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

Supporting Information

Regional Board 7 - Colorado River Basin Region

Water Body Name: Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
Water Body ID: CAR7132000020080709122810
Water Body Type: River & Stream
 
DECISION ID
77981
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
Pollutant: Toxicity
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2025
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 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. Four 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 removing this water segment-pollutant combination from 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. Four of six water samples exhibit toxicity when compared to control samples and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 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 removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 77981, Toxicity
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 32173
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 3
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Five samples were collected to evaluate water toxicity. Three of the samples exhibited significant toxicity to Ceriodaphnia dubia reproduction. The toxicity test included survival and reproduction of Ceriodaphnia dubia and survial and biomass of Pimephales promelas. 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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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 4 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 713CRNVBD.
Temporal Representation: The samples were collected in October and April 2008, October 2005 and May 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 77981, Toxicity
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 125402
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SWAMP RWB7 Monitoring for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) 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 Survival, Ceriodaphnia dubia, for Young/female
Data 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 that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Colorado River 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 1 stations. Monitoring site(s): ( 713CRNVBD )
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04.
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 77981, Toxicity
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 31972
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 3
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Five samples were collected to evaluate water toxicity. Three of the samples exhibited significant toxicity to Ceriodaphnia dubia reproduction. The toxicity test included survival and reproduction of Ceriodaphnia dubia and survial and biomass of Pimephales promelas. 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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 713CRNVBD.
Temporal Representation: The samples were collected in October and April 2008, October 2005 and May 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): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 77981, Toxicity
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 125388
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SWAMP RWB7 Monitoring for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) 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 Survival, Ceriodaphnia dubia, for Young/female
Data 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 that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Colorado River 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 1 stations. Monitoring site(s): ( 713CRNVBD )
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04.
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
71046
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 section 3.1 and 3.5 of the Listing Policy. Under section 3.1 and 3.5 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.

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 the samples exceeded the objectives for each matrix, fraction and beneficial use combination.

Seven 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.

All sample sizes were less than 16.

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 table3.1.

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 71046, Aldrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7632
 
Pollutant: Aldrin | Arsenic | Chlordane | Chromium (total) | Dieldrin | Endrin | Heptachlor | Heptachlor epoxide | alpha-Endosulfan (Endosulfan 1) | beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (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: 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: 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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71046, Aldrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 34824
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Aldrin.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 71046, Aldrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128616
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Aldrin.
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 71046, Aldrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128910
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 1 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: 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: 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 to 2010-10-04
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 71046, Aldrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128909
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 1 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: 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: 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 to 2010-10-04
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 71046, Aldrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 34804
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 71046, Aldrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 34820
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 71046, Aldrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 45923
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Aldrin. One composite (6 fish per composite) were generated from one species: largemouth bass.
Data Reference: RWB7 Fish Tissue Study 2004
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 12/9/2004.
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 71046, Aldrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 45924
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Aldrin. One composite (6 fish per composite) were generated from one species: largemouth bass.
Data Reference: RWB7 Fish Tissue Study 2004
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 12/9/2004.
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 71046, Aldrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 34808
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Aldrin.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 71046, Aldrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127852
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Aldrin.
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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
102927
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 two 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 two 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 102927, Alkalinity as CaCO3
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127372
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Alkalinity as CaCO3.
Data 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 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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
70631
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 7 water samples exceeded the California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health.

None of 15 water samples exceeded the California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Levels (SMCLs)

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 70631, Aluminum
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7673
 
Pollutant: 1, 1-dichloroethane | 1,1,1-Trichloroethane | 1,1,2-Trichloroethane | 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride | 1,2,4-Trichlorobenzene | 1,2-Dichloroethylene,-trans | 1,2-Dichloropropane | Aluminum | Arsenic | Benzo(a)pyrene (3,4-Benzopyrene -7-d) | Cadmium | Chlordane | Chlorobenzene (mono) | Chromium (total) | Endrin | Ethylbenzene | Heptachlor | Heptachlor epoxide | Hexachlorobenzene/ HCB | Lindane/gamma Hexachlorocyclohexane (gamma-HCH) | Mercury | Methoxychlor | Methyl Tertiary-Butyl Ether (MTBE) | Molinate | Nickel | Nitrate | Nitrogen, Nitrite | PCBs (Polychlorinated biphenyls) | Selenium | Tetrachloroethylene/PCE | Thiobencarb/Bolero | Toluene | Trichloroethylene/TCE | Xylenes (total) (mixed) | cis-1,2-Dichloroethylene | o-Dichlorobenzene | p-Dichlorobenzene (DCB)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location 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 near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 70631, Aluminum
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128191
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Aluminum.
Data 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 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 70631, Aluminum
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35177
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Aluminum.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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 Colorado River Basin, with amendments adopted through June 2006
 
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 (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 70631, Aluminum
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7677
 
Pollutant: Aluminum | Chloride | Copper | Manganese | Methyl Tertiary-Butyl Ether (MTBE) | Silver | Sulfates | Thiobencarb/Bolero | Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the CDPH SMCL (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 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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management 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
102928
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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 one total fraction water samples exceeded the USEPA Health Advisory for lifetime exposure.

Zero of the four dissolved fraction water samples exceeded as no evaluation guidelines for the dissolved fractions could be found that met the requirements of Section 6.1.3 of 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 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 one total fraction water samples exceeded the USEPA Health Advisory for lifetime exposure.

Zero of the four dissolved fraction water samples exceeded as no evaluation guidelines for the dissolved fractions 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 102928, Ametryn
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128470
 
Pollutant: Ametryn
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ametryn.
Data 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) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 102928, Ametryn
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 29454
 
Pollutant: Ametryn | Prometryn | Simetryn
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances:
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Four water samples were collected from 5/2002 through 5/2004 at 1 location in the river (SWAMP, 2006).
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 2004.
 
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: Samples were collected near the California Nevada Border.
Temporal Representation: Four water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2004 from the Nevada Border. Samples were usually collected in May and October. A sample was not collected in 11/2003.
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
103042
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
Pollutant: Ammonia
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 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 samples exceed the water quality objectives.

Sample sizes for each matrix/fraction/beneficial use/objective combination were less than 16.

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 103042, Ammonia
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128507
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data 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) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2013-11-05 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 103042, Ammonia
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127063
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data 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) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2013-11-05 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 103042, Ammonia
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127041
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data 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) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 103042, Ammonia
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127052
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data 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) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 103042, Ammonia
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 34570
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 6 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 6 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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: 1999 Update of Ambient Water Quality Criteria for Ammonia
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Sample was collected at 713CRNVBD (Colorado River at Nevada State Line).
Temporal Representation: Samples collected between 10/24/2005 and 10/28/2008.
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 103042, Ammonia
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127030
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data 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) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 103042, Ammonia
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128518
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data 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) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2013-11-05 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
71098
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 section 3.1 and 3.5 of the Listing Policy. Under section 3.1 and 3.5 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.

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. Tissue Samples:

Zero of zero tissue samples exceeded the modified OEHHA Fish Contaminant Goal for arsenic in fish tissue of 3.4 ppb for the "Commercial or recreational collection of fish, shellfish, or organisms" beneficial use assessed. The 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.

Water Samples:

Zero of eight water samples exceeded the California Maximum Contaminant Level of 10 ug/L for the "Municipal & Domestic Supply" beneficial use assessed.

Zero of seven water samples exceeded the California Maximum Contaminant Levels of 50 ug/l for the "Municipal & Domestic Supply" beneficial use assessed.

Zero of eight water samples exceeded the dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic of 150 ug/L (California Toxics Rule, 2000) for the "Warm Freshwater Habitat" beneficial use assessed.

Zero of eight water samples exceeded the dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic of 150 ug/L (California Toxics Rule, 2000 for the "Cold Freshwater Habitat" beneficial use assessed.

Zero of seven water samples exceeded the United State Fish and Wildlife Service (USFWS) Biological Effect Criteria for the protection of aquatic life uses of 250 ug/l for the "Warm Freshwater Habitat" beneficial use assessed.

Zero of seven water samples exceeded the California Toxics Rule (CTR) Criterion Maximum Concentrations (CMCs) for the protection of freshwater aquatic life uses of 340 ug/L for the "Warm Freshwater Habitat" beneficial use assessed.

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 71098, Arsenic
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7683
 
Pollutant: Arsenic | Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the USFWS Biological Effect Criteria (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. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).
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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71098, Arsenic
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127067
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Arsenic.
Data 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 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 71098, Arsenic
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35180
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Arsenic.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Maximum Contaminant Levels for organic and inorganic chemicals. CCR
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 71098, Arsenic
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35179
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Arsenic.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 71098, Arsenic
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127069
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Arsenic.
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 71098, Arsenic
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7632
 
Pollutant: Aldrin | Arsenic | Chlordane | Chromium (total) | Dieldrin | Endrin | Heptachlor | Heptachlor epoxide | alpha-Endosulfan (Endosulfan 1) | beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (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: 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: 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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71098, Arsenic
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7673
 
Pollutant: 1, 1-dichloroethane | 1,1,1-Trichloroethane | 1,1,2-Trichloroethane | 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride | 1,2,4-Trichlorobenzene | 1,2-Dichloroethylene,-trans | 1,2-Dichloropropane | Aluminum | Arsenic | Benzo(a)pyrene (3,4-Benzopyrene -7-d) | Cadmium | Chlordane | Chlorobenzene (mono) | Chromium (total) | Endrin | Ethylbenzene | Heptachlor | Heptachlor epoxide | Hexachlorobenzene/ HCB | Lindane/gamma Hexachlorocyclohexane (gamma-HCH) | Mercury | Methoxychlor | Methyl Tertiary-Butyl Ether (MTBE) | Molinate | Nickel | Nitrate | Nitrogen, Nitrite | PCBs (Polychlorinated biphenyls) | Selenium | Tetrachloroethylene/PCE | Thiobencarb/Bolero | Toluene | Trichloroethylene/TCE | Xylenes (total) (mixed) | cis-1,2-Dichloroethylene | o-Dichlorobenzene | p-Dichlorobenzene (DCB)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location 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 near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71098, Arsenic
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127068
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Arsenic.
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 71098, Arsenic
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 45925
 
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: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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) was 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: RWB7 Fish Tissue Study 2004
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 12/9/2004.
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 71098, Arsenic
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35222
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Arsenic.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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
69957
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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.

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 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 water samples exceeded the objectives. Sample sizes were less that 16 for each matrix/fraction/beneficial use/objective combination.

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 69957, Atrazine
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127265
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Atrazine.
Data 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: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 69957, Atrazine
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35264
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Atrazine.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Atrazine is 43 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 69957, Atrazine
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35244
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Atrazine.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Maximum Contaminant Levels for organic and inorganic chemicals. CCR
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 69957, Atrazine
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127267
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Atrazine.
Data 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: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 69957, Atrazine
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35265
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Atrazine.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Atrazine is 43 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 69957, Atrazine
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127268
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Atrazine.
Data 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) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 69957, Atrazine
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7670
 
Pollutant: Atrazine | Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Six water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location 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: 0.001 mg/l Atrazine, and 0.004 mg/l Simazine (CCR, Title 22).
Guideline Reference: Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A
 
Spatial Representation: Samples were collected near the California Nevada Border.
Temporal Representation: Six water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October. No sample was collected in October 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
102942
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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.

Seven lines of evidence are available in the administrative record to assess this pollutant.

None of the samples exceeded 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 water samples exceeded the objectives. Sample sizes were less that 16 for each matrix/fraction/beneficial use/objective combination.

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 102942, Azinphos-methyl (Guthion)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128482
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 1 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: 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: 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 to 2010-10-04
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 102942, Azinphos-methyl (Guthion)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35287
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 102942, Azinphos-methyl (Guthion)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 29444
 
Pollutant: Azinphos, Ethyl (Ethyl Guthion) | Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances:
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Five water samples were collected from 5/2002 through 5/2004 at 1 location in the river (SWAMP, 2006).
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 2004.
 
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: Samples were collected near the California Nevada Border.
Temporal Representation: Five water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2004 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 102942, Azinphos-methyl (Guthion)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128922
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 1 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: 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: 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 to 2010-10-04
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 102942, Azinphos-methyl (Guthion)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35307
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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
77976
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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 the samples exceed the water quality objective for each beneficial use assessed. Eight water samples were collected, but six 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. 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 77976, Bifenthrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 46341
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 77976, Bifenthrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127848
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Bifenthrin.
Data 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 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 77976, Bifenthrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 46340
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 77976, Bifenthrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128674
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Bifenthrin.
Data 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 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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
77978
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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 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. Zero of seven water samples exceeded the California State Notification Level criterion.

Zero of one water sample exceeded the Water Quality for Agriculture, (published by the Food and Agriculture Organization of the United Nations in 1985) 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 77978, Boron
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127272
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Boron.
Data 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) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 77978, Boron
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127273
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Boron.
Data 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) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 77978, Boron
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 33625
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 713CRNVBD (Colorado River at Nevada State Line).
Temporal Representation: Samples were collected on 10/24/2005, 5/2/2006, 5/7/2007, 10/22/2007, 4/21/2008 and 10/28/2008.
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
70632
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 section 3.1 and 3.5 of the Listing Policy. Under section 3.1 and 3.5 a single line of evidence is necessary to assess listing status.

Nine 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 the samples exceed the water quality objective. The sample sizes for each the matrix, fraction, beneficial uses, and objective are less than 16.

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 70632, Cadmium
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35228
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Cadmium.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Maximum Contaminant Levels for organic and inorganic chemicals. CCR
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 70632, Cadmium
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128811
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Cadmium.
Data 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 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 70632, Cadmium
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7629
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Five water samples were collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (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: California Toxics Rule (CTR) Hardness Dependant Criterion Maximum Concentration (CMC) for the protection of freshwater aquatic life uses (USEPA, 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: Samples were collected near the California Nevada Border.
Temporal Representation: Five water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 70632, Cadmium
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128810
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Cadmium.
Data 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 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 70632, Cadmium
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128812
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Cadmium.
Data 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 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 70632, Cadmium
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7691
 
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: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the Basin Plan Objective (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: 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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 70632, Cadmium
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 32833
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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 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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples collected at station 713CRNVBD (Colorado River at Nevada State Line).
Temporal Representation: Samples collected between 10/24/2005 and 10/28/2008.
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 70632, Cadmium
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 45926
 
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: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium. One composite (6 fish per composite) were generated from one species: largemouth bass.
Data Reference: RWB7 Fish Tissue Study 2004
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 12/9/2004.
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 70632, Cadmium
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7673
 
Pollutant: 1, 1-dichloroethane | 1,1,1-Trichloroethane | 1,1,2-Trichloroethane | 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride | 1,2,4-Trichlorobenzene | 1,2-Dichloroethylene,-trans | 1,2-Dichloropropane | Aluminum | Arsenic | Benzo(a)pyrene (3,4-Benzopyrene -7-d) | Cadmium | Chlordane | Chlorobenzene (mono) | Chromium (total) | Endrin | Ethylbenzene | Heptachlor | Heptachlor epoxide | Hexachlorobenzene/ HCB | Lindane/gamma Hexachlorocyclohexane (gamma-HCH) | Mercury | Methoxychlor | Methyl Tertiary-Butyl Ether (MTBE) | Molinate | Nickel | Nitrate | Nitrogen, Nitrite | PCBs (Polychlorinated biphenyls) | Selenium | Tetrachloroethylene/PCE | Thiobencarb/Bolero | Toluene | Trichloroethylene/TCE | Xylenes (total) (mixed) | cis-1,2-Dichloroethylene | o-Dichlorobenzene | p-Dichlorobenzene (DCB)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location 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 near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management 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
102967
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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 the water samples exceeded the objectives.
Zero of one total fraction water sample(s) exceeded the Drinking water notification levels for Carbophenothion (Trithion) of 0.007 mg/L.

Zero of five dissolved fraction water samples 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

Sample sizes were less that 16 for each matrix/fraction/beneficial use/objective combination.

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 102967, Carbophenothion
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128883
 
Pollutant: Carbophenothion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Carbophenothion.
Data 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 Carbophenothion (Trithion) is 0.007 mg/L.
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) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 102967, Carbophenothion
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 29448
 
Pollutant: Carbophenothion | Dichlofenthion | Dioxathion | Ethion | Fenitrothion | Fensulfothion | Fenthion | Malathion | Methidathion | Methyl Parathion | Parathion | Tokuthion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances:
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Five water samples were collected from 5/2002 through 5/2004 at 1 location in the river (SWAMP, 2006).
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 2004.
 
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: Samples were collected near the California Nevada Border.
Temporal Representation: Five water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2004 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management 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
71099
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 section 3.1 and 3.5 of the Listing Policy. Under section 3.1 and 3.5 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 the samples exceeded the objectives. Sample sizes were less that 16 for each matrix/fraction/beneficial use/objective combination.

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 71099, Chlordane
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 32993
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples collected at station 713CRNVBD Colorado River at Nevada State Line
Temporal Representation: Samples collected between 10/24/2005 and 10/28/2008.
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 71099, Chlordane
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127337
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Chlordane.
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 71099, Chlordane
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 45927
 
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: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Fish Tissue Study 2004
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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.
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 for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 12/9/2004.
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 71099, Chlordane
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 45929
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Fish Tissue Study 2004
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 12/9/2004.
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 71099, Chlordane
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 33174
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples collected at station 713CRNVBD Colorado River at Nevada State Line
Temporal Representation: Samples collected between 10/24/2005 and 10/28/2008.
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 71099, Chlordane
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7673
 
Pollutant: 1, 1-dichloroethane | 1,1,1-Trichloroethane | 1,1,2-Trichloroethane | 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride | 1,2,4-Trichlorobenzene | 1,2-Dichloroethylene,-trans | 1,2-Dichloropropane | Aluminum | Arsenic | Benzo(a)pyrene (3,4-Benzopyrene -7-d) | Cadmium | Chlordane | Chlorobenzene (mono) | Chromium (total) | Endrin | Ethylbenzene | Heptachlor | Heptachlor epoxide | Hexachlorobenzene/ HCB | Lindane/gamma Hexachlorocyclohexane (gamma-HCH) | Mercury | Methoxychlor | Methyl Tertiary-Butyl Ether (MTBE) | Molinate | Nickel | Nitrate | Nitrogen, Nitrite | PCBs (Polychlorinated biphenyls) | Selenium | Tetrachloroethylene/PCE | Thiobencarb/Bolero | Toluene | Trichloroethylene/TCE | Xylenes (total) (mixed) | cis-1,2-Dichloroethylene | o-Dichlorobenzene | p-Dichlorobenzene (DCB)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location 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 near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71099, Chlordane
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7632
 
Pollutant: Aldrin | Arsenic | Chlordane | Chromium (total) | Dieldrin | Endrin | Heptachlor | Heptachlor epoxide | alpha-Endosulfan (Endosulfan 1) | beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (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: 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: 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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71099, Chlordane
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 45928
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Fish Tissue Study 2004
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 12/9/2004.
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
102968
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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(s) of evidence is available in the administrative record to assess this pollutant.

Zero of zero samples exceed the criteria for the protection of human health from the consumption of water and organisms of 0.00057 ug/L (California Toxics Rule, 2000). Although a total of 1 samples were collected, the sample was 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. None of the water samples exceeded the objectives.
Zero of zero samples exceed the criteria for the protection of human health from the consumption of water and organisms of 0.00057 ug/L (California Toxics Rule, 2000). Although a total of 1 samples were collected, the sample was 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 102968, Chlordane, cis
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128902
 
Pollutant: Chlordane, cis
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 1 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: 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: 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 to 2010-10-04
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
102969
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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(s) of evidence is available in the administrative record to assess this pollutant.

Zero of zero samples exceed the criteria for the protection of human health from the consumption of water and organisms of 0.00057 ug/L (California Toxics Rule, 2000). Although a total of 1 samples were collected, the sample was 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. None of the water samples exceeded the objectives.
Zero of zero samples exceed the criteria for the protection of human health from the consumption of water and organisms of 0.00057 ug/L (California Toxics Rule, 2000). Although a total of 1 samples were collected, the sample was 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 102969, Chlordane, trans
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127922
 
Pollutant: Chlordane, trans
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 1 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: 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: 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 to 2010-10-04
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
71100
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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.

Five lines of evidence are available in the administrative record to assess this pollutant.

Zero 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 ten dissolved fraction water samples exceed the guideline for the "Municipal & Domestic Supply" beneficial use assessed.

Zero of the three dissolved fraction water samples exceed the guideline for "Cold Freshwater Habitat" beneficial use assessed.

Zero of the three dissolved fraction water samples exceed the guideline for the "Warm Freshwater Habitat" beneficial use assessed.

Zero of the six total fraction water samples exceed the guideline for the "Warm Freshwater Habitat" beneficial use assessed.

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 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 71100, Chloride
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128101
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Chloride.
Data 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 71100, Chloride
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7677
 
Pollutant: Aluminum | Chloride | Copper | Manganese | Methyl Tertiary-Butyl Ether (MTBE) | Silver | Sulfates | Thiobencarb/Bolero | Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the CDPH SMCL (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 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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71100, Chloride
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128102
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Chloride.
Data 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 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 71100, Chloride
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128104
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Chloride.
Data 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 71100, Chloride
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 33104
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at station713CRNVBD (Colorado River at Nevada State Line).
Temporal Representation: Samples were collected on 10/24/2005, 5/2/2006, 5/7/2007, 10/22/2007, 4/21/2008, and 10/28/2008.
Environmental Conditions:
QAPP Information: SWAMP QAPP (2008).
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
78378
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 and 3.5 of the Listing Policy. Under section 3.1 and 3.5 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 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 one fish tissue sample exceeded the OEHHA fish contaminant goal, for the Commercial or recreational collection of fish, shellfish, or organisms"
beneficial use assessed.

Zero of zero water samples exceeded the freshwater criterion continuous concentration to protect aquatic organisms (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005), for the "Cold Freshwater Habitat" and "Warm Freshwater Habitat"
beneficial use assessed. Seven water samples were collected, 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.

Zero of one water samples exceeded the USEPA drinking water health advisory for lifetime exposure, for the "Municipal & Domestic Supply" beneficial use assessed.

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 78378, Chlorpyrifos
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128225
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Chlorpyrifos.
Data 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 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 78378, Chlorpyrifos
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35189
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 78378, Chlorpyrifos
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128957
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 1 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: 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 to 2010-10-04
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 78378, Chlorpyrifos
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127371
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 1 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: 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 to 2010-10-04
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 78378, Chlorpyrifos
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 45930
 
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: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlorpyrifos. One composite (6 fish per composite) were generated from one species: largemouth bass.
Data Reference: RWB7 Fish Tissue Study 2004
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 12/9/2004.
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 78378, Chlorpyrifos
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35186
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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
102970
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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.

Three lines of evidence are available in the administrative record to assess this pollutant.

Zero of one sample(s) exceed the USEPA Aquatic Life Benchmark of 0.085 ug/L for an invertebrate (acute), for the "Cold Freshwater Habitat" beneficial use assessed.

Zero of one sample(s) exceed the USEPA Aquatic Life Benchmark of 0.085 ug/L for an invertebrate (acute), for the "Warm Freshwater Habitat"
beneficial use assessed.

Zero of five sample(s) exceed the objective when there was 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, for the "Warm 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 one sample(s) exceed the USEPA Aquatic Life Benchmark of 0.085 ug/L for an invertebrate (acute), for the "Cold Freshwater Habitat" beneficial use assessed.

Zero of one sample(s) exceed the USEPA Aquatic Life Benchmark of 0.085 ug/L for an invertebrate (acute), for the "Warm Freshwater Habitat"
beneficial use assessed.

Zero of five sample(s) exceed the objective when there was 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, for the "Warm Freshwater Habitat" beneficial use assessed.

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 102970, Chlorpyrifos, methyl
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127866
 
Pollutant: Chlorpyrifos, methyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Chlorpyrifos Methyl.
Data 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: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 102970, Chlorpyrifos, methyl
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127867
 
Pollutant: Chlorpyrifos, methyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Chlorpyrifos Methyl.
Data 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: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 102970, Chlorpyrifos, methyl
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 29449
 
Pollutant: Chlorfenvinphos | Chlorpyrifos, methyl | Cuomaphos | Dicrotophos | Dyfonate (Fonofos or Fonophos) | Fenchlorphos | Leptophos | Merphos | Mevinphos | Tetrachlorvinphos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances:
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Five water samples were collected from 5/2002 through 5/2004 at 1 location in the river (SWAMP, 2006).
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 2004.
 
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: Samples were collected near the California Nevada Border.
Temporal Representation: Five water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2004 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management 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
71637
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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 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 samples exceed the water quality objective.

Sample sizes for each matrix, fraction, beneficial use and objective were less than 16.

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 71637, Chromium (total)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128706
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Chromium.
Data 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 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 71637, Chromium (total)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7632
 
Pollutant: Aldrin | Arsenic | Chlordane | Chromium (total) | Dieldrin | Endrin | Heptachlor | Heptachlor epoxide | alpha-Endosulfan (Endosulfan 1) | beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (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: 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: 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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71637, Chromium (total)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7673
 
Pollutant: 1, 1-dichloroethane | 1,1,1-Trichloroethane | 1,1,2-Trichloroethane | 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride | 1,2,4-Trichlorobenzene | 1,2-Dichloroethylene,-trans | 1,2-Dichloropropane | Aluminum | Arsenic | Benzo(a)pyrene (3,4-Benzopyrene -7-d) | Cadmium | Chlordane | Chlorobenzene (mono) | Chromium (total) | Endrin | Ethylbenzene | Heptachlor | Heptachlor epoxide | Hexachlorobenzene/ HCB | Lindane/gamma Hexachlorocyclohexane (gamma-HCH) | Mercury | Methoxychlor | Methyl Tertiary-Butyl Ether (MTBE) | Molinate | Nickel | Nitrate | Nitrogen, Nitrite | PCBs (Polychlorinated biphenyls) | Selenium | Tetrachloroethylene/PCE | Thiobencarb/Bolero | Toluene | Trichloroethylene/TCE | Xylenes (total) (mixed) | cis-1,2-Dichloroethylene | o-Dichlorobenzene | p-Dichlorobenzene (DCB)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location 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 near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71637, Chromium (total)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128707
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Chromium.
Data 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 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 71637, Chromium (total)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 33923
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples collected at stations 713CRNVBD (Colorado River at Nevada State Line).
Temporal Representation: Samples collected between 10/24/05 and 10/28/08.
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 71637, Chromium (total)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 34302
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Maximum Contaminant Levels for organic and inorganic chemicals. CCR
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples collected at stations 713CRNVBD (Colorado River at Nevada State Line).
Temporal Representation: Samples collected between 10/24/05 and 10/28/08.
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 71637, Chromium (total)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128708
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Chromium.
Data 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 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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
102978
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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.

Four lines of evidence are available in the administrative record to assess this pollutant.

Zero of two samples exceed the USEPA Aquatic Life Benchmark an invertebrate (chronic) for each type of Cinerin assessed: Cinerin-1 and Cinerin-2, for each beneficial use assessed: "Warm Freshwater Habitat" and "Cold Freshwater Habitat."

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 two samples exceed the USEPA Aquatic Life Benchmark an invertebrate (chronic) for each pollutant: Cinerin-1 and Cinerin-2, for each beneficial use assessed: "Warm Freshwater Habitat" and "Cold Freshwater Habitat."

This 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 3.2.
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 102978, Cinerin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127363
 
Pollutant: Cinerin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Cinerin-2.
Data 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: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2013-04-15 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 102978, Cinerin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128038
 
Pollutant: Cinerin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Cinerin-1.
Data 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: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2013-04-15 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 102978, Cinerin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127364
 
Pollutant: Cinerin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Cinerin-2.
Data 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: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2013-04-15 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 102978, Cinerin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128037
 
Pollutant: Cinerin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Cinerin-1.
Data 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: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2013-04-15 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
71157
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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 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 the samples exceed the water quality objective.

Sample sizes for each matrix, fraction, beneficial use and objective were less than 16.

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 71157, Copper
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7683
 
Pollutant: Arsenic | Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the USFWS Biological Effect Criteria (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. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).
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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71157, Copper
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7677
 
Pollutant: Aluminum | Chloride | Copper | Manganese | Methyl Tertiary-Butyl Ether (MTBE) | Silver | Sulfates | Thiobencarb/Bolero | Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were generally collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the CDPH SMCL (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 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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71157, Copper
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128266
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Copper.
Data 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 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 71157, Copper
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35275
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Copper.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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 Colorado River Basin, with amendments adopted through June 2006
 
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 (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 71157, Copper
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128268
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Copper.
Data 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 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 71157, Copper
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7616
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the CTR Criteria (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: California Toxics Rule Hardness Dependent Criterion Maximum Concentration (CMC) for the protection of freshwater aquatic life uses (USEPA, 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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71157, Copper
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128267
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Copper.
Data 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 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 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 71157, Copper
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 32855
 
Pollutant: Copper, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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 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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples collected at station 713CRNVBD (Colorado River at Nevada State Line).
Temporal Representation: Samples collected between 10/24/2005 and 10/28/2008.
Environmental Conditions:
QAPP Information: SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
102982
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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 is necessary to assess listing status.

Two lines of evidence is available in the administrative record to assess this pollutant.

Zero of zero samples exceed the USEPA Aquatic Life Benchmark for an invertebrate (chronic) for the beneficial uses assessed.

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

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 zero samples exceed the USEPA Aquatic Life Benchmark for an invertebrate (chronic) for the beneficial uses assessed.

Although one sample were collected, it was 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 102982, Coumaphos
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128970
 
Pollutant: Coumaphos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 1 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: 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: OPP Aquatic Life Benchmarks
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 to 2010-10-04
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 102982, Coumaphos
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127015
 
Pollutant: Coumaphos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 1 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: 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: OPP Aquatic Life Benchmarks
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 to 2010-10-04
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
78176
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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.

Zero of two sample(s) exceed the water quality objectives for each of the two beneficial uses assessed: "Cold Freshwater Habitat" and "Warm Freshwater Habitat"

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 two sample(s) exceed the water quality objectives for each of the two beneficial uses assessed: "Cold Freshwater Habitat" and "Warm Freshwater Habitat"

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 78176, Cyanazine
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127905
 
Pollutant: Cyanazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Cyanazine.
Data 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 indigenous aquatic life. (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: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Cyanazine is 4.8 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 78176, Cyanazine
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127904
 
Pollutant: Cyanazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Cyanazine.
Data 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 indigenous aquatic life. (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: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Cyanazine is 4.8 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 78176, Cyanazine
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35319
 
Pollutant: Cyanazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyanazine.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 10/28/2008.
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 78176, Cyanazine
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35320
 
Pollutant: Cyanazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyanazine.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 10/28/2008.
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
76552
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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. Eight 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.

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 76552, Cyfluthrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 46363
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 76552, Cyfluthrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128895
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 2 samples were collected, 2 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 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 76552, Cyfluthrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 46372
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 76552, Cyfluthrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 129012
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 2 samples were collected, 2 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 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
79414
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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. Eight 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.

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 79414, Cyhalothrin, Lambda
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127969
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 2 samples were collected, 2 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 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 79414, Cyhalothrin, Lambda
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128951
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 2 samples were collected, 2 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 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 79414, Cyhalothrin, Lambda
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 46332
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 79414, Cyhalothrin, Lambda
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 46333
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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
79415
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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

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. Zero of one sediment samples exceeded the median lethal concentration (LC50).

Eight 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 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 79415, Cypermethrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128716
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 2 samples were collected, 2 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: 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. (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: 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 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 79415, Cypermethrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127043
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 2 samples were collected, 2 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: 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: 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 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 79415, Cypermethrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127984
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 2 samples were collected, 2 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: 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: 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 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 79415, Cypermethrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 46355
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 79415, Cypermethrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128023
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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 2 samples were collected, 2 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: 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. (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: 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 1 station(s) (Station Code(s) 713CRNVBD).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-04 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 79415, Cypermethrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 125629
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data 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 1 (Station Codes: 713CRNVBD).
Temporal Representation: Data for this waterbody were collected over the date range 2013-04-15 to 2013-04-15
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 79415, Cypermethrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 125795
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data 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 1 (Station Codes: 713CRNVBD).
Temporal Representation: Data for this waterbody were collected over the date range 2013-04-15 to 2013-04-15
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 79415, Cypermethrin
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 46356
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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
102999
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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 the samples exceed the water quality objectives.

The method detection limit for 6 of the non-detect samples was greater than the criteria, thus the data was not used in this assessment.

Sample sizes for each matrix/fraction/beneficial use/objective combination were less than 16.

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 102999, DDD (Dichlorodiphenyldichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128648
 
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: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for DDD (Dichlorodiphenyldichloroethane).
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 102999, DDD (Dichlorodiphenyldichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128649
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for DDD (Dichlorodiphenyldichloroethane).
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 102999, DDD (Dichlorodiphenyldichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 34527
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples collected at stations 713CRNVBD (Colorado River at Nevada State Line).
Temporal Representation: Samples collected between 10/24/2005 and 10/28/2008.
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 102999, DDD (Dichlorodiphenyldichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 29446
 
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: 5
Number of Exceedances:
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Five water samples were collected from 5/2002 through 5/2004 at 1 location in the river (SWAMP, 2006).
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 2004.
 
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 marine 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 near the California Nevada Border.
Temporal Representation: Five water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2004 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management 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
103000
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
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 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 the samples exceed the water quality objective.

The method detection limit for 6 of the non-detect samples was greater than the criteria, thus the data was not used in this assessment.

Sample sizes for each matrix, fraction, beneficial use and objective were less than 16.

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 103000, DDE (Dichlorodiphenyldichloroethylene)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127795
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for DDE (Dichlorodiphenyldichloroethylene).
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 103000, DDE (Dichlorodiphenyldichloroethylene)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 34528
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples collected at stations 713CRNVBD (Colorado River at Nevada State Line).
Temporal Representation: Samples collected between 10/24/2005 and 10/28/2008.
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 103000, DDE (Dichlorodiphenyldichloroethylene)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 29446
 
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: 5
Number of Exceedances:
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Five water samples were collected from 5/2002 through 5/2004 at 1 location in the river (SWAMP, 2006).
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 2004.
 
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 marine 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 near the California Nevada Border.
Temporal Representation: Five water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2004 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 103000, DDE (Dichlorodiphenyldichloroethylene)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 127796
 
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: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for DDE (Dichlorodiphenyldichloroethylene).
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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
71533
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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.

Ten 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 samples exceed the water quality objective.

The method detection limit for 6 of the non-detect samples was greater than the criteria, thus the data was not used in this assessment.

Sample sizes for each matrix, fraction, beneficial use and objective were less than 16.

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 71533, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 45933
 
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: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Fish Tissue Study 2004
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 12/9/2004.
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 71533, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 45931
 
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: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Fish Tissue Study 2004
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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.
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 for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 12/9/2004.
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 71533, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 45932
 
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: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) 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: RWB7 Fish Tissue Study 2004
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
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 for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected on a single day 12/9/2004.
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 71533, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128417
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for DDT (Dichlorodiphenyltrichloroethane).
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 71533, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 34526
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples collected at stations 713CRNVBD (Colorado River at Nevada State Line).
Temporal Representation: Samples collected between 10/24/2005 and 10/28/2008.
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 71533, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128414
 
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: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for DDT (Dichlorodiphenyltrichloroethane).
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 71533, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 34525
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: 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
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples collected at stations 713CRNVBD (Colorado River at Nevada State Line).
Temporal Representation: Samples collected between 10/24/2005 and 10/28/2008.
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 71533, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128415
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for DDT (Dichlorodiphenyltrichloroethane).
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 71533, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 7641
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Seven water samples were collected biannually from 5/2002 through 5/2005 at 1 location along this segment of the Colorado River. Of these total samples, none exceeded the CTR criteria (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: 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: 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: Samples were collected near the California Nevada Border.
Temporal Representation: Seven water samples were collected. Water samples were generally collected and analyzed biannually from 5/2002 through 5/2005 from the Nevada Border. Samples were usually collected in May and October.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71533, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128418
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for DDT (Dichlorodiphenyltrichloroethane).
Data 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: 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: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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
80108
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
Pollutant: Dacthal
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 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 samples exceed the water quality objective.
The sample sizes are less than 16.
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 80108, Dacthal
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35004
 
Pollutant: Dacthal
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Dacthal.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50 for Dacthal 6600 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line - 713CRNVBD]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 80108, Dacthal
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 35342
 
Pollutant: Dacthal
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Dacthal.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
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 Colorado River Basin, with amendments adopted through June 2006
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu) was collected at 1 monitoring site [ Colorado River at Nevada State Line]
Temporal Representation: Data was collected over the time period 10/24/2005-10/28/2008.
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 80108, Dacthal
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128610
 
Pollutant: Dacthal
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Dacthal.
Data 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 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 80108, Dacthal
Region 7     
Colorado River and Associated Lakes and Reservoirs (California-Nevada border to Lake Havasu)
 
LOE ID: 128661
 
Pollutant: Dacthal
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 (California-Nevada border to Lake Havasu) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Dacthal.
Data 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: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (713CRNVBD)
Temporal Representation: The samples were collected between the dates of 2010-10-04 and 2010-10-04
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 80108, Dacthal
Region 7