxygen, Dissolved	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

129074

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Colorado River Basin, Cold Water Habitat Objective, Chapter III, states the following: The dissolved oxygen concentration for cold water habitats shall not be reduced below 8.0 mg/l at any time.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78335, Oxygen, Dissolved	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128160

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Colorado River Basin, WARM Water Habitat Objective, Chapter III, states the following: The dissolved oxygen concentration for cold water habitats shall not be reduced below 5.0 mg/l at any time.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	78589	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	PAHs (Polycyclic Aromatic Hydrocarbons)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of eight sediment samples exceeded the sediment quality guideline and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 78589, PAHs (Polycyclic Aromatic Hydrocarbons)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125510

Pollutant:

PAHs (Polycyclic Aromatic Hydrocarbons)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Total PAHs from MacDonald et al., 2000a which states that the probable effect concentration for Total PAHs is 22800 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78589, PAHs (Polycyclic Aromatic Hydrocarbons)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125452

Pollutant:

PAHs (Polycyclic Aromatic Hydrocarbons)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Total PAHs from MacDonald et al., 2000a which states that the probable effect concentration for Total PAHs is 22800 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78589, PAHs (Polycyclic Aromatic Hydrocarbons)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35456

Pollutant:

PAHs (Polycyclic Aromatic Hydrocarbons)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for fluoranthene is 2230 ug/kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	71431	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	PCBs (Polychlorinated biphenyls)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollution

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1, 3.5 and 3.6 of the Listing Policy. Under sections 3.1 and 3.5 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Fourteen lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 17 dissolved fraction and zero of seven total fraction water samples exceeded the California drinking water MCL and CTR respectively. Zero of 24 sediment samples exceeded the sediment quality guideline. One of three fish tissue sample exceeded the OEHHA fish contaminant goal. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126582

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total PCB concentration of 500 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-22 and 2014-10-22

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45997

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for PCB, Total. One composite (6 fish per composite) were generated from one species: Largemouth Bass. Total PCB was assessed for as follows: PCB aroclors and congeners were summed separately and the sum that yielded the highest value was used for the assessment.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for polychlorinated biphenyls in fish tissue is 2.6 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126584

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-22 and 2014-10-22

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126353

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-22 and 2014-10-22

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33414

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 2 samples exceeded the criterion continuous concentration for total PCB. The water body was assessed for the 3 aroclors that were contained within the data set and they include aroclor 1248, aroclor 1254, and aroclor 1260.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The total PCB criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.014 ug/L. This value corresponds to the sum of aroclors 1242, 1254, 1221, 1232, 1248, 1260, and 1016 (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 4/22/2008 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125691

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Total PCBs from MacDonald et al., 2000a which states that the probable effect concentration for Total PCBs is 676 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33420

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 4 samples collected for Total PCBs exceeded the evaluation guideline.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for total PCB is 676 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

The samples were collected on 10/25/2005, 5/3/2006, 10/23/2007 and 4/22/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125662

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Total PCBs from MacDonald et al., 2000a which states that the probable effect concentration for Total PCBs is 676 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127736

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The PCB, total Congeners criteria for the protection of human health from consumption of organisms only is 0.00017 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

129083

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The PCBs criteria for the protection of human health from the consumption of water and organisms is 0.00017 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32995

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The method detection limit for all the non-detect samples was greater than the criteria: thus the data was not used in this assessment.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The total PCB criterion for the protection of human health from the consumption of water and organisms is 0.00017 ug/L. This value corresponds to total PCBs, eg., the sum of all congener or isomer or homolog or aroclor analyses (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples were collected on 10/25/2005, 5/3/2006, 5/8/2007, 10/23/2007, 4/22/2008, and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71431, PCBs (Polychlorinated biphenyls)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45998

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for PCB, Total. One composite (6 fish per composite) were generated from one species: Largemouth Bass. Total PCB was assessed for as follows: PCB aroclors and congeners were summed separately and the sum that yielded the highest value was used for the assessment.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	103994	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Parathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Five lines of evidence are available in the administrative record to assess these pollutants. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 sediment samples and zero of 15 dissolved fraction water samples exceeded the objective as no evaluation guideline for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. Eleven total fraction water samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103994, Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29493

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 103994, Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29572

Pollutant:

Methyl Parathion | Parathion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Parathion, or Methyl Parathion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 103994, Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35557

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The criterion continuous concentration for Parathion, Ethyl is 0.013 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 103994, Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128500

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Ethyl. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The criterion continuous concentration for Parathion, Ethyl is 0.013 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 103994, Parathion	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128929

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Ethyl. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The criterion continuous concentration for Parathion, Ethyl is 0.013 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	74033	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Perchlorate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. In a previous cycle, LOE No. 7615 received a use rating of insufficient because a remedial effort has been underway since October 2002 to remove perchlorate from a source near Henderson; thus, monitoring data collected up to October 2002 are no longer representative of perchlorate in the River. Current data indicate no samples exceedances. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Two out of 17 water samples exceeded the drinking water MCL used to interpret the water quality objective in October 2002 and this exceeds the allowable frequency calculated from the equation in Table 3.1 of the Listing Policy. Monitoring data collected up to October 2002 are no longer representative of perchlorate in the River because a remedial effort has been underway to remove perchlorate from a source near Henderson, NV since October 2002. Data collected since then indicate no samples exceedances. Combining the "none" and "not recorded" fractions with "dissolved" or "total" fraction, two of 25 "dissolved" or 32 "total" fraction water samples exceeded the water quality objective. This does not exceed the allowable frequency of the Listing Policy in Table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 74033, Perchlorate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128783

Pollutant:

Perchlorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Perchlorate is 0.006 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 74033, Perchlorate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128781

Pollutant:

Perchlorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Perchlorate is 0.006 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 74033, Perchlorate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7615

Pollutant:

Perchlorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen water samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, 2 exceeded the CDPH MCL (SWAMP, 2007). The exceedences were found in samples collected on 10/01/2002 at Taylor Lake, and 10/02/02 at Parker Dam (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Level (MCL) of 0.006 mg/l for the protection of human health (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 74033, Perchlorate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35601

Pollutant:

Perchlorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Perchlorate is 6 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 74033, Perchlorate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127145

Pollutant:

Perchlorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Perchlorate is 0.006 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2010-10-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	78590	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Permethrin, total
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Six lines of evidence are available in the administrative record to assess this pollutant. One of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of eight sediment samples exceeded the median lethal concentration (LC50). Zero of four water samples exceeded the UC Davis Aquatic Life Criteria. Four additional water samples were collected, but the results were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy. The sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 78590, Permethrin, total	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35494

Pollutant:

Permethrin, total

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78590, Permethrin, total	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127398

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of permethrin does not exceed 0.002 ug/L and if the 1-h average concentration does not exceed 0.01 ug/L. Mixtures of permethrin and other pyrethroids should be considered in an additive manner. (Fojut et al. 2012)

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRPDDM, 715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78590, Permethrin, total	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127401

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRPDDM, 715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78590, Permethrin, total	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125528

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78590, Permethrin, total	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46456

Pollutant:

Permethrin, total

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Permethrin, Total. Four sample results were not used in the assessment because the laboratory data reporting limit(s) was above the objective (0.002 ug/L) and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/23/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78590, Permethrin, total	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125616

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70446	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Phenanthrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 27 sediment samples exceeded the sediment quality guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70446, Phenanthrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125661

Pollutant:

Phenanthrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Phenanthrene from MacDonald et al., 2000a which states that the probable effect concentration for Phenanthrene is 1170 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70446, Phenanthrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125492

Pollutant:

Phenanthrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Phenanthrene from MacDonald et al., 2000a which states that the probable effect concentration for Phenanthrene is 1170 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70446, Phenanthrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70446, Phenanthrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32824

Pollutant:

Phenanthrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 4 samples collected for Phenanthrene (sum of c0-c4) exceeded the evaluation guideline.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Probable Effect Concentration for Phenanthrene in freshwater sediments is 1170 ug/kg.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following stations: Colorado River at Imperial Dam Grates - 715CRIDG1.

Temporal Representation:

The samples were collected on 10/25/2005 - 4/21/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	104022	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Phorate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess these pollutants. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of six water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50. None of three water samples exceeded the USEPA Aquatic Life Benchmark. These sample size are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 104022, Phorate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127414

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104022, Phorate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127849

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104022, Phorate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35621

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50 for Phorate is 2 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):


DECISION ID	104034	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Phosmet
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess these pollutants. None of samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 15 dissolved fraction water samples collected and analyzed from 5/2002 through 5/2004 exceeded the objective as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. None of six water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database aquatic life LC50. None of three water samples exceeded the USEPA Aquatic Life Benchmark. The sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104034, Phosmet	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35664

Pollutant:

Phosmet

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Phosmet is 5.6 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104034, Phosmet	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29499

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104034, Phosmet	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128617

Pollutant:

Phosmet

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104034, Phosmet	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128615

Pollutant:

Phosmet

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	104047	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Prometon (Prometone)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of nine total fraction water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database aquatic life LC50 or the USEPA Aquatic Life Benchmark. None of three total fraction water samples exceeded the USEPA Health Advisory. None of 14 dissolved fraction water samples collected and analyzed from 5/2002 through 5/2004 exceeded the objective as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11] of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 104047, Prometon (Prometone)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127465

Pollutant:

Prometon (Prometone)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Prometon is the USEPA Aquatic Life Benchmark of 98 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104047, Prometon (Prometone)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128386

Pollutant:

Prometon (Prometone)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA Health Advisory for 10 day exposure of a 10 kg-Child to Prometon as a drinking water level is a concentration of 0.02 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104047, Prometon (Prometone)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127463

Pollutant:

Prometon (Prometone)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Prometon is the USEPA Aquatic Life Benchmark of 98 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104047, Prometon (Prometone)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29502

Pollutant:

Atroton | Prometon (Prometone) | Secbumeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fourteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Atroton, Prometon, or Secbumeton for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104047, Prometon (Prometone)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35689

Pollutant:

Prometon (Prometone)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Prometon is 98 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):


DECISION ID	104051	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Prometryn
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 14 dissolved fraction water samples collected 2002-2004 exceeded the objective as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. None of six total fraction water samples collected 2005-2008 exceeded the USEPA Office of Pesticide Programs Ecotoxicity database aquatic life EC50 of 1 ug/L. None of three total fraction and one dissolved fraction water samples collected 2010-2011 exceeded the or the USEPA Aquatic Life Benchmark of 1.04 ug/L. Thus, none of nine total fraction and one dissolved fraction water samples collected 2005-2011 exceeded the or the USEPA Aquatic Life Benchmark of 1.04 ug/L. The sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104051, Prometryn	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

129018

Pollutant:

Prometryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Prometryn is the USEPA Aquatic Life Benchmark of 1.04 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104051, Prometryn	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

129017

Pollutant:

Prometryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Prometryn is the USEPA Aquatic Life Benchmark of 1.04 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104051, Prometryn	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35540

Pollutant:

Prometryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Prometryn is 1 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104051, Prometryn	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128601

Pollutant:

Prometryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA expected safe lifetime exposure limit in drinking water for Prometryn, calculated using the IRIS Reference Dose, is 28 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.004 mg/kg/day as the reference dose.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104051, Prometryn	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29501

Pollutant:

Ametryn | Prometryn | Simetryn | Terbutryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fourteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ametryn, Prometryn, Simetryn, or Terbutryn for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104078	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Propazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 14 dissolved fraction water samples collected 2002-2004 exceeded the objective as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. None of six total fraction water samples collected 2005-2008 exceeded the USEPA Office of Pesticide Programs Ecotoxicity database aquatic life EC50. None of three total fraction water samples collected 2010-2011 exceeded the or the USEPA Aquatic Life Benchmark. The sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104078, Propazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126967

Pollutant:

Propazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Propazine is the USEPA Aquatic Life Benchmark of 24.8 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104078, Propazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126968

Pollutant:

Propazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Propazine is the USEPA Aquatic Life Benchmark of 24.8 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104078, Propazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35581

Pollutant:

Propazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Propazine is 25 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104078, Propazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29503

Pollutant:

Propazine | Terbuthylazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fourteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Propazine, or Terbuthylazine for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70746	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Pyrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Eight lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 25 sediment samples exceeded the sediment quality guidelines. None of 17 dissolved fraction water samples exceeded the California Toxics Rule Criteria. None of 4 total fraction water samples exceeded the California Toxics Rule Criteria. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70746, Pyrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70746, Pyrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128208

Pollutant:

Pyrene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Pyrene criteria for the protection of human health from consumption of organisms only is 11,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70746, Pyrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125605

Pollutant:

Pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Pyrene is 1520 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70746, Pyrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35440

Pollutant:

Pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for pyrene is 1520 ug/kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70746, Pyrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70746, Pyrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128209

Pollutant:

Pyrene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Pyrene criteria for the protection of human health from the consumption of water and organisms is 960 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70746, Pyrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7696

Pollutant:

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70746, Pyrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125804

Pollutant:

Pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Pyrene is 1520 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104094	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Pyrethrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of eight water samples exceeded the or the USEPA Aquatic Life Benchmark for Pyrethrin-1 or Pyrethrin-2. The sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104094, Pyrethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127439

Pollutant:

Pyrethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Pyrethrin-1 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104094, Pyrethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128337

Pollutant:

Pyrethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Pyrethrin-2 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104094, Pyrethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127716

Pollutant:

Pyrethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Pyrethrin-2 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104094, Pyrethrin	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127440

Pollutant:

Pyrethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Pyrethrin-1 is the USEPA Aquatic Life Benchmark of 0.86 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	104102	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Pyrethroids
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Four lines of evidence are available in the administrative record to assess this pollutant. One of the samples exceed the objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of eight sediment samples exceeded the sediment quality guidelines. One of four water samples exceeded the Department of Fish and Game Aquatic Life Criteria / UC Davis Aquatic Life Criteria. The sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104102, Pyrethroids	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125846

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of; Bifenthrin, Cyfluthrin, Cypermethrin, Lambda-Cyhalothrin, and Permethrin, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample day is considered to be in exceedance of the water quality standard. (Department of Fish and Game Aquatic Life Criteria for Pyrethroid Insecticides, 2000)

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data were collected from 4 (Station Codes: 715CRIDG1, 715CRSQLK, 715CRPDDM, 715CRIDU1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104102, Pyrethroids	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125704

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data were collected from 4 (Station Codes: 715CRIDG1, 715CRSQLK, 715CRPDDM, 715CRIDU1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104102, Pyrethroids	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128163

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of; Bifenthrin, Cyfluthrin, Cypermethrin, Lambda-Cyhalothrin, deltamethrin, and Permethrin, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample day is considered to be in exceedance of the water quality standard. (Department of Fish and Game Aquatic Life Criteria for Pyrethroid Insecticides, 2000, UC Davis Aquatic Life Criteria for Pyrethroid Insecticides, 2012)

Guideline Reference:

Aquatic Life Criteria for Pyrethroid Insecticides (DFG Administrative Report 00-6, 2000)

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104102, Pyrethroids	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127373

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of; Bifenthrin, Cyfluthrin, Cypermethrin, Lambda-Cyhalothrin, deltamethrin, and Permethrin, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample day is considered to be in exceedance of the water quality standard. (Department of Fish and Game Aquatic Life Criteria for Pyrethroid Insecticides, 2000, UC Davis Aquatic Life Criteria for Pyrethroid Insecticides, 2012)

Guideline Reference:

Aquatic Life Criteria for Pyrethroid Insecticides (DFG Administrative Report 00-6, 2000)

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	71487	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Selenium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1, 3.5 and 3.6 of the Listing Policy. Under sections 3.1 and 3.5 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Eleven lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 15 sediment samples collected 2002-2004 exceeded the sediment quality guideline as no evaluation guideline for the sediment fraction for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. None of 12 fish tissue samples exceeded the OEHHA fish contaminant goal. None of 38 total fraction and none of ten dissolved fraction water samples exceeded the California Toxics Rule Criteria. None of 38 total fraction and none of 27 dissolved fraction water samples exceeded the California drinking water MCL. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71487, Selenium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125985

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71487, Selenium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125986

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71487, Selenium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126061

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for selenium in the Basin Plan is 0.05 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 71487, Selenium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

30277

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guideline for the sediment fraction of Selenium for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71487, Selenium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126248

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows 0 of the 9 samples exceeded the water quality standard for Selenium. Data were collected for 7 fish species (1 composite(s) of Flathead Catfish each composed of 5 fish per composite, 1 composite(s) of Channel Catfish each composed of 2 fish per composite, 1 composite(s) of Common Carp each composed of 5 fish per composite, 5 composite(s) of Striped Bass each composed of 1 fish per composite, 1 composite(s) of Bluegill each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 5 fish per composite, 1 composite(s) of Largemouth Bass each composed of 5 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The OEHHA Fish Contaminant Goal for selenium in fish tissue is 7.4 ppm. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A background dietary consumption rate of 0.114 mg/day is applied for this micronutrient. (Klasing, S., and R. Brodberg, 2008)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-11-04

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71487, Selenium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45999

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71487, Selenium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126435

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71487, Selenium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

129008

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71487, Selenium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

129007

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for selenium in the Basin Plan is 0.05 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71487, Selenium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

129005

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71487, Selenium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	71435	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Silver
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the 33 samples exceeded the California Toxics Rule criteria or MCL and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71435, Silver	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7679

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71435, Silver	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7693

Pollutant:

Cadmium | Lead | Lindane/gamma Hexachlorocyclohexane (gamma-HCH) | Methoxychlor | Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71435, Silver	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128721

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for silver is 0.1 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71435, Silver	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128722

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71435, Silver	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35602

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The California Secondary MCL for silver is 0.1 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR title 22 section 64449.

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71435, Silver	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32961

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples exceeded the hardness based criteria calculated for silver.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion maximum concentrations (1-hour average) to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71435, Silver	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127526

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71435, Silver	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7637

Pollutant:

Lead | Nickel | Silver | Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70849	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Simazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of three total fraction water samples exceeded the USEPA Aquatic Life Benchmark. None of 16 dissolved fraction and none of nine total fraction water samples exceeded the drinking water MCL. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70849, Simazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35625

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Simazine is 4 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70849, Simazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35622

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Simazine is 90 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 70849, Simazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126989

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Simazine is the USEPA Aquatic Life Benchmark of 2.24 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 70849, Simazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126988

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Simazine is the USEPA Aquatic Life Benchmark of 2.24 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 70849, Simazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126990

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Simazine is 0.004 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70849, Simazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7672

Pollutant:

Atrazine | Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):


DECISION ID	79529	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Sulfates
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 49 dissolved fraction and none of six total fraction water samples exceeded the California Secondary MCL. This does not exceed the allowable frequency of the Listing Policy in Table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 79529, Sulfates	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126042

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 39 samples exceeded the water quality standard for Sulfate.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance of 500 mg/l.

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2017-03-10

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 79529, Sulfates	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34568

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples were greater than the Secondary MCLs objective.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Secondary Maximum Contaminant Levels (SMCLs) apply to ambient waters under the Colorado River Basin Region's narrative "Chemical Constituents" objective. The SMCL for Sulfates (SO4) is 500 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at stations 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 79529, Sulfates	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127199

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance of 500 mg/l.

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104422	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Temperature, water
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2, a single line(s) of evidence is necessary to assess listing status. One line(s) of evidence is available in the administrative record to assess this pollutant. Two water samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Two of 11 samples exceed the evaluation guideline for Inland Fishes of California (Moyle 1976). This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples is needed to determine if a beneficial use is fully supported using table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104422, Temperature, water	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128298

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104151	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Terbufos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this sections a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceeded the objectives. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 15 dissolved fraction water samples exceeded the objective as no evaluation guidelines for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Zero of zero total fraction water samples exceeded the USEPA Aquatic Life Benchmark. The six samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104151, Terbufos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128949

Pollutant:

Terbufos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Terbufos. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Terbufos is the USEPA Aquatic Life Benchmark of 0.03 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104151, Terbufos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128948

Pollutant:

Terbufos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Terbufos. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Terbufos is the USEPA Aquatic Life Benchmark of 0.03 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 715CRIDG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104151, Terbufos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29500

Pollutant:

Benzo(e)Pyrene (4,5-benzopyrene) | Benzo[g,h,i]perylene | Biphenyl | Terbufos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, Biphenyl, or Terbufos for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104154	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Terbuthylazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Three lines of evidence are available in the administrative record to assess these pollutants. None of the samples exceeded the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of three total fraction water samples exceeded the USEPA Aquatic Life Benchmark. Zero of 14 dissolved fraction water samples collected 2002-2004 exceeded the objective as no evaluation guidelines for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104154, Terbuthylazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127220

Pollutant:

Terbuthylazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Terbuthylazine is the USEPA Aquatic Life Benchmark of 1800 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104154, Terbuthylazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127389

Pollutant:

Terbuthylazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Terbuthylazine is the USEPA Aquatic Life Benchmark of 1800 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104154, Terbuthylazine	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29503

Pollutant:

Propazine | Terbuthylazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fourteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Propazine, or Terbuthylazine for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104408	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Terbutryn
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29501 received a use rating of insufficient in a previous assessment cycle because no evaluation guideline was available for this pollutant. None of the samples exceeded the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of three water samples exceeded the USEPA expected safe lifetime exposure limit in drinking water for Terbutryn, calculated using the IRIS Reference Dose. None of 14 dissolved fraction water samples collected years 2002-2004 exceeded the guideline as no evaluation guidelines for the dissolved fractions for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. The sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104408, Terbutryn	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29501

Pollutant:

Ametryn | Prometryn | Simetryn | Terbutryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fourteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ametryn, Prometryn, Simetryn, or Terbutryn for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104408, Terbutryn	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127228

Pollutant:

Terbutryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA expected safe lifetime exposure limit in drinking water for Terbutryn, calculated using the IRIS Reference Dose, is 7 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.001 mg/kg/day as the reference dose.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	70082	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Tetrachloroethylene/PCE
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. LOE No. 7674 is replaced by the LOE No. 7649 and LOE No. 27212 is replaced by the LOE No. 46761 because they were re-assessed with a different objective. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of two tottal fraction water samples exceeded the California Toxics Rule criteria for the protection of human health from consumption of organisms.. None of 11 dissolved fraction and none of six tottal fraction water samples exceeded the California Toxics Rule criteria for the protection of human health from consumption of organisms and water. Four dissolved fraction water samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70082, Tetrachloroethylene/PCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35374

Pollutant:

Tetrachloroethylene/PCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Tetrachloroethylene criteria for the protection of human health from consumption of organisms only is 8.85 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70082, Tetrachloroethylene/PCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127698

Pollutant:

Tetrachloroethylene/PCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Tetrachloroethylene criteria for the protection of human health from consumption of organisms only is 8.85 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70082, Tetrachloroethylene/PCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7649

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70082, Tetrachloroethylene/PCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35378

Pollutant:

Tetrachloroethylene/PCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Tetrachloroethylene criteria for the protection of human health from the consumption of water and organisms is 0.8 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70082, Tetrachloroethylene/PCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127930

Pollutant:

Tetrachloroethylene/PCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Tetrachloroethylene. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Tetrachloroethylene criteria for the protection of human health from the consumption of water and organisms is 0.8 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70082, Tetrachloroethylene/PCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46761

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen samples were taken at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70082, Tetrachloroethylene/PCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27212

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70082, Tetrachloroethylene/PCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104409	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Tetrachlorvinphos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29496 received a use rating of insufficient in a previous assessment cycle because no evaluation guideline was available for this pollutant. None of the samples exceeded the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of three water samples exceeded the USEPA expected safe lifetime exposure limit in drinking water, calculated using the IRIS Reference Dose. None of 15 dissolved fraction water samples collected years 2002-2004 exceeded the guideline as no evaluation guidelines for the dissolved fractions for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy. The sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104409, Tetrachlorvinphos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29496

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos, Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104409, Tetrachlorvinphos	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127239

Pollutant:

Tetrachlorvinphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The USEPA expected safe lifetime exposure limit in drinking water for Tetrachlorvinphos, calculated using the IRIS Reference Dose, is 210 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.03 mg/kg/day as the reference dose.

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	104157	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Thiobencarb
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of 9 total fraction water samples exceeded either the secondary drinking water MCL and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. The sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104157, Thiobencarb	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104157, Thiobencarb	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35383

Pollutant:

Thiobencarb/Bolero

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life MATC for Thiobencarb is 1.4 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104157, Thiobencarb	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35387

Pollutant:

Thiobencarb/Bolero

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The California Secondary MCL for thiobencarb is 0.001 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR title 22 section 64449.

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 104157, Thiobencarb	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128597

Pollutant:

Thiobencarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Thiobencarb is the USEPA Aquatic Life Benchmark of 1 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104157, Thiobencarb	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128596

Pollutant:

Thiobencarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for thiobencarb is 0.001 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104157, Thiobencarb	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7679

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104157, Thiobencarb	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128440

Pollutant:

Thiobencarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Thiobencarb is the USEPA Aquatic Life Benchmark of 1 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	71518	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Toluene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. LOE No. 7652 is replaced by LOE No. 128446 and LOE No. 27211 is replaced by LOE No. 46763 because it was re-assessed with a different guideline. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the California Toxics Rule criteria. and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71518, Toluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35397

Pollutant:

Toluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Toluene is 150 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71518, Toluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128446

Pollutant:

Toluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Toluene is 0.15 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71518, Toluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126953

Pollutant:

Toluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Toluene criteria for the protection of human health from consumption of organisms only is 200,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71518, Toluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71518, Toluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71518, Toluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71518, Toluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71518, Toluene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35393

Pollutant:

Toluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Toluene criteria for the protection of human health from consumption of organisms only is 200,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104419	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Trichlorfon
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of three total fraction samples exceeded the reference dose. (National Academy of Sciences Drinking Water and Health, Volume 6, 1986) . Zero of 15 dissolved fraction water samples collected 2002-2004 exceeded the guideline as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104419, Trichlorfon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29499

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104419, Trichlorfon	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128467

Pollutant:

Trichlorfon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The acceptable daily intake for Trichlorfon is 26 ug/l. This was calculated for a child assuming 10 kg body weight, 1 liter/day water consumption, 20% relative source contribution from drinking water, and 1.25 mg/kg/day as the reference dose. (National Academy of Sciences Drinking Water and Health, Volume 6, 1986)

Guideline Reference:

National Academy of Sciences Health Advisories document 1986

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70881	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Trichloroethylene/TCE
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27212 is replaced by the LOE No. 46761 and LOE No. 7674 is replaced by the LOE No. 7649 because they were re-assessed with different guidelines. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of 6 total fraction water exceeded the California Toxics Rule criteria for the protection of human health from the consumption of organisms only. None of 11 dissolved fraction and none of 6 total fraction water exceeded the California Toxics Rule criteria for the protection of human health from the consumption of water and organisms . Six dissolved fraction water sample results could not be used in this assessment because the sample results were non-detect and the detection limit was above the criteria concentration. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70881, Trichloroethylene/TCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70881, Trichloroethylene/TCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27212

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70881, Trichloroethylene/TCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7649

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70881, Trichloroethylene/TCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46761

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen samples were taken at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70881, Trichloroethylene/TCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128196

Pollutant:

Trichloroethylene/TCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Trichloroethylene criteria for the protection of human health from consumption of organisms only is 81 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70881, Trichloroethylene/TCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35402

Pollutant:

Trichloroethylene/TCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Trichloroethylene criteria for the protection of human health from consumption of organisms only is 81 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70881, Trichloroethylene/TCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35406

Pollutant:

Trichloroethylene/TCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The trichloroethylene criteria for the protection of human health from the consumption of water and organisms is 2.7 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70881, Trichloroethylene/TCE	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128797

Pollutant:

Trichloroethylene/TCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The trichloroethylene criteria for the protection of human health from the consumption of water and organisms is 2.7 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70211	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Xylenes (total) (mixed)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of 6 total fraction water samples exceeded the drinking water MCL and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70211, Xylenes (total) (mixed)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70211, Xylenes (total) (mixed)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127928

Pollutant:

Xylenes (total) (mixed)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Xylene, total is 1.75 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70211, Xylenes (total) (mixed)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33042

Pollutant:

Xylenes (total) (mixed)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Two samples were collected and no samples exceeded the objective.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. California Maximum Containment Levels are incorporated by reference through the basin plan (Colorado River Basin Plan 2006). The California MCL for Xylenes is 1.75 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at Colorado River at Imperial Dam Grates-715CRIDG1.

Temporal Representation:

Samples were collected between 10/25/2005-5/3/2006.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	78100	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Zinc
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Fifteen lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 25 sediment samples exceeded the sediment quality guideline. None of 36 dissolved fraction and none of three total fraction water samples exceeded the California Drinking Water MCL. None of 17 dissolved fraction water samples exceeded the California Toxics Rule CMC criteria. None of 21 dissolved fraction water samples exceeded the California Toxics Rule CCC criteria. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7679

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126040

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Zinc.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126036

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Zinc.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127945

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126038

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Zinc.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2013-05-29

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127943

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35409

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR title 22 section 64449.

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32567

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 6 samples exceeded the hardness based criteria calculated for zinc.

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126037

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Zinc.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127944

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125448

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Zinc from MacDonald et al., 2000a which states that the probable effect concentration for Zinc is 459 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125692

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Zinc from MacDonald et al., 2000a which states that the probable effect concentration for Zinc is 459 mg/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7625

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen sediment samples were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Consensus Based Sediment Quality Guideline Probable Effects Concentration (PEC) of 459 mg/kg for the protection of freshwater organisms to toxic effects (Macdonald et al, 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35412

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78100, Zinc	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7637

Pollutant:

Lead | Nickel | Silver | Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70271	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	alpha-Endosulfan (Endosulfan 1)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eleven lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27211 is replaced by the LOE No. 46763. None of samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of 10 total fraction water samples exceeded the CTR criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70271, alpha-Endosulfan (Endosulfan 1)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128177

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan I criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for alpha-endosulfan is 0.056 ug/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70271, alpha-Endosulfan (Endosulfan 1)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128174

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan I criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70271, alpha-Endosulfan (Endosulfan 1)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35018

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan I criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70271, alpha-Endosulfan (Endosulfan 1)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35023

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule criteria for alpha-endosulfan to protect human health for waters that include the designated use of MUN is 110 ug/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70271, alpha-Endosulfan (Endosulfan 1)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128175

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule criteria for alpha-endosulfan to protect human health for waters that include the designated use of MUN is 110 ug/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70271, alpha-Endosulfan (Endosulfan 1)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128176

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan I criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for alpha-endosulfan is 0.056 ug/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70271, alpha-Endosulfan (Endosulfan 1)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35027

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan I criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for alpha-endosulfan is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70271, alpha-Endosulfan (Endosulfan 1)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70271, alpha-Endosulfan (Endosulfan 1)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7634

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70271, alpha-Endosulfan (Endosulfan 1)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70271, alpha-Endosulfan (Endosulfan 1)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70214	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	alpha.-BHC (Benzenehexachloride or alpha-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27211 is replaced by the LOE No. 46763. None of samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of 10 total fraction water samples exceeded the CTR criteria. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70214, alpha.-BHC (Benzenehexachloride or alpha-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70214, alpha.-BHC (Benzenehexachloride or alpha-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126884

Pollutant:

Hexachlorocyclohexane (HCH), alpha

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The BHC, alpha criteria for the protection of human health from consumption of organisms only is 0.013 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70214, alpha.-BHC (Benzenehexachloride or alpha-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35136

Pollutant:

Hexachlorocyclohexane (HCH), alpha

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The BHC, alpha criteria for the protection of human health from consumption of organisms only is 0.013 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70214, alpha.-BHC (Benzenehexachloride or alpha-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128078

Pollutant:

Hexachlorocyclohexane (HCH), alpha

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The BHC, alpha criteria for the protection of human health from the consumption of water and organisms is 0.0039 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70214, alpha.-BHC (Benzenehexachloride or alpha-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35152

Pollutant:

Hexachlorocyclohexane (HCH), alpha

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The BHC, alpha criteria for the protection of human health from the consumption of water and organisms is 0.0039 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70214, alpha.-BHC (Benzenehexachloride or alpha-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70214, alpha.-BHC (Benzenehexachloride or alpha-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	79033	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	beta-BHC (Benzenehexachloride or beta-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27211 is replaced by the LOE No. 46763. None of samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of 10 total fraction water samples exceeded the CTR criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 79033, beta-BHC (Benzenehexachloride or beta-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35173

Pollutant:

Hexachlorocyclohexane (HCH), beta

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The BHC, beta criteria for the protection of human health from the consumption of water and organisms is 0.014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 79033, beta-BHC (Benzenehexachloride or beta-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127820

Pollutant:

Hexachlorocyclohexane (HCH), beta

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The BHC, beta criteria for the protection of human health from consumption of organisms only is 0.046 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 79033, beta-BHC (Benzenehexachloride or beta-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35169

Pollutant:

Hexachlorocyclohexane (HCH), beta

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The BHC, beta criteria for the protection of human health from consumption of organisms only is 0.046 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 79033, beta-BHC (Benzenehexachloride or beta-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79033, beta-BHC (Benzenehexachloride or beta-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79033, beta-BHC (Benzenehexachloride or beta-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 79033, beta-BHC (Benzenehexachloride or beta-HCH)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127821

Pollutant:

Hexachlorocyclohexane (HCH), beta

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The BHC, beta criteria for the protection of human health from the consumption of water and organisms is 0.014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70454	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	beta-Endosulfan (Endosulfan 2)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eleven lines of evidence are available in the administrative record to assess this pollutant.LOE No. 27211 is replaced by the LOE No. 46763 because LOE No. 27211 was reassessed using the upfated objective. None of the samples exceeded the objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of 10 total fraction water samples exceeded the CTR criteria. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70454, beta-Endosulfan (Endosulfan 2)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35040

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule criteria for beta-endosulfan to protect human health for waters that include the designated use of MUN is 110 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70454, beta-Endosulfan (Endosulfan 2)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35044

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan II criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for beta-endosulfan is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70454, beta-Endosulfan (Endosulfan 2)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127635

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan II criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for beta-endosulfan is 0.056 ug/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70454, beta-Endosulfan (Endosulfan 2)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127861

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule criteria for beta-endosulfan to protect human health for waters that include the designated use of MUN is 110 ug/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70454, beta-Endosulfan (Endosulfan 2)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35035

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan II criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70454, beta-Endosulfan (Endosulfan 2)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127633

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan II criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70454, beta-Endosulfan (Endosulfan 2)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127636

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan II criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for beta-endosulfan is 0.056 ug/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70454, beta-Endosulfan (Endosulfan 2)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7634

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70454, beta-Endosulfan (Endosulfan 2)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70454, beta-Endosulfan (Endosulfan 2)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70454, beta-Endosulfan (Endosulfan 2)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	69895	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	cis-1,2-Dichloroethylene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. LOEs 127759 and 127760 are duplicates. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of 6 total fraction samples exceeded the California drinking water MCL. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 69895, cis-1,2-Dichloroethylene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 69895, cis-1,2-Dichloroethylene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127759

Pollutant:

cis-1,2-Dichloroethylene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for cis-1,2-Dichloroethylene incorporated by reference in the Basin Plan is 0.006 mg/L (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 69895, cis-1,2-Dichloroethylene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127760

Pollutant:

cis-1,2-Dichloroethylene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Dichloroethylene, cis 1,2- is 0.006 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 69895, cis-1,2-Dichloroethylene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35237

Pollutant:

cis-1,2-Dichloroethylene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Dichloroethylene, cis 1,2- is 6 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	78511	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	m-Dichlorobenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27211 is replaced by the LOE No. 46763. None of samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the CTR criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 78511, m-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34752

Pollutant:

1, 3 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 3-Dichlorobenzene criteria for the protection of human health from consumption of organisms only is 2,600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78511, m-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127096

Pollutant:

1, 3 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 3-Dichlorobenzene criteria for the protection of human health from consumption of organisms only is 2,600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78511, m-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127490

Pollutant:

1, 3 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 3-Dichlorobenzene criteria for the protection of human health from the consumption of water and organisms is 400 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78511, m-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78511, m-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78511, m-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78511, m-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34768

Pollutant:

1, 3 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 3-Dichlorobenzene criteria for the protection of human health from the consumption of water and organisms is 400 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104425	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	n-Butylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of four total fraction samples exceeded the Division of Drinking Water Notification Level. Zero of 15 dissolved fraction water samples collected 2002-2004 exceeded the guideline as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104425, n-Butylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29486

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104425, n-Butylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127726

Pollutant:

n-Butylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104426	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	n-Propylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of four total fraction samples exceeded the Division of Drinking Water Notification Level. Zero of 15 dissolved fraction water samples collected 2002-2004 exceeded the guideline as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104426, n-Propylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29486

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 104426, n-Propylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126976

Pollutant:

n-Propylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	71287	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	o-Dichlorobenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. LOE No. 7652 is replaced by the LOE No. 7674 and LOE No. 27211 is replaced by the LOE No. 46763 because they were re-assessed using a different guideline. None of other samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the CTR criteria. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71287, o-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71287, o-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71287, o-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71287, o-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34762

Pollutant:

o-Dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 2-Dichlorobenzene is 600 ug/L (Title 22 of the California Code of Regulations ).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71287, o-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127881

Pollutant:

o-Dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichlorobenzene criteria for the protection of human health from consumption of organisms only is 17,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71287, o-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34746

Pollutant:

o-Dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichlorobenzene criteria for the protection of human health from consumption of organisms only is 17,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71287, o-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127882

Pollutant:

o-Dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 2-Dichlorobenzene is 0.6 mg/L (Title 22 of the California Code of Regulations ).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71287, o-Dichlorobenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	71610	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	p-Dichlorobenzene (DCB)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27211 is replaced by the LOE No. 46763. None of samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the CTR criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 71610, p-Dichlorobenzene (DCB)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71610, p-Dichlorobenzene (DCB)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71610, p-Dichlorobenzene (DCB)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34789

Pollutant:

1, 4 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 4-Dichlorobenzene is 5 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71610, p-Dichlorobenzene (DCB)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127495

Pollutant:

1, 4 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 4-Dichlorobenzene is 0.005 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71610, p-Dichlorobenzene (DCB)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34773

Pollutant:

1, 4 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 4-Dichlorobenzene criteria for the protection of human health from consumption of organisms only is 2,600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71610, p-Dichlorobenzene (DCB)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127494

Pollutant:

1, 4 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 4-Dichlorobenzene criteria for the protection of human health from consumption of organisms only is 2,600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 71610, p-Dichlorobenzene (DCB)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71610, p-Dichlorobenzene (DCB)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	69950	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	pH
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Ten lines of evidence are available in the administrative record to assess this pollutant. One of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of 25 water samples exceeded the Basin Plan objective This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 69950, pH	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126901

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Colorado River Basin Region's water quality objective for all surface waters states the following: Since the regional waters are somewhat alkaline, pH shall range from 6.0-9.0. Discharges shall not cause any changes in pH detrimental to beneficial water uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 69950, pH	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32364

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 5 samples were outside the pH range specified in the water quality objective.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: Since the regional waters are somewhat alkaline, pH shall range from 6.0-9.0 (CRBRWQCB, 2006).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at station 715CRIDG1 - Colorado River at Imperial Dam Grates.

Temporal Representation:

Data were collected during October 2005, May 2006 and 2007, October 2007, and April 2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 69950, pH	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128300

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 69950, pH	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7708

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen water quality measurements were taken at 6 locations along this segment of the Colorado River. Eight measurements could not be used in this assessment because of equipment failure or lack of proper documentation. The 9 acceptable measurements were collected from 5/2002 through 5/2005 at 1 location. Of these total measurements, none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: Since the regional waters are somewhat alkaline, pH shall range from 6.0-9.0 (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Measurements were collected from the following Colorado River locations: downstream of Parker Dam, from three small associated lakes on the River (Ferguson, Taylor and Squaw), upstream of Imperial Dam, and at the Imperial Dam grates.

Temporal Representation:

Seventeen water quality measurements were collected. Water quality measurements were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Imperial Dam grate location. Measurements were usually collected in May and October. The rest of the locations were measured in May and October 2002. An extra measurement was collected from the upstream of Imperial Dam location in April 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 69950, pH	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128301

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 69950, pH	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128297

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 69950, pH	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128299

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 69950, pH	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128296

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 69950, pH	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127579

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 69950, pH	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126926

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Aquaculture

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104424	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	sec-Butylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of four total fraction samples exceeded the Division of Drinking Water Notification Level. Zero of 15 dissolved fraction water samples collected 2002-2004 exceeded the guideline as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104424, sec-Butylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127727

Pollutant:

sec-Butylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104424, sec-Butylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29486

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104421	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	tert-Butylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective(s). Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of four total fraction samples exceeded the Division of Drinking Water Notification Level. Zero of 15 dissolved fraction water samples collected 2002-2004 exceeded the guideline as no evaluation guideline for the dissolved fraction for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 104421, tert-Butylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127728

Pollutant:

tert-Butylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 104421, tert-Butylbenzene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29486

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70508	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	DDT (Dichlorodiphenyltrichloroethane)
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Sources:	Source Unknown
Expected TMDL Completion Date:	2031
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1, 3.5 and 3.6 of the Listing Policy. Under sections 3.1 and 3.5 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Twenty-one lines of evidence are available in the administrative record to assess this pollutant. Two out of six Total DDT fish fillet fish tissue samples exceed the modified OEHHA Fish Contaminant Goal of 15 ppb for the "Commercial or Recreational Collection of Fish, Shellfish, or Organisms" beneficial use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Tissue: Two out of six Total DDT fish fillet fish tissue samples exceed the modified OEHHA Fish Contaminant Goal of 15 ppb for the "Commercial or Recreational Collection of Fish, Shellfish, or Organisms" beneficial use. Sediment: Zero of seven DDT sediment samples exceed the probable effect concentration for Sum DDT of 62.9 ug/kg. (dw = Dry Weight) for the "Warm Freshwater Habitat" beneficial use. LOE 32959 was re-assessed using this guideline. Zero of three Total DDT sediment samples exceed the probable effect concentration for Total DDTs of 572 ug/kg. (dw = Dry Weight) for the "Warm Freshwater Habitat" beneficial use. Water: Zero of 4 total fraction water samples exceeded the California Toxics Rule (CTR) DDT(p,p) criteria for the protection of human health from the consumption of water and organisms of 0.00059 ug/L (CTR, 2000). for the "Municipal & Domestic Supply" beneficial use. Zero of 17 dissolved fraction water samples exceeded the California Toxics Rule (CTR) Criterion Maximum Concentration (CMC) for p,p'-DDT of 1.1 ug/l for the protection of freshwater aquatic life uses (USEPA, 2000) for the "Warm Freshwater Habitat" beneficial use. Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) fish fillet fish tissue samples exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128422

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criteria for the protection of human health from consumption of organisms only is 0.00059 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125531

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125769

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126421

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total DDT concentration of 1000 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46006

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT, Total. One composite (6 fish per composite) were generated from one species: Largemouth Bass. Total DDT was calculated as the sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126197

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126424

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for total DDT in fish tissue is 15 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126198

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and the results are as follows 2 of the 5 samples exceeded the water quality standard for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 4 fish species (1 composite(s) of Flathead Catfish each composed of 5 fish per composite, 1 composite(s) of Channel Catfish each composed of 2 fish per composite, 1 composite(s) of Common Carp each composed of 5 fish per composite, 1 composite(s) of Striped Bass each composed of 5 fish per composite). Of these, 2 species (Channel Catfish, Common Carp) exceeded the water quality standard.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46005

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT, Total. One composite (6 fish per composite) were generated from one species: Largemouth Bass. Total DDT was calculated as the sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126315

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRSQLK.

Temporal Representation:

Data for this line of evidence were collected between 2014-10-07 and 2014-10-28

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7643

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criterion Maximum Concentration (CMC) for pp'-DDT of 1.1 ug/l for the protection of freshwater aquatic life uses (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125737

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32959

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 4 samples collected for Total DDTs exceeded the evaluation guideline.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Probable Effect Concentration for Total DDTs (DDD + DDE + DDT) in freshwater sediments is 572 ug/kg.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following station: Colorado River at Imperial Dam Grates - 715CRIDG1.

Temporal Representation:

The samples were collected on 10/25/2005 - 4/22/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32953

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 4 samples collected for Sum DDT exceeded the evaluation guideline.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Probable Effect Concentration for Sum DDT (o,p' + p,p') in freshwater sediments is 62.9 ug/kg.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following station: Colorado River at Imperial Dam Grates - 715CRIDG1.

Temporal Representation:

The samples were collected on 10/25/2005 - 4/22/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125682

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 (Station Codes: 715CRIDG1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-05 to 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34529

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The detection limit for DDT(o,p) is 0.001 ug/l, and the reporting limit for that is 0.002 ug/l. Since the WQS is smaller than the reporting limit, none of samples can be counted. In addition the detection limit for DDT(p,p') is 0.002 ug/l and the reporting limit is 0.005 ug/l, none of the samples can be counted. The water body was assessed for the sum of DDT(o,p') and DDT(p,p').

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 4,4' DDT criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at stations 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128419

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34546

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The method detection limit for all 6 of the non-detect samples was greater than the criteria: thus the data was not used in this assessment.

Data Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 4,4' DDT criterion for the protection of human health from the consumption of water and organisms is 0.00022 ug/L (USEPA Nationally Recommended Criteria, 2006).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at stations 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128420

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The DDT(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128421

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70508, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126423

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Sportfish Rivers and Streams.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 715CRBLYT.

Temporal Representation:

Data for this line of evidence were collected between 2011-05-10 and 2011-05-10

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	104423	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Sodium
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	Source Unknown
Expected TMDL Completion Date:	2031
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2, a single line(s) of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Thirty-nine of the 39 samples exceed the health advisory (for individuals on a sodium-restricted diet) of 20 mg/l (Drinking Water Standards and Health Advisories, USEPA 2012). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3.Thirty-nine of the 39 samples exceed the health advisory (for individuals on a sodium-restricted diet) of 20 mg/l (Drinking Water Standards and Health Advisories, USEPA 2012). This exceeds the allowable frequency of the Listing Policy in Table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

Line of Evidence (LOE) for Decision ID 104423, Sodium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125975

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 39 of 39 samples exceeded the water quality standard for Sodium.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the sodium threshold of 69 mg/L, agricultural uses of water should not be limited.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2017-03-10

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 104423, Sodium	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126127

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 39 of 39 samples exceeded the water quality standard for Sodium.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Per the Drinking Water Standards and Health Advisories (USEPA 2012), the health advisory for sodium for individuals on a sodium-restricted diet is 20 mg/l.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2017-03-10

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.


DECISION ID	70202	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Specific Conductance
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Sources:	Source Unknown
Expected TMDL Completion Date:	2031
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Ten of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 17 dissolved fraction water samples collected 2002-2005 exceeded the drinking water secondary MCL of 1600 uS/cm. Zero of five "none" fraction water samples collected 2005-2008 exceeded the drinking water secondary MCL of 1600 uS/cm. Ten of 11 total fraction water samples collected 2010-2013 exceeded the drinking water secondary MCL of 900 uS/cm. Total fraction water samples exceed the allowable frequency in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

Line of Evidence (LOE) for Decision ID 70202, Specific Conductance	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35274

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The California Secondary MCL for specific conductance is 1600 uS/cm (Title 22 California Code of Regulations).

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR title 22 section 64449.

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-4/22/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 70202, Specific Conductance	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127002

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70202, Specific Conductance	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7682

Pollutant:

Specific Conductance

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen measurements were generally collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total measurements, none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 1600 umhos for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Temporal Representation:

Seventeen water quality measurements were collected. Water quality measurements were generally collected biannually from 5/2002 through 5/2005 from the Imperial Dam grate location. Measurements were usually collected in May and October. The rest of the locations were measured in May and October 2002. An extra measurement was collected from the upstream of Imperial Dam location in April 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	104158	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Total Dissolved Solids
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	Source Unknown
Expected TMDL Completion Date:	2031
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. 50 of the samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Fifty of 50 water samples exceeded the California Secondary Maximum Contaminant Levels and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

Line of Evidence (LOE) for Decision ID 104158, Total Dissolved Solids	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

125955

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 39 of 39 samples exceeded the water quality standard for Total Dissolved Solids.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

California Secondary Maximum Contaminant Levels (MCLs) for consumer acceptance objective for total dissolved solids is 500 mg/L.

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2017-03-10

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 104158, Total Dissolved Solids	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127535

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

California Secondary Maximum Contaminant Levels (MCLs) for consumer acceptance objective for total dissolved solids is 500 mg/L.

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	70281	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Turbidity
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Sources:	Source Unknown
Expected TMDL Completion Date:	2031
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Twelve of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Ten of 31 total fraction and two of 17 dissolved fraction water samples exceeded the drinking water secondary MCL, This does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

Line of Evidence (LOE) for Decision ID 70281, Turbidity	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128012

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Aesthetic Qualities. All waters shall be free from substances attributable to wastewater of domestic or industrial origin or other discharges which adversely affect beneficial uses not limited to: Producing objectionable color, odor, taste, or turbidity. (Water Quality Control Plan, Colorado River Basin Region).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Maximum Contaminant Levels (MCLs) apply to ambient surface waters under the Basin Plan's narrative objective for Aesthetic Qualities. The Secondary MCL for turbidity is 5 nephelometric turbidity units (NTU). (Cal. Code Regs., tit. 22, § 64449.)

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 4 monitoring site(s) (715CRIDG1, 715CRIDU1, 715CRPDDM, 715CRSQLK)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70281, Turbidity	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7606

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen water quality measurements were collected biannually from 5/2002 through 5/2005 at 6 locations along this segment of the Colorado River. Of these total measurements, two exceeded the CDPH SMCL . The exceedances were found in measurements collected on 4/09/2003 upstream of Imperial Dam, and 5/10/2005 at Imperial Dam grates (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 5 NTU for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Temporal Representation:

Seventeen water quality measurements were collected. Water quality measurements were generally collected biannually from 5/2002 through 5/2005 from the Imperial Dam grate locations. Measurements were usually collected in May and October. The rest of the locations were measured in May and October 2002. An extra measurement was collected from the upstream of Imperial Dam location inn April 2003 The exceedances were found in measurements collected from 4/09/2003 through 5/10/2005.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70281, Turbidity	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126034

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 7 of 20 samples exceeded the water quality standard for Turbidity.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-29 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.


DECISION ID	77061	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,1,1,2-Tetrachloroethane \| 1,1-Dichloropropene \| 1,2,3-Trichloropropane \| 1,2-Dibromo-3-chloropropane \| 1,2-Dibromo-3-chloropropane (DBCP) \| 1,3-Dichloropropane \| 2,2-Dichloropropane \| Bromochloromethane \| Chloroform \| Ethylene dibromide \| Methylene bromide (Dibromomethane)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29489 received a use rating of insufficient because no evalution guideline for these pollutants were available in last assessment. However, evaluation guidelines for Chloroform and 1,2-Dibromo-3-chloropropane (DBCP) are avaialble in current assessment cycle, and none of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Two water samples were collected for 1,2-Dibromo-3-chloropropane (DBCP), but the results were not used in the assessment because the laboratory data reporting limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy. 4. None of two water samples exceeded the California MCL for chloroform and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77061, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35002

Pollutant:

Chloroform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for total trihalomethanes is 80 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 77061, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34998

Pollutant:

Chloroform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Chloroform criteria for the protection of human health from consumption of organisms only is 470 ug/L (The National Recommended Water Quality Criteria 2009).

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 77061, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29489

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 77061, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34727

Pollutant:

1,2-Dibromo-3-chloropropane (DBCP)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 2-Dibromo-3-Chloropropane(DBCP) is 0.20 ug/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76947	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,2,3-Trichlorobenzene \| Chloroethane \| Dichlorodifluoromethane \| Methyl chloride (Chloromethane) \| cis-1,3-Dichloropropene \| trans-1,3-Dichloropropene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Methyl Chloride, Chloroethane, Dichlorodifluoromethane, cis-1,3-Dichloropropene, trans-1,3-Dichloropropene, and 1,2,3-Trichlorobenzene consistent with Listing Policy section 3.1. No evaluation guidelines for the dissolved fractions of Methyl Chloride, Chloroethane, Dichlorodifluoromethane, cis-1,3-Dichloropropene, trans-1,3-Dichloropropene, or 1,2,3-Trichlorobenzene for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved fractions of Methyl Chloride, Chloroethane, Dichlorodifluoromethane, cis-1,3-Dichloropropene, trans-1,3-Dichloropropene, 1,2,3-Trichlorobenzene for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76947, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29810

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Six water samples were collected in 5/2002 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Methyl Chloride, Chloroethane, Dichlorodifluoromethane, cis-1,3-Dichloropropene, trans-1,3-Dichloropropene, or 1,2,3-Trichlorobenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Six water samples were collected. Water samples were collected in 5/2002 from the six locations.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	77020	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,2,4-Trimethylbenzene \| 1,3,5-Trimethylbenzene \| Bromobenzene \| Cumene \| delta-BHC (Benzenehexachloride or delta-HCH) \| n-Butylbenzene \| n-Propylbenzene \| sec-Butylbenzene \| tert-Butylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, and tert-Butylbenzene consistent with Listing Policy section 3.1. No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene or the sediment fraction of delta-BHC for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene or the sediment fraction of delta-BHC for the protection of human, animal or aquatic life in fresh waters that meets the requirements of section 6.1.3 of the Listing Policy could be found. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77020, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29544

Pollutant:

delta-BHC (Benzenehexachloride or delta-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Nine sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guideline for the sediment fraction of delta-BHC for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Nine sediment samples were collected. Sediment samples were collected and analyzed in May of 2002, November of 2003, and May of 2004 from the Imperial Dam grate location. The rest of the locations were sampled in May of 2002. An extra sample was collected from the upstream of Imperial Dam location in April 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 77020, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29486

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70207	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1,2-Dichloropropane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. LOEs No. 27212 and 7674 are replaced by the LOEs No. 46761 and 7649, respectively, because the objectives were updated. None of samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and none of six total fraction water samples exceeded the CTR criteria for the "Commercial or recreational collection of fish, shellfish, or organisms" beneficial use assessed. None of 11 dissolved fraction and none of two total fraction water samples exceeded the CTR criteria for the " Municipal & Domestic Supply" beneficial use assessed. Ten samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 70207, 1,2-Dichloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7649

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70207, 1,2-Dichloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

128950

Pollutant:

1,2-Dichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichloropropane, 1,2-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloropropane criteria for the protection of human health from the consumption of water and organisms is 0.52 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 2 station(s) (Station Code(s) 715CRIDG1, 715CRPDDM).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-04-15 to 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70207, 1,2-Dichloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34814

Pollutant:

1,2-Dichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloropropane criteria for the protection of human health from the consumption of water and organisms is 0.52 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70207, 1,2-Dichloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127767

Pollutant:

1,2-Dichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloropropane criteria for the protection of human health from consumption of organisms only is 39 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2013-04-15 and 2013-11-19

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 70207, 1,2-Dichloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34799

Pollutant:

1,2-Dichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloropropane criteria for the protection of human health from consumption of organisms only is 39 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70207, 1,2-Dichloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46761

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen samples were taken at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70207, 1,2-Dichloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70207, 1,2-Dichloropropane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27212

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	77101	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1-Methylnaphthalene \| 2,3,5-Trimethylnaphthalene \| 2,6-Dimethylnaphthalene \| 2-Methylnaphthalene \| Acenaphthylene \| Naphthalene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess Acenaphthylene, Naphthalene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, and 2,3,5-Trimethylnaphthalene consistent with Listing Policy sections 3.1 and 3.6. No evaluation guidelines for the dissolved fractions of Acenaphthylene, Naphthalene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene or the sediment fractions of Acenaphthylene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved fractions of Acenaphthylene, Naphthalene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene or the sediment fraxctions of Acenaphthylene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77101, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29492

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Acenaphthylene, Naphthalene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 77101, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29547

Pollutant:

1-Methylnaphthalene | 2,3,5-Trimethylnaphthalene | 2,6-Dimethylnaphthalene | 2-Methylnaphthalene | Acenaphthylene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76908	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	1-Methylphenanthrene \| Phenanthrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess Phenanthrene, and 1-Methylphenanthrene consistent with Listing Policy sections 3.1 and 3.6. No evaluation guidelines for the dissolved fractions of Phenanthrene, or 1-Methylphenanthrene or the sediment fraction of 1-Methylphenanthrene for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved fractions of Phenanthrene, or 1-Methylphenanthrene or the sediment fraction of 1-Methylphenanthrene for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76908, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29491

Pollutant:

1-Methylphenanthrene | Phenanthrene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Phenanthrene, or 1-Methylphenanthrene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76908, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29546

Pollutant:

1-Methylphenanthrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guideline for the sediment fraction of 1-Methylphenanthrene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	77021	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	2-Chlorotoluene \| 4-Chlorotoluene \| p-Cymene (p-Isopropyltoluene)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess 2-Chlorotoluene, 4-Chlorotoluene, and p-Cymene consistent with Listing Policy section 3.1. No evaluation guidelines for the dissolved fractions of 2-Chlorotoluene, 4-Chlorotoluene, p-Cymene for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved fractions of 2-Chlorotoluene, 4-Chlorotoluene, or p-Cymene for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77021, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29487

Pollutant:

2-Chlorotoluene | 4-Chlorotoluene | p-Cymene (p-Isopropyltoluene)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of 2-Chlorotoluene, 4-Chlorotoluene, or p-Cymene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76948	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	2-Hexanone \| Acetone \| Methyl ethyl ketone (2-Butanone) \| Methyl isobutyl ketone (Methyl-2-Pentanone)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Acetone, Methyl Isobutyl Ketone, Methyl Ethyl Ketone, and 2-Hexanone consistent with Listing Policy section 3.1. No evaluation guidelines for the dissolved fractions of Acetone, Methyl Isobutyl Ketone, Methyl Ethyl Ketone, or 2-Hexanone for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved fractions of Acetone, Methyl Isobutyl Ketone, Methyl Ethyl Ketone, or 2-Hexanone for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76948, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29507

Pollutant:

2-Hexanone | Acetone | Methyl ethyl ketone (2-Butanone) | Methyl isobutyl ketone (Methyl-2-Pentanone)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Six water samples were collected in 5/2002 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Acetone, Methyl Isobutyl Ketone, Methyl Ethyl Ketone, or 2-Hexanone for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Six water samples were collected. Water samples were collected in 5/2002 from the six locations.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	78577	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Acenaphthene \| Aldrin \| Chlorpyrifos \| Diazinon \| Toxaphene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Acenaphthene, Aldrin, Chlorpyrifos, Diazinon, and Toxaphene consistent with Listing Policy section 3.6. No evaluation guidelines for the sediment fractions of Acenaphthene, Aldrin, Chlorpyrifos, Diazinon, or Toxaphene for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the sediment fractions of Acenaphthene, Aldrin, Chlorpyrifos, Diazinon, or Toxaphene for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 78577, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29596

Pollutant:

Acenaphthene | Aldrin | Chlorpyrifos | Diazinon | Toxaphene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of alpha-HCH, beta-HCH, Hexachlorobenzene, or Methoxychlor for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76614	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Aluminum \| Manganese \| Silver
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess Aluminum, Manganese, and Silver consistent with Listing Policy section 3.6. No evaluation guidelines for the sediment fractions of Aluminum, Manganese, or Silver for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the sediment fractions of Aluminum, Manganese, or Silver for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76614, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29594

Pollutant:

Aluminum | Manganese | Silver

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Aluminum, Manganese, or Silver for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76382	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Ametryn \| Prometryn \| Simetryn \| Terbutryn
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	These pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29501 received a use rating of insufficient in laste assessemtn cycle because no evaluation guideline were available for these pollutants. However, an evaluation guideline for prometryn is available, and none of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of six water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Prometryn and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76382, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29501

Pollutant:

Ametryn | Prometryn | Simetryn | Terbutryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fourteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ametryn, Prometryn, Simetryn, or Terbutryn for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76382, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35540

Pollutant:

Prometryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Prometryn is 1 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):


DECISION ID	77808	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Anthracene \| Benzo(a)anthracene \| Dibenz[a,h]anthracene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29575 received a use rating of insufficient in last assessment cycle because no evaluation guideline were avaialble for these pollutants. However, an evaluation guideline for Anthracene in current assessment cycle, and none of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of four sediment samples exceeded the sediment quality guideline for anthracene and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77808, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29579

Pollutant:

Anthracene | Benzo(a)anthracene | Dibenz[a,h]anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Anthracene, Benz(a)Anthracene, or Dibenzo(a,h)Anthracene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 77808, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

32801

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of the 4 samples collected for Anthracene (sum of c0-c4) exceed the evaluation guideline.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Probable Effect Concentration for anthracene in freshwater sediments is 845 ug/kg.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following stations: Colorado River at Imperial Dam Grates (715CRIDG1).

Temporal Representation:

The samples were collected on 10/25/2005-4/21/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	77807	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Atroton \| Prometon (Prometone) \| Secbumeton
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29502 received a use rating of insufficient in last assessment cycle because no evaluation guideline were available for these pollutants. However, an evaluation guideline was available for prometon in current assessment cycle, and none of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of six water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Prometon and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77807, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35689

Pollutant:

Prometon (Prometone)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Prometon is 98 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 77807, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29502

Pollutant:

Atroton | Prometon (Prometone) | Secbumeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fourteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Atroton, Prometon, or Secbumeton for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76916	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Azinphos, Ethyl (Ethyl Guthion) \| Azinphos-methyl (Guthion)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29495 received a use rating of insufficient in last assessment cycle because no evaluation guideline were avaiable for these pollutants. However, an evaluation guideline for Azinphos-methyl (Guthion) is available, and none of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Six water samples were collected for Azinphos Methyl (Guthion), but the results were not used in the assessment because the laboratory data reporting limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy. This sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76916, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29495

Pollutant:

Azinphos, Ethyl (Ethyl Guthion) | Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Azinphos, methyl, or Azinphos, ethyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76916, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35308

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	76381	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Benzo(e)Pyrene (4,5-benzopyrene) \| Benzo[g,h,i]perylene \| Biphenyl \| Terbufos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess Benzo(g,h,i)Perylene, Benzo(e)Pyrene, Biphenyl, and Terbufos consistent with Listing Policy section 3.1. No evaluation guidelines for the dissolved fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, Biphenyl, or Terbufos or the sediment fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, or Biphenyl for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, Biphenyl, or Terbufos or the sediment fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, or Biphenyl for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76381, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29500

Pollutant:

Benzo(e)Pyrene (4,5-benzopyrene) | Benzo[g,h,i]perylene | Biphenyl | Terbufos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, Biphenyl, or Terbufos for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76381, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29576

Pollutant:

Benzo(e)Pyrene (4,5-benzopyrene) | Benzo[g,h,i]perylene | Biphenyl

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, or Biphenyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	77189	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Benzo[b]fluoranthene \| Benzo[k]fluoranthene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Benzo(b)Fluoranthene, and Benzo(k)Fluoranthene consistent with Listing Policy section 3.6. No evaluation guidelines for the sediment fractions of Benzo(b)Fluoranthene, or Benzo(k)Fluoranthene for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the sediment fractions of Benzo(b)Fluoranthene, or Benzo(k)Fluoranthene for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77189, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29580

Pollutant:

Benzo[b]fluoranthene | Benzo[k]fluoranthene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Benzo(b)Fluoranthene, or Benzo(k)Fluoranthene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76978	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Bolstar \| Chlordane \| Ciodrin \| Dacthal \| Demeton s \| Dichlorvos \| Dimethoate \| Disulfoton \| Endrin Ketone \| Ethoprop \| Famphur \| Mirex \| Naled \| Oxadiazon
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	These pollutant is being considered for placement on the section 303(d) list under section 3.1 and 3.5 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. LOE Nos. 29809 and 29574 received a use rating of insufficient in last assessment cycle because no evaluation guidelines were available. However guidelines for Dacthal and Dimethoate are available in current assessment cycle, and none of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of six water samples exceeded theUSEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50 for Dacthal, and none of 6 water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50 for Dimethoate. These sample size are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76978, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29574

Pollutant:

Dacthal | Mirex | Oxadiazon

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Dacthal, Mirex, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76978, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35010

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50 for Dimethoate is 43 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76978, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29809

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76978, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35343

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The National Recommended Water Quality Criteria for dacthal (DCPA) for the consumption of water and fish is 0.008 ug/L.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 76978, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35005

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50 for Dacthal 6600 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):


DECISION ID	77973	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Boron
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 39 total fraction, zero of six "none" fraction, and zero of two dissolved fraction water samples exceeded the California State Notification level.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 77973, Boron	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33648

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 6 samples exceeded the California State Notification Level criterion.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain concentrations of chemical constituents shall be present in amounts that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

The California State Notification Level criterion for boron is 1 mg/L.

Guideline Reference:

Drinking Water Notification Levels and Response Levels

Spatial Representation:

Data was collected at the following station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples were collected on 10/25/2005, 5/3/2006, 5/8/2007, 10/23/2007, 4/22/2008 and 10/29/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 77973, Boron	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127277

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Drinking water notification levels are published by the Division of Drinking Water. Notification levels are for chemicals for which there is no drinking water MCL. If a notification level is exceeded, local government notification is required and customer notification is recommended. The notification level for Boron is 1 mg/L.

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2010-10-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 77973, Boron	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127274

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The guideline for boron is 700 ug/L (0.7 mg/L).

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 77973, Boron	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127276

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2011-05-10 and 2011-10-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 77973, Boron	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126016

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 77973, Boron	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127278

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The guideline for boron is 700 ug/L (0.7 mg/L).

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site(s) (715CRIDG1)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2010-10-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 77973, Boron	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

126104

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The guideline for boron is 700 ug/L (0.7 mg/L).

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 2 monitoring site(s) (USGS-09427520, USGS-09429490)

Temporal Representation:

The samples were collected between the dates of 2010-11-23 and 2016-06-22

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.


DECISION ID	77303	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Carbon (organic)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess organic Carbon consistent with Listing Policy section 3.6. No evaluation guideline for the sediment fraction of organic carbon for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guideline for the sediment fraction of organic Carbon for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77303, Carbon (organic)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29598

Pollutant:

Carbon (organic)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guideline for the sediment fraction of Organic Carbon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76319	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Carbophenothion \| Dichlofenthion \| Dioxathion \| Ethion \| Fenitrothion \| Fensulfothion \| Fenthion \| Malathion \| Methidathion \| Methyl Parathion \| Parathion \| Tokuthion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	These pollutants are being considered for placement on the section 303(d) list under section 3.1 and 3.5 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess these pollutants. LOE Nos. 29493 and 29572 received a use rating of insufficient in last assessment cycle because no evaluation guideline were available for these pollutants. However, evaluation guidelines for some pollutants are available in current assessment cycle, and none of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Six water samples were collected for each Malathion and Parathion, but the results were not used in the assessment because the laboratory data reporting limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy. 4. None of six water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life MATC for Methidathion and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76319, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35361

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life MATC for Methidathion is 0.86 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76319, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35608

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The UC Davis Criteria for Malathion for the protection of aquatic organisms is a 4 day average of 0.028 ug/L.

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 76319, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29493

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76319, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29572

Pollutant:

Methyl Parathion | Parathion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Parathion, or Methyl Parathion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76319, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35557

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The criterion continuous concentration for Parathion, Ethyl is 0.013 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	76943	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Chlorfenvinphos \| Chlorpyrifos, methyl \| Cuomaphos \| Dicrotophos \| Dyfonate (Fonofos or Fonophos) \| Fenchlorphos \| Leptophos \| Merphos \| Mevinphos \| Tetrachlorvinphos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, and Chlorpyrifos Methyl consistent with Listing Policy section 3.1. No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76943, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29496

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos, Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76800	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Dibenzothiophene \| o-Xylene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess Dibenzothiophene, and o-Xylene consistent with Listing Policy sections 3.1 and 3.6. No evaluation guidelines for the dissolved fractions of Dibenzothiophene, or o-Xylene or the sediment fraction of Dibenzothiophene for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved fractions of Dibenzothiophene, or o-Xylene or the sediment fraction of Dibenzothiophene for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76800, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29578

Pollutant:

Dibenzothiophene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guideline for the sediment fraction of Dibenzothiophene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76800, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29506

Pollutant:

Dibenzothiophene | o-Xylene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Nine water samples were generally collected biannually from 10/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guideline for the dissolved fractions of Dibenzothiophene, or o-Xylene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Nine water samples were collected. Water samples were generally collected and analyzed from 10/2002 through 5/2004 from the upstream of the Imperial Dam, and at the Imperial Dam Grates locations. Samples were usually collected in May and October. Samples were not collected in 5/2003 from the Imperial Dam grates, samples were not collected from upstream of the Imperial Dam in 11/2003 and 5/2004. The rest of the locations were only sampled in 10/2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	77096	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Dichlorobenzophenone \| Indeno[1,2,3-cd]pyrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Indeno(1,2,3,c,d)Pyrene, and pp-DCBPconsistent with Listing Policy section 3.6. No evaluation guidelines for the sediment fractions of Indeno(1,2,3,c,d)Pyrene, or pp-DCBP for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the sediment fractions of Indeno(1,2,3,c,d)Pyrene, or pp-DCBP for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77096, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29597

Pollutant:

Dichlorobenzophenone | Indeno[1,2,3-cd]pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Indeno(1,2,3,c,d)Pyrene, or Dichlorobenzophenone (pp-DCBP) for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	71426	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Dichlorobromomethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27212 is replaced by the LOE No. 46761 because LOE No. 27212 and 7649 were assessed using the same water quality objective for two different beneficial uses in last assessment cycle. Although total of seventeen samples were collected, LOE No. 27212 had a total sample size of eleven due to the higher reporting limit than the objective. Because of wrong objective application in the last assessment, the number of the total sample discrepancy had occurred between LOE No. 27212 and LOE No. 46761. Thus, LOE No. 27212 is not included in the final use rating. None of other samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 water samples exceeded the CTR criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 71426, Dichlorobromomethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35201

Pollutant:

Dichlorobromomethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Bromodichloromethane criteria is 0.56 ug/L for the protection of human health from consumption of water and organisms (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-5/3/2006.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71426, Dichlorobromomethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46761

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Seventeen samples were taken at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71426, Dichlorobromomethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7649

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71426, Dichlorobromomethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27212

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70624	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Dichloromethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle.However, use ratings of LOE Nos. 27213 and 7646 are changed from fully supporting to insufficient due to insufficient sample size required by the Listing Policy to determine if the water quality objectives are met. No new data were assessed in current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 6 water samples exceeded the California Toxics Rule criteria protecting human health when consuming water and organisms from these waters. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 70624, Dichloromethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7646

Pollutant:

Dichloromethane | Methyl bromide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Six water samples were collected in 5/2002 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria for the protection of human health when consuming water and organisms from aquatic systems were used for the following constituents: 48 ug/l Methyl Bromide, and 5 ug/l Dichloromethane (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Six water samples were collected. Water samples were collected in 5/2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70624, Dichloromethane	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27213

Pollutant:

Dichloromethane | Methyl bromide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Six water samples were collected in 5/2002 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Six water samples were collected. Water samples were collected in 5/2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	78631	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Endosulfan sulfate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. LOE No. 27211 is replaced by the LOE No. 46763. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 17 dissolved fraction and 10 total fraction water samples exceed the California Toxics Rule criteria. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 78631, Endosulfan sulfate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35052

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan Sulfate criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78631, Endosulfan sulfate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127287

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan Sulfate criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

Line of Evidence (LOE) for Decision ID 78631, Endosulfan sulfate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7652

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78631, Endosulfan sulfate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

46763

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78631, Endosulfan sulfate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27211

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 78631, Endosulfan sulfate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35056

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan Sulfate criteria for endosulfan sulfate to protect human health for waters that include the designated use of MUN is 110 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 78631, Endosulfan sulfate	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

127286

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endosulfan Sulfate criteria for endosulfan sulfate to protect human health for waters that include the designated use of MUN is 110 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (715CRIDG1, 715CRPDDM)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program


DECISION ID	76949	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Endosulfan sulfate \| alpha-Endosulfan (Endosulfan 1) \| beta-Endosulfan (Endosulfan 2)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Endosulfan 1, Endosulfan 2, and Endosulfan Sulfate consistent with Listing Policy section 3.6. No evaluation guidelines for the sediment fractions of Endosulfan 1, Endosulfan 2, or Endosulfan Sulfate for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the sediment fractions of Endosulfan 1, Endosulfan 2, or Endosulfan Sulfate for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76949, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29581

Pollutant:

Endosulfan sulfate | alpha-Endosulfan (Endosulfan 1) | beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Endosulfan 1, Endosulfan 2, or Endosulfan Sulfate for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70844	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Escherichia coli (E. coli)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 16 water samples exceeded the Basin Plan objective for water contact recreation and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 26 samples is needed for application of table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 70844, Escherichia coli (E. coli)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7701

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan:In the Colorado River the maximum allowable E. coli density is 235 MPN/ 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70844, Escherichia coli (E. coli)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33245

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

The one sample collected did not exceed the E. coli objective.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The E. coli concentration shall not exceed more than 235/100ml. Basin Plan for the Colorado River Basin.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The sample was collected from the Colorado River at Imperial Dam Grates station 715CRIDG1.

Temporal Representation:

The sample was collected in October 2005.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70844, Escherichia coli (E. coli)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7704

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan:In the Colorado River the maximum allowable E. coli density is 1175 MPN/ 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	77095	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Heptachlor \| Heptachlor epoxide
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Heptachlor, and Heptachlor Epoxide consistent with Listing Policy section 3.6. No evaluation guidelines for the sediment fractions of Heptachlor, or Heptachlor Epoxide for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the sediment fractions of Heptachlor, or Heptachlor Epoxide for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77095, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29582

Pollutant:

Heptachlor | Heptachlor epoxide

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of Heptachlor, or Heptachlor Epoxide for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	77190	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Hexachlorobenzene/ HCB \| Methoxychlor \| alpha.-BHC (Benzenehexachloride or alpha-HCH) \| beta-BHC (Benzenehexachloride or beta-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: These pollutants are being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess alpha-HCH, beta-HCH, Hexachlorobenzene, and Methoxychlor consistent with Listing Policy section 3.6. No evaluation guidelines for the sediment fractions of alpha-HCH, beta-HCH, Hexachlorobenzene, or Methoxychlor for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the sediment fractions of alpha-HCH, beta-HCH, Hexachlorobenzene, or Methoxychlor for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77190, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29595

Pollutant:

Hexachlorobenzene/ HCB | Methoxychlor | alpha.-BHC (Benzenehexachloride or alpha-HCH) | beta-BHC (Benzenehexachloride or beta-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions of alpha-HCH, beta-HCH, Hexachlorobenzene, or Methoxychlor for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76849	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Hydroxide
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Hydroxide consistent with Listing Policy section 3.1. No evaluation guidelines for the dissolved fraction of Hydroxide for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved fraction of Hydroxide for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76849, Hydroxide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29508

Pollutant:

Hydroxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Six water samples were collected in 5/2002 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guideline for Hydroxide for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Six water samples were collected. Water samples were collected in 5/2002 from the six locations.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70139	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Methyl bromide
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. However, a use rating of LOE Nos. 27213 and 7646 are changed from fully supporting to insufficient due to insufficient sample size required by the Listing Policy to determine if the water quality objectives are met. No new data were assessed in current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 6 water samples exceeded the California Toxics Rule criteria protecting human health when consuming water and organisms from these waters. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 70139, Methyl bromide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

27213

Pollutant:

Dichloromethane | Methyl bromide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Six water samples were collected in 5/2002 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Six water samples were collected. Water samples were collected in 5/2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70139, Methyl bromide	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7646

Pollutant:

Dichloromethane | Methyl bromide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Six water samples were collected in 5/2002 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Six water samples were collected. Water samples were collected in 5/2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	103893	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line(s) of evidence are necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of six samples exceed the California Maximum Contaminant Level. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3.Zero of six samples exceed the California Maximum Contaminant Level and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 103893, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35533

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Nitrate/Nitrite (Nitrite + Nitrate as N) is 10 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	76195	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Oxychlordane \| Perylene (Dibenz(de,kl)anthracene) \| Phorate \| Phosmet \| Phosphamidon \| Sulfotep \| Tedion \| Thionazin \| Trichlorfon \| Trichloronate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	These pollutants are being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess these pollutants. LOE Nos. 29499 and 29575 received use rating of insufficient in last assessment cycle because no evaluation guidelines were available. However, evaluation guidelines for Phorate and Phosmet are available in current assessment cycle, and none of the samples exceed the water quality objectives. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of six water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50 for Phorate, and none of six water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Phosmet . These sample size are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76195, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35664

Pollutant:

Phosmet

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Phosmet is 5.6 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76195, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29499

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76195, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29575

Pollutant:

Oxychlordane | Perylene (Dibenz(de,kl)anthracene) | Tedion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fifteen sediment samples were generally collected from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76195, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35621

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50 for Phorate is 2 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):


DECISION ID	77188	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Pheophytin a
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.7.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Pheophytin a consistent with Listing Policy section 3.7.1. No evaluation guideline for the dissolved fraction of Pheophytin a for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guideline for the dissolved fraction of Pheophytin a for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77188, Pheophytin a	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29509

Pollutant:

Pheophytin a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Six water samples were collected in 5/2002 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guideline for Pheophytin a for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Six water samples were collected. Water samples were collected in 5/2002 from the six locations.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76799	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Propazine \| Terbuthylazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	These pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess Propazine, and Terbuthylazine consistent with Listing Policy section 3.1. LOE No. 29503 received a use rating of insufficient information in last assessment cycle because no evaluation guidelines were available for these pollutants. However, an evaluation guideline for Propazine is available in current assessment cycle, and none of samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3.None of six water samples exceeded the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Propazine and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76799, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35581

Pollutant:

Propazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Propazine is 25 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76799, Multiple Pollutants	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29503

Pollutant:

Propazine | Terbuthylazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fourteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for the dissolved fractions of Propazine, or Terbuthylazine for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76286	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Salinity
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. LOE No. 29510 received a use rating of infufficient in last assessment cycle because no evalution guideline was available for this pollutnat. However, a water quality objective for salinity is available in current assessement cycle, and none of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of Five water samples exceeded the Basin Plan objective and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 26 samples is needed for application of table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76286, Salinity	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

34572

Pollutant:

Salinity/TDS/Chlorides

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

0 of the 5 samples were greater than the site specific objective.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Colorado River Basin Plan has a site specific numeric objective for stating: "The flow-weighted average annual numeric criteria for salinity (total dissolved solids) were established at three locations on the lower Colorado River: Imperial Dam, AZ-CA ...................879 mg/L."

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at stations 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

Samples collected between 10/25/2005 and 10/29/2008.

Environmental Conditions:

QAPP Information:

SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 76286, Salinity	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29510

Pollutant:

Salinity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Three water samples were collected from 4/2003 through 4/2004 at 2 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guideline for Salinity for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Colorado River locations: upstream of Imperial Dam, and at the Imperial Dam grates.

Temporal Representation:

Three water samples were collected. Water samples were collected from 4/2003 through 4/2004 upstream of the Imperial Dam, and 11/2003, and 5/2004 from the Imperial Dam Grates.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	80151	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Streptococcus, fecal
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.3 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess fecal Streptococcus consistent with Listing Policy section 3.3. No evaluation guidelines for the total density of fecal Streptococcus for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the total density of fecal Streptococcus for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 80151, Streptococcus, fecal	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29505

Pollutant:

Streptococcus, fecal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fourteen water samples were generally collected biannually from 5/2002 through 5/2004 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guideline for Streptococcus for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	71224	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Styrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. However, a use rating of LOE No. 7656 is changed from fully supporting to insufficient due to insufficient sample size required by the Listing Policy to determine if the water quality objectives are met. No new data were assessed in current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 6 water samples exceeded the drinking water MCL and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 71224, Styrene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7656

Pollutant:

Styrene | Trichlorofluoromethane (CFC-11)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Six water samples were collected in 5/2002 at 6 locations along this segment of the Colorado River. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.1 mg/l Styrene, and 0.15 mg/l Trichlorofluoromethane (CFC-11) (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Six water samples were collected. Water samples were collected in 5/2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	71488	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Thiobencarb/Bolero
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 23 water samples exceeded either the secondary drinking water MCL and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 71488, Thiobencarb/Bolero	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35387

Pollutant:

Thiobencarb/Bolero

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Evaluation Guideline:

The California Secondary MCL for thiobencarb is 0.001 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR title 22 section 64449.

Spatial Representation:

Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) was collected at 1 monitoring site [ Colorado River at Imperial Dam Grates]

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 71488, Thiobencarb/Bolero	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7679

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 71488, Thiobencarb/Bolero	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

35383

Pollutant:

Thiobencarb/Bolero

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life MATC for Thiobencarb is 1.4 ug/L.

Guideline Reference:

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Spatial Representation:

Temporal Representation:

Data was collected over the time period 10/25/2005-10/29/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 71488, Thiobencarb/Bolero	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

7674

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	76242	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Total Petroleum Hydrocarbons as Diesel
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess Total Petroleum Hydrocarbons as Diesel used to refer to the dissolved fractions of Diesel Range Organics consistent with Listing Policy sections 3.1 and 3.6. No evaluation guidelines for the dissolved or sediment fractions of Total Petroeum Hydrocarbons as Diesel for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved and sediment fractions of Total Petroleum Hydrocarbons as Diesel for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76242, Total Petroleum Hydrocarbons as Diesel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29577

Pollutant:

Total Petroleum Hydrocarbons as Diesel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Fourteen sediment samples were generally collected from 5/2002 through 11/2003 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines forthe sediment fractions Total Petroleum Hydrocarbons as Diesel, used to refer to the dissolved fractions of Diesel Range Organics (dro), for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Fourteen sediment samples were collected. Sediment samples were generally collected and analyzed biannually from 5/2002 through 11/2003 from the Imperial Dam grate location. Samples were usually collected in May and October from the Imperial Dam grate location. No sample was collected from the Imperial Dam grate location in April of 2003. The rest of the locations were sampled in May and October of 2002. An extra sample was collected from the upstream of Imperial Dam location in April of 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 76242, Total Petroleum Hydrocarbons as Diesel	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

29504

Pollutant:

Total Petroleum Hydrocarbons as Diesel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Thirteen water samples were generally collected biannually from 5/2002 through 4/2003 at 6 locations along this segment of the Colorado River (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for Total Petroleum Hydrocarbons as Diesel, used to refer to the dissolved fractions of Diesel Range Organics (dro), for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Thirteen water samples were collected. Water samples were generally collected and analyzed from May of 2002 through May of 2003 from the upstream of the Imperial Dam location. Samples were collected in May and October of 2002. An extra sample was collected from the upstream of Imperial Dam location in April of 2003.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	79531	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Total Trihalomethane (TTHM)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of two water samples exceeded the California MCLs and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 79531, Total Trihalomethane (TTHM)	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

33041

Pollutant:

Total Trihalomethane (TTHM)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 2 samples exceeded the guidelines.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.(Water Quality Control Plan for the Colorado River Basin, 2006). California primary Maximum Contaminant Levels (MCLs) apply to ambient waters under the (Water Quality Control Plan for the Santa Ana River Basin) "Chemical Constituents" objective. The primary MCL for Total Trihalomethanes is 0.080 mg/L (80 ug/L).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at station 715CRIDG1 (Colorado River at Imperial Dam Grates).

Temporal Representation:

The samples were collected on 10/25/2005, and 5/3/2006.

Environmental Conditions:

QAPP Information:

SWAMP (2002) procedure.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	77979	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

Pollutant:	Toxaphene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.5 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of one fish tissue samples exceeded the NAS fish tissue guideline and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 77979, Toxaphene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45956

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Toxaphene. One composite (6 fish per composite) were generated from one species: largemouth bass. One sample was not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for toxaphene in fish tissue is 4.3 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 12/7/2004.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2002) was followed.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 77979, Toxaphene	Region 7
Colorado River and Associated Lakes and Reservoirs (Lake Havasu Dam to Imperial Dam)

LOE ID:

45957

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference: