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

Supporting Information

Regional Board 7 - Colorado River Basin Region

Water Body Name: Alamo River
Water Body ID: CAR7231000019990205093023
Water Body Type: River & Stream
 
DECISION ID
79439
Region 7     
Alamo River
 
Pollutant: Endosulfan
Final Listing Decision: Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (TMDL required list)(2016)
Revision Status Revised
Reason for Delisting: Applicable WQS attained; reason for recovery unspecified
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the section 303(d) list under section 4.11 of the Listing Policy. Under this section when all other delisting factors do not result in the delisting of a water segment but information indicates attainment of standards, a water segment shall be evalauted to determine whether the weight of evidence demonstrates that water quality standard is attained. If the weight of evidence indicates attainment, the water segment shall be removed from the section 303(d) list.

Twelve lines of evidence are available in the administrative record to assess pollutant. LOE No. 5470 is replaced by the 46599, which is re-assessed based on the current evaluation guideline, and is not use the final use rating.

Four of 35 total fraction fish tissue samples colledted from 1985 to 1988 exceeded the National Academy of Science guidelines.

Organochlorine (OC) pesticides are man-made chemicals. There are no natural sources of these OC compounds. Endosulfan is one of the OC compounds, which was used for mainly agricultural uses during 1980s and 1990s. However, USEPA has initiated action to end the use of Endosulfan based on the Endosulfan Memorandum of Agreement in 2010. The use of Endosulfan is phasing out, and the registrants of Endosulfan are voluntarily cancelling all existing Endosulfan uses.

Since OC compounds are attached to sediments, sediment management practices (MPs) plays important roles in reducing the compounds. Two USEPA approved TMDLs, Alamo River Sediment Total Maximum Daily Load (TMDL) and Imperial Valley Drains (IVDs) Sediment TMDL and Prohibition, are already in place in Imperial County, which requires farmers/growers to implement improved sediment MPs.

According to the CA Department of Pesticide Regulations (DPR) pesticide use reporting (PUR), the annual use of Endosulfan in Imperial County, where this waterbody is located, is significantly reduced past 20 years. The reported annual Endosulfan uses were 247, 400 pounds in 1990, and the amount reduced to 22 pounds in 2010. Although Endosulfan was used for Alfalfa seed, a major crop produced in the Imperial County, farmers in Imperial County stopped its use since 2011. No uses of Endosulfan were reported in PUR, in 2011, in the Imperial County.

None of 22 fish fillet fraction fish tissue samples collected from 2004 - 2014 exceeded National Academy of Science guideline for the protection of aquatic life uses of 100 ug/kg.

None of 12 water samples collected from 2005 - 2008 exceeded the USEPA National Recommended Water Quality Criteria criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater of 0.056 ug/L.

None of 23 water samples collected from 2010 - 2013 exceeded the California Toxics Rule criteria for the protection of human health from consumption of organisms of 240 ug/L.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the section 303(d) list.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.

2. Four of 35 total fraction fish tissue samples colleted from 1985 to 1988 exceeded the National Academy of Science guidelines and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. However, the uses of Endosulfan is phasing out; the farmers have stopped using the Endosulfan for Alfalfa seed since 2011. The last exceedance occurred on 11/20/1988. Data collected from 2004 -2014, indicates that the water quality standard is attained:

None of 22 fish fillet fraction fish tissue samples collected from 2004 - 2014 exceeded National Academy of Science guideline for the protection of aquatic life uses of 100 ug/kg.

None of 12 water samples collected from 2005 - 2008 exceeded the USEPA National Recommended Water Quality Criteria criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater of 0.056 ug/L.

None of 23 water samples collected from 2010 - 2013 exceeded the California Toxics Rule criteria for the protection of human health from consumption of organisms of 240 ug/L.

3. This process is scientifically defensible and reproducible.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 33087
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 12 samples exceeded the criteria.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The endosulfan criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L. This value corresponds to the sum of alpha-endosulfan and beta-endosulfan (USEPA National Recommended Water Quality Criteria, 2006).
Objective/Criterion Reference: 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 were collected at stations 723ARGRB1 (Alamo River Outlet) and 723ARINTL (Alamo River at International Boundary).
Temporal Representation: Samples were collected on 10/26/2005, 5/1/2006, 5/7/2007, 10/23/2007, 4/21/2008, and 10/23/2008.
Environmental Conditions:
QAPP Information: SWAMP QAPP (2008).
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 128324
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 RWB7 TMDL data for Alamo River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Endosulfan.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Endosulfan criterion (for the total concentrations of alpha-endosulfan [Endosulfan I] and beta-endosulfan [Endosulfan II]) for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: 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 2 monitoring site(s) (723ARGRB1, 723ARDP10)
Temporal Representation: The samples were collected between the dates of 2011-02-11 and 2011-04-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 127799
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 20
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 Alamo River to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality standard for Endosulfan.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Endosulfan criterion (for the total concentrations of alpha-endosulfan [Endosulfan I] and beta-endosulfan [Endosulfan II]) for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: 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 7 monitoring site(s) (723ARGRB1, 723ARINTL, 723ARDP06, 723ARDP10, 723ARDP3A, 723ARDP6A, 723NRRCD3)
Temporal Representation: The samples were collected between the dates of 2010-10-05 and 2013-10-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 5595
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 35
Number of Exceedances: 4
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. The fish tissue samples were generally collected from 6/1978 through 11/2000. Of these total samples, 4 fish fillet samples from two locations exceeded the NAS tissue guideline. At the Calipatria location the exceedances were found in; 1 channel catfish fillet composite sample collected on 9/30/1987, and; 1 carp fillet composite sample collected on 11/18/1988. At the International Boundary location, exceedances were found in; 1 carp fillet composite sample collected on 11/20/1998, and; 1 largemouth bass fillet composite sample collected on 11/15/1985 (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples of channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000. The exceedances were found in samples collected from 11/15/1985 through 11/20/1998.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 46599
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 35
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish samples were generally collected from 6/1978 through 11/2000.
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: The modified OEHHA Fish Contaminant Goal for endosulfan (l and ll) in fish tissue is 13,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets.
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: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Calipatria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples of channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 46022
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Endosulfan, Total. Nine composites were generated from three species: channel catfish, flathead catfish and Tilapia spp. Composites comprised of 2-3 fish for channel catfish and 1 fish for flathead catfish and Tilapia spp. Total endosulfan was calculated as the sum of endosulfan l and endosulfan ll. Composites collected at the same time on the same day for the same species were averaged in accordance with the listing policy.
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 endosulfan (l and ll) in fish tissue is 13,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets.
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 Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 46023
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Endosulfan, Total. Nine composites were generated from three species: channel catfish, flathead catfish and Tilapia spp. Composites comprised of 2-3 fish for channel catfish and 1 fish for flathead catfish and Tilapia spp. Total endosulfan was calculated as the sum of endosulfan l and endosulfan ll. Composites collected at the same time on the same day for the same species were averaged in accordance with the listing policy.
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 Endosulfan concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 126478
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
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 Alamo River to determine beneficial use support and the results are as follows 0 of the 11 samples exceeded the water quality standard for Endosulfan. Data were collected for 6 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Common Carp each composed of 3 fish per composite, 3 composite(s) of Common Carp each composed of 5 fish per composite, 2 composite(s) of Tilapia spp. each composed of 5 fish per composite, 1 composite(s) of Common Carp each composed of 8 fish per composite).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Endosulfan, Total concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data was collected from 4 station(s) with the station code(s): 723ARINTL, 723ARDP3A, 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2012-03-28 and 2014-12-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 126467
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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 RWB7 TMDL data for Alamo River to determine beneficial use support and the results are as follows 0 of the 6 samples exceeded the water quality standard for Endosulfan. Data were collected for 5 fish species (1 composite(s) of Channel Catfish each composed of 2 fish per composite, 2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 4 fish per composite).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Endosulfan, Total concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2011-02-08 and 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 126224
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB7 TMDL data for Alamo River to determine beneficial use support and the results are as follows 0 of the 6 samples exceeded the water quality standard for Endosulfan. Data were collected for 5 fish species (1 composite(s) of Channel Catfish each composed of 2 fish per composite, 2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 4 fish per composite).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for endosulfan (l and ll) in fish tissue is 13,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
  Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2011-02-08 and 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 126643
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 11
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 Alamo River to determine beneficial use support and the results are as follows 0 of the 11 samples exceeded the water quality standard for Endosulfan. Data were collected for 6 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Common Carp each composed of 3 fish per composite, 3 composite(s) of Common Carp each composed of 5 fish per composite, 2 composite(s) of Tilapia spp. each composed of 5 fish per composite, 1 composite(s) of Common Carp each composed of 8 fish per composite).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for endosulfan (l and ll) in fish tissue is 13,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
  Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: Data was collected from 4 station(s) with the station code(s): 723ARINTL, 723ARDP3A, 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2012-03-28 and 2014-12-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 79439, Endosulfan
Region 7     
Alamo River
 
LOE ID: 5470
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 35
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish samples were generally collected from 6/1978 through 11/2000. Of these total samples, none exceeded the OEHHA Screening Value (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: Office of Environmental Health Hazard Assessment (OEHHA) Screening Value of 20,000 ug/kg to protect human health when consuming fish (OEHHA, 1999).
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Calipatria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples of channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
 
DECISION ID
71071
Region 7     
Alamo River
 
Pollutant: Chlordane
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the section 303(d) list under sections 2.2 and 4.5 of the Listing Policy.

Under these sections of the Policy, a minimum of one line of evidence is needed to assess listing status.

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

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Twenty-four of 35 total fraction fish tissue samples exceed the Office of Environmental Health Hazard Assessment (OEHHA) Fish Contaminant Goal.

Eight of 21 fish fillet fraction fish tissue samples exceed the modified Office of Environmental Health Hazard Assessment (OEHHA) Fish Contaminant Goal.

These exceed the allowable frequency listed in Table 4.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be 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 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 5377
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 35
Number of Exceedances: 24
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. The fish tissue samples were generally collected from 6/1978 through 11/2000. Of these total samples, 23 fish fillet samples and 1 whole fish samples collected at two locations exceeded the OEHHA Fish Contaminant Goal. At the Calipatria location the exceedances were found in; 11 Channel Catfish fillet composite samples collected on 3/12/1979, 5/08/1980, 5/23/1981, 4/22/1982, 6/13/1983, 5/23/1984, 9/17/1985, 9/30/1987, 11/01/1996, 11/20/1997, and 11/11/1998; 1 channel catfish single fish fillet on 10/27/1994; 8 Carp fillet composite samples collected on 5/23/1981, 4/22/1982, 6/13/1983, 5/23/1984, 9/17/1985, 11/18/1988, 8/03/1990, and 9/29/1993, and; 2 Carp single fish fillet samples on 10/27/1994, and 11/07/2000. At the International Boundary location the exceedances were found in; 1 carp fillet composite sample collected on 11/20/1998, and; 1 Mosquitofish whole fish composite sample collected on 9/02/1987. (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: Office of Environmental Health Hazard Assessment (OEHHA) Fish Contaminant Goal of 5.6 ug/kg to protect human health when consuming fish (OEHHA, 2008).
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000. The exceedances were found in samples collected from 3/12/1979 through 11/07/2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 5576
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 35
Number of Exceedances: 1
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish tissue samples were generally collected from 6/1978 through 11/2000. Of these total samples, 1 whole fish sample collected at 1 location exceeded the NAS tissue guideline. At the International Boundary location an exceedance was found in 1 mosquitofish whole fish composite sample collected on 9/02/1987. (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Samples were collected from the following Alamo River locations:at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples of channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the years 1987. One tilapia whole fish composite sample was collected in the year 2000. An exceedence was found in a sample collected 9/02/1987.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 125659
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
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 Alamo River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline 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: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 6 (Station Codes: 723ARGRB1, 723ARDP6A, 723ARDP3A, 723ARDP06, 723ARINTL, 723ARDP10).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-05 to 2013-04-24
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 33650
 
Pollutant: Chlordane
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: The one sample collected was non-detect for chlordane concentration. (Sum of trans-Chlordane, cis-Chlordane, cis-Nonachlor, trans-Nonachlor, and Oxychlordane)
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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.
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: The Probable Effect Concentration for Chlordane in freshwater sediments is 17.6 ug/kg.
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station 723ARGRB1 (Alamo River Outlet).
Temporal Representation: One sample was collected on 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
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 33361
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 12 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 stations 723ARGRB1 (Alamo River Outlet) and 723ARINTL (Alamo River at International Boundary).
Temporal Representation: Samples collected between 10/25/2005 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 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 5006
 
Pollutant: Aldrin | Chlordane | 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: 14
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Fourteen water quality samples were collected and analyzed biannually from 5/2002 through 5/2005 at 2 locations along the Alamo 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, 0.22 ug/l beta-Endosulfan, 2.4 ug/l Chlordane, 0.24 ug/l Dieldrin, 0.086 ug/l Endrin, 0.52 ug/l Heptachlor, and 0.52 ug/l 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 from the following Alamo River locations: at the International Boundary, and near the outlet to the Salton Sea from Garst Road bridge.
Temporal Representation: Fourteen water samples were collected. Water samples were collected and analyzed biannually, in May and October, from 5/2002 through 5/2005.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 32847
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of 8 samples collected for Chlordane (Sum of trans-Chlordane, cis-Chlordane, cis-Nonachlor, trans-Nonachlor, and Oxychlordane)exceeded the evaluation guideline.
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. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (Colorado River Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: The Probable Effect Concentration for Chlordane in freshwater sediments is 17.6 ug/kg.
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station: Alamo River at International Boundary - 723ARINTL, Alamo River Outlet - 723ARGRB1.
Temporal Representation: The samples were collected on 10/25/2005 - 4/21/2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 125636
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Alamo River to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 (Station Codes: 723ARGRB1).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-06 to 2013-10-21
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 32373
 
Pollutant: Chlordane
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: The one sample collected was non-detect and did not exceeded the evaluation guideline.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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 (Colorado River Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: The Probable Effect Concentration for Chlordane (Sum of trans-Chlordane, cis-Chlordane, cis-Nonachlor, trans-Nonachlor, and Oxychlordane) in freshwater sediments is 17.6 ug/kg.
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station: Alamo River Outlet (723ARGRB1).
Temporal Representation: One sample was collected on 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
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 2882
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Data were collected by the RWQCB on 4/15/2003 at 7 different stations on the Alamo River. All samples were non-detects with a detection limit of 0.025 ppb, so there were no exceedances. Samples were also collected by the RWQCB on 6/21/2001 at 7 different stations on the Alamo River. All samples were non-detects, with a detection limit of 1 ppb, so there were no exceedances (CRBRWQCB, 2004C).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: USEPA: 2.4 ppb freshwater acute maximum and freshwater chronic maximum = 0.0043 ppb as a 4-day average.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at the following Alamo River sampling stations: AR-B (at the International Boundary), AR-D10 (Lower Alamo River drainshed, at Drop Structure #10), AR-D8 (Central Drain drainshed, at Drop Structure #8), AR-D6A (Holtville Main Drain drainshed, at Drop Structure #6A), AR-D6 (Rose Drain drainshed, at Drop Structure #6), AR-D3 (Central Alamo River drainshed, at Drop Structure #3), and at AR-GRB.
Temporal Representation: All samples were collected on 4/15/2003 and 6/21/2001.
Environmental Conditions:
QAPP Information: Used RWQCB QA/QC in sample collection. Lab analysis was done by E.S. Babcock & Sons laboratory and a Quality Assurance Manual was provided.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 126190
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
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 Alamo River to determine beneficial use support and the results are as follows 0 of the 11 samples exceeded the water quality standard for Total Chlordanes. Data were collected for 7 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Common Carp each composed of 3 fish per composite, 1 composite(s) of Common Carp each composed of 5 fish per composite, 3 composite(s) of Tilapia spp. each composed of 5 fish per composite, 1 composite(s) of Common Carp each composed of 8 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum total Chlordane concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data was collected from 4 station(s) with the station code(s): 723ARGRB1, 723ARDP3A, 723ARINTL, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2012-03-28 and 2014-12-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 46079
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Chlordane, Total. Nine composites were generated from three species: channel catfish, flathead catfish and Tilapia spp. Composites comprised of 2-3 fish for channel catfish and 1 fish for flathead catfish and Tilapia spp. Total chlordane was calculated as the sum of the following chlordane isomers: cis- and trans-chlordane, cis- and trans-nonachlor, and oxychlordane. Composites collected at the same time on the same day for the same species were averaged in accordance with the listing policy.
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 Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 126372
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB7 TMDL data for Alamo River to determine beneficial use support and the results are as follows 0 of the 5 samples exceeded the water quality standard for Total Chlordanes. Data were collected for 4 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 4 fish per composite).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum total Chlordane concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2011-04-21 and 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 126561
 
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: 5
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB7 TMDL data for Alamo River to determine beneficial use support and the results are as follows 2 of the 5 samples exceeded the water quality standard for Total Chlordanes. Data were collected for 4 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 4 fish per composite). Of these, 2 species (Channel Catfish, Flathead Catfish) exceeded the water quality standard.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total chlordane in fish tissue is 3.9 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2011-04-21 and 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 46078
 
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: 5
Number of Exceedances: 2
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 2 of 5 samples exceed the criterion for Chlordane, Total. Nine composites were generated from three species: channel catfish, flathead catfish and Tilapia spp. Composites comprised of 2-3 fish for channel catfish and 1 fish for flathead catfish and Tilapia spp. Total chlordane was calculated as the sum of the following chlordane isomers: cis- and trans-chlordane, cis- and trans-nonachlor, and oxychlordane. Composites collected at the same time on the same day for the same species were averaged in accordance with the listing policy.
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 Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 71071, Chlordane
Region 7     
Alamo River
 
LOE ID: 126191
 
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: 11
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and the results are as follows 4 of the 11 samples exceeded the water quality standard for Total Chlordanes. Data were collected for 7 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Common Carp each composed of 3 fish per composite, 1 composite(s) of Common Carp each composed of 5 fish per composite, 3 composite(s) of Tilapia spp. each composed of 5 fish per composite, 1 composite(s) of Common Carp each composed of 8 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite). Of these, 3 species (Common Carp, Flathead Catfish, Channel Catfish) exceeded the water quality standard.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total chlordane in fish tissue is 3.9 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 4 station(s) with the station code(s): 723ARGRB1, 723ARDP3A, 723ARINTL, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2012-03-28 and 2014-12-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
71978
Region 7     
Alamo River
 
Pollutant: Chloride
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 placement on the section 303(d) list under section 3.2 of the Listing Policy.

Under section 3.2 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. LOE 127340 was not used in the final use rating because sampling dates overlap with LOE 127339.

Ten of 12 "total" fraction and 25 of 25 "dissolved" fraction samples exceeded the USEPA National Recommended Water Quality Criteria, criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater.

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 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. Ten of 12 total fraction and 25 of 25 dissolved fraction samples exceeded the USEPA National Recommended Water Quality Criteria.

This exceeds the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should 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 71978, Chloride
Region 7     
Alamo River
 
LOE ID: 127339
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 25
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and results are as follows: 25 of 25 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 9 monitoring site(s) (723ARDP03, 723ARDP06, 723ARDP08, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARGRB1, 723ARINTL, 723NRRCD3)
Temporal Representation: The samples were collected between the dates of 2010-10-05 and 2013-10-23
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71978, Chloride
Region 7     
Alamo River
 
LOE ID: 127340
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and results are as follows: 1 of 1 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) (723ARGRB1)
Temporal Representation: The samples were collected between the dates of 2012-05-07 and 2012-05-07
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71978, Chloride
Region 7     
Alamo River
 
LOE ID: 33102
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 10
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 10 of the 12 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 stations 723ARGRB1 (Alamo River Outlet) and 723ARINTL (Alamo River at International Boundary).
Temporal Representation: Samples were collected on 10/26/2005, 5/1/2006, 5/7/2007, 10/23/2007, 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
68406
Region 7     
Alamo River
 
Pollutant: Chlorpyrifos
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the section 303(d) list under sections 2.2 and 4.1 of the Listing Policy.

Under these sections of the Policy, a minimum of one line of evidence is needed to assess listing status.

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

LOE 5468 was not used in the final use rating because it is replaced by LOE 46596.

This pollutant is a possible cause or contributor to toxicity.

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.
This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six of 16 total fraction, 22 of 33 dissolved fraction and 23 of 23 "not recorded" fraction water samples exceeded the California Department of Fish and Game (CDFG) criterion maximum concentration (CMC) for freshwater aquatic life use protection.

Sixteen of 21 total fraction water samples exceeded the California Department of Fish and Game (CDFG) criterion continuous concentration (CCC) for freshwater aquatic life use protection. Four samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

This exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.

This pollutant is a possible cause or contributor to toxicity.

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 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 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 125398
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 2 samples collected by DPR Surface Water Study 290 Name for Alamo River 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: Chironomus dilutus, for Survival, Chironomus dilutus, for Ash Free Dry Mass
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for DPR Surface Water Study 290 Name.
 
SWAMP Data: Non-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 2 stations. Monitoring site(s): ( 723IPGT59, 723IPRF29 )
Temporal Representation: The samples were collected between the dates of 2014-10-15 and 2014-10-15.
Environmental Conditions:
QAPP Information: A QAPP was not required for this data
QAPP Information Reference(s): This is a placeholder reference for data which does not require a QAPP.
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 127841
 
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 RWB7 TMDL data for Alamo River 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 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
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 3 station(s) (Station Code(s) 723ARDP06, 723ARDP10, 723ARGRB1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-11 to 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 35187
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Twelve samples total were collected. Two samples were detected at levels above the evaluation guideline resulting in 2 exceedances. Ten 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 Alamo River was collected at 2 monitoring sites [ Alamo River Outlet, Alamo River at International Boundary]
Temporal Representation: Data was collected over the time period 10/25/2005-10/28/2008.
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 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 2914
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 6
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Numeric data generated from 4 water samples collected as part of SWAMP and 7 samples collected by USGS. Six of these 11 samples exceeded the evaluation guideline (SWAMP, 2004; LeBlanc et al. 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: Department of Fish and Game guideline of 0.014 ug/L (Siepmann and Finlayson, 2000).
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Seven stations were sampled, all situated along the Alamo River from the international boundary with Mexico to the outlet (mouth) of the Alamo River into the Salton Sea.
Temporal Representation: Four samples taken during the spring (May) and the fall (October) of 2002. Seven samples collected in April 2003, and the guideline was exceeded in 5 of them.
Environmental Conditions: The Alamo River flows from Mexico through the Imperial Valley in the Salton Sea. Most of the water flowing through it comes from agricultural return flows.
QAPP Information: SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 125390
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 3
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 3 of the 7 samples collected by SWAMP RWB7 Monitoring for Alamo River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data 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 2 stations. Monitoring site(s): ( 723ARGRB1, 723ARINTL )
Temporal Representation: The samples were collected between the dates of 2011-05-10 and 2013-10-21.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 5271
 
Pollutant: Chlorpyrifos
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: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: One water quality sample was taken at 1 location along the river, collected on 4/01/1992. This sample did not exceed the CDFG Hazardous Assessment Criteria (USGS, 2007).
Data Reference: Data for organic and inorganic chemicals in water and sediment samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported on the National Water Information System (NWIS) Water Quality database. 1961-2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.02 ug/l for the protection of aquatic life uses (Siepmann and Finlayson, 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: A sample was collected at the following Alamo River location: USGS Station No. 10254730 near Niland, Ca.
Temporal Representation: One sample was collected on 4/01/1992.
Environmental Conditions:
QAPP Information: Assume samplers used standard USGS methods for sample collection (Wilde, variously dated). Assume analysts used standard analytical methods and quality assurance as described in (USGS, 2007).
QAPP Information Reference(s): Data for organic and inorganic chemicals in water and sediment samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported on the National Water Information System (NWIS) Water Quality database. 1961-2005.
  Field measurements: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A6. In United States Geological Survey (USGS). Variously dated. National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at http://pubs.water.usgs.gov/twri9A.
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 4801
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 6
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Fifteen water qualty samples were collected from three field events on 10/26/2004, 3/23/2005, and 6/07/2005, at five locations along the Alamo River. Of these total samples, 6 exceeded the CDFG Criteria. The exceedences were found in samples collected on 10/26/2004 and 3/23/2005 (CDPR, 2007).
Data Reference: Data for pesticides in water samples collected from waterbodies located in the Colorado River Basin-Region 7. Mar. 1993-Jun. 2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.02 ug/l (1 hr. ave.) for freshwater aquatic life use protection (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: Samples were collected at the following Alamo River sampling stations: Garst Road, Holville Main Drain at Highway 115, Malva Drain near Park, Vail Drain near Young, Verde Drain and Bonds Corner Road.
Temporal Representation: The samples were collected and analyzed from three field events on 10/26/2004, 3/23/2005, and 6/07/2005. The exceedences were found in samples collected from 10/26/2004 through 3/23/2005.
Environmental Conditions: Sampling was timed such that two of the sampling events took place during or immediately following periods of historically high pyrethroid use. Another sampling event took place during a period of relatively low historical pyrethroid use.
QAPP Information: Sampling methods described in Starner, 2004. Analysis performed by California Department of Food and Agriculture¿s Center for Analytical Chemistry, using quality control measures in accordance with Standard Operating Procedure QAQC001.00 (Segawa, 1995)
QAPP Information Reference(s): ¿Study 224. A Preliminary Assessment of Pyrethroid Contamination of Surface Waters and Bed Sediments in High Pyrethroid-Use Regions of California¿. California Department of Pesticide Regulation Environmental Monitoring Branch. Sacramento, CA.
  QAQC001.00 Standard Operating Procedures. Chemistry Laboratory Quality Control. California Department of Pesticide Regulation Environmental Hazards Assessment Branch. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 5468
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 35
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish tissue samples were generally collected from 6/1978 through 11/2000. Of these total samples, none exceeded the OEHHA Screening Value (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: Office of Environmental Health Hazard Assessment (OEHHA) Screening Value of 10000 ug/kg to protect human health when consuming fish (OEHHA, 1999).
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the years 1987. One tilapia whole fish composite sample was collected in the year 2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 35918
 
Pollutant: Chlorpyrifos
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 data for Alamo River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 1 monitoring site [ Alamo River Outlet - 723ARGRB1]
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 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 35426
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Chlorpyrifos.
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 for the Colorado River Basin).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 2 monitoring sites [ Alamo River Outlet - 723ARGRB1, Alamo River at International Boundary - 723ARINTL]
Temporal Representation: Data was collected over the time period 10/25/2005-4/21/2008.
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 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 125791
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB7 Monitoring data for Alamo River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 8 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: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 6 (Station Codes: 723ARDP06, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARGRB1, 723ARINTL).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-06 to 2011-10-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 4798
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 23
Number of Exceedances: 23
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Twenty-three water quality samples were generally collected once or twice a month from 3/15/1993 through 2/14/1994 at nine locations along the Alamo River. Of these total samples, 23 exceeded the CDFG Criteria. The exceedences were found in samples collected on 9/27/1993, 10/04/1993, 10/18/1993, 11/01/1993, 11/29/1993, and 12/13/1993 (CDPR, 2007).
Data Reference: Data for pesticides in water samples collected from waterbodies located in the Colorado River Basin-Region 7. Mar. 1993-Jun. 2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.02 ug/l (1 hr. ave.) for freshwater aquatic life use protection (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: Samples were collected at the following Alamo River sampling stations: at Outlet to the Salton Sea, Albright Road (Nectarine Drain Area), Shank Road (Magnolia Drain Area), downstream of Rose Drain, downstream of Holtville Main Drain, at the Harris Street Bridge, Worthington Road, Holtville WTP, Holtville, downstream of Verde Drain, and at the All American Canal intersection.
Temporal Representation: The samples were generally collected and analyzed once or twice a month from 3/15/1993 through 2/14/1994.The exceedences were found in samples collected from 9/27/1993 through 12/13/1993.
Environmental Conditions:
QAPP Information: Investigators used UCD ATL methods for sample collection, and USEPA methods for analysis. Lab analysis was done by the Dept. of Pesticide, Eureka Laboratories, and Agriculture and Priority Pollutants Laboratories (APPL). QA/QC is described in DiGiorgio, 1994.
QAPP Information Reference(s): "Colorado River Basin Toxicity Report, Draft Final, March 1993 through February 1994¿ prepared for V. de Vlaming and G. Starrett, SWRCB; prepared by, UC Davis Dept of Medicine and Epidemiology. Sacramento, CA. Interagency Agreement No. 0-149-250-0.
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 46596
 
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: 35
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish tissue samples were generally collected from 6/1978 through 11/2000. Of these total samples, none exceeded the OEHHA Screening Value (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: 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: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the years 1987. One tilapia whole fish composite sample was collected in the year 2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 45899
 
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: 5
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Chlorpyrifos. Nine composites were generated from three species: channel catfish, flathead catfish and Tilapia spp. Composites comprised of 2-3 fish for channel catfish and 1 fish for flathead catfish and Tilapia spp. Composites collected at the same time on the same day for the same species were averaged in accordance with the listing policy.
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 Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 4800
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 8
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Ten water quality samples were collected every few weeks from 8/28/1996 through 3/25/1997, at one location in the Alamo River. Of these total samples, 8 exceeded the CDFG Criteria. The exceedences were found in samples collected on 8/28/1996, 9/10/1996, 10/01/1996, 10/21/1996, 10/31/1996, 11/12/1996, 11/18/1996, and 3/05/1997 (CDPR, 2007).
Data Reference: Data for pesticides in water samples collected from waterbodies located in the Colorado River Basin-Region 7. Mar. 1993-Jun. 2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.02 ug/l (1 hr. ave.) for freshwater aquatic life use protection (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: Samples were collected from the Alamo River at the Garst Road bridge.
Temporal Representation: The samples were collected every few weeks from 8/28/1996 through 3/25/1997. The exceedences were found in samples collected from 8/28/1996 through 3/05/1997.
Environmental Conditions: The samples were collected every few weeks from August through November 1996 and from February through April 1997 to coincide with the pesticide application periods in the Imperial Valley (autumn and late winter/early spring) (Crepeau et al, 2002).
QAPP Information: Investigators used USGS QA/QC in sample collection and analysis. Lab analysis was done by the USGS California District Organic Chemistry Laboratory in Sacramento, California (Crepeau, 2002).
QAPP Information Reference(s): ¿Dissolved Pesticides in the Alamo River and the Salton Sea, California, 1996-97.¿ United States Geological Survey. Sacramento, CA. Open file report No. 02-232. http://water.usgs.gov/pubs/of/ofr02232/
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 125552
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Alamo River to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Chlorpyrifos .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 (Station Codes: 723ARGRB1).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-06 to 2013-10-21
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 4859
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 6
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Twenty-one water samples were taken at seven locations on the river. Ten water sample results could not be used in this assessment because the sample results were non-detect and the detection limit was above the criteria concentration. The eleven acceptable water quality samples were generally collected and analyzed twice a year from 5/06/2002 through 5/09/2005 at 7 locations along the Alamo River. Of these total samples, six exceeded the CDFG Criteria. The exceedences were found in samples collected on 10/02/2002, 4/08/2003, 4/09/2003, 4/11/2003, 11/04/2003, and 10/05/2004, from the Drop 6 location, Sinclair Road location near Calipatria, CA, and near the outlet to the Salton Sea location on Garst Road bridge (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: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.02 ug/l for the protection of aquatic life uses (Siepmann and Finlayson, 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, Drop 10 near Holtville, CA, at Harris Road near Imperial, CA, Drop 6A, Drop 6, at Sinclair Road near Calipatria, CA, and near the outlet to the Salton Sea on Garst Road bridge.
Temporal Representation: Twenty-one water samples were collected. Water samples were collected and analyzed biannually, usually in May and October, from 5/2002 through 5/2005 at the International Boundary, and Outlet to the Salton Sea. Two additional samples were collected from these two locations in 4/2003. The rest of the locations were sampled once in 4/2003.The exceedences were found in samples collected from 10/02/2002 through 10/05/2004.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 5181
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 8
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Twelve water quality samples were taken at 4 locations along the river, generally collected from 9/12/2006 through 4/17/2007. Of these total samples , 8 exceeded the CDFG Hazardous Assessment Criteria. The exceedences were found in samples collected on 10/14/2006, 10/16/2006, 10/17/2006, 11/13/2006, 2/13/2007, 3/12/2007, 3/14/2007, and 3/16/2007 from all four locations (Orlando et al, 2008).
Data Reference: "Pesticides in Water and Suspended Sediment of the Alamo and New Rivers, Imperial Valley/Salton Sea Basin, California, 2006-07". U.S. Geological Survey (USGS) Final Report prepared in cooperation with the California State Water Resources Control Board (SWRCB), delivered to the CRBRWQCB. Palm Desert, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.02 ug/l (1 hr. ave.) for freshwater aquatic life use protection (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: Samples were collected at the following Alamo River locations: at the Outlet to the Salton Sea near Niland, CA, near Calipatria, CA, at Harris Road near Imperial, CA, and at the International Boundary with Mexico.
Temporal Representation: Twelve samples were collected. Samples were generally collected from 9/12/2006 through 4/17/2007. Samples were collected from the outlet to the Salton Sea monthly from 9/2006 through 11/2006 and 2/2007 through 4/2007. The other three sites were sampled twice, once in 10/2006 and another time in 3/2007. The exceedences were found in samples collected from 10/14/2006 through 3/16/2007.
Environmental Conditions:
QAPP Information: Investigators used USGS methods for sample collection and analysis. Lab analysis was done by the USGS Laboratories in Sacramento, CA. All methods were approved by State Board QA officer (USGS, 2007b).
QAPP Information Reference(s): Quality Assurance Project Plan, Imperial Valley Pesticides TMDL Assessment Studies. Water Science Center. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 68406, Chlorpyrifos
Region 7     
Alamo River
 
LOE ID: 127973
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and the results are as follows: 8 of the 8 samples exceeded the water quality standard for Chlorpyrifos. Although a total of 13 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.014 ug/L (Siepmann and Finlayson 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Data was collected from 7 station(s): (Station Codes 723ARDP06, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARGRB1, 723ARINTL, 723NRRCD3).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-06 to 2013-10-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
78402
Region 7     
Alamo River
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the section 303(d) list under sections 2.2 and 4.5 of the Listing Policy. Under these sections of the Policy, a minimum of one line of evidence is needed to assess listing status.

Twenty-nine lines of evidence are available in the administrative record to assess this pollutant. This pollutant is a possible cause or contributor to toxicity.

LOE Nos. 2891 and 5378 are replaced by the LOE No. 46772, which is assessed based on the current evaluation guideline of 15 ppb for DDT in fish tissue.

Thirty-five of 35 total fraction fish tissue samples exceeded the OEHHA fish tissue guideline.

Seventeen of 23 fish fillet fraction fish tissue samples exceeded the OEHHA fish tissue guideline.

Fifty-seven of 76 water samples exceeded the CTR criteria for DDT.
These exceed the allowable frequency listed in Table 4.1 of the Listing Policy.

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.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Thirty-five of 35 total fraction fish tissue samples exceeded the OEHHA fish tissue guideline.

Seventeen of 23 fish fillet fraction fish tissue samples exceeded the OEHHA fish tissue guideline.

Fifty-seven of 76 water samples exceeded the CTR criteria for DDT.
These exceed the allowable frequency listed in Table 4.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be 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 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 45900
 
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: 5
Number of Exceedances: 5
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 5 of 5 samples exceed the criterion for DDT, Total. Nine composites were generated from three species: channel catfish, flathead catfish and Tilapia spp. Composites comprised of 2-3 fish for channel catfish and 1 fish for flathead catfish and Tilapia spp. Total DDT was calculated as the sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD. Composites collected at the same time on the same day for the same species were averaged in accordance with the listing policy.
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 Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 126647
 
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: 13
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and the results are as follows 7 of the 13 samples exceeded the water quality standard for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 7 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Common Carp each composed of 3 fish per composite, 3 composite(s) of Common Carp each composed of 5 fish per composite, 3 composite(s) of Tilapia spp. each composed of 5 fish per composite, 1 composite(s) of Common Carp each composed of 8 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite). Of these, 4 species (Common Carp, Flathead Catfish, Tilapia spp., Channel Catfish) exceeded the water quality standard.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total DDT in fish tissue is 15 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 4 station(s) with the station code(s): 723ARGRB1, 723ARDP3A, 723ARDP10, 723ARINTL.
Temporal Representation: Data for this line of evidence were collected between 2012-03-28 and 2014-12-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 126258
 
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: 5
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB7 TMDL data for Alamo River to determine beneficial use support and the results are as follows 5 of the 5 samples exceeded the water quality standard for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 4 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 4 fish per composite). Of these, 3 species (Common Carp, Channel Catfish, Flathead Catfish) exceeded the water quality standard.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total DDT in fish tissue is 15 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2011-04-21 and 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 126617
 
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: 13
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and the results are as follows 3 of the 13 samples exceeded the water quality standard for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 7 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Common Carp each composed of 3 fish per composite, 3 composite(s) of Common Carp each composed of 5 fish per composite, 3 composite(s) of Tilapia spp. each composed of 5 fish per composite, 1 composite(s) of Common Carp each composed of 8 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite). Of these, 2 species (Common Carp, Channel Catfish) exceeded the water quality standard.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum total DDT concentration of 1000 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data was collected from 4 station(s) with the station code(s): 723ARGRB1, 723ARDP3A, 723ARDP10, 723ARINTL.
Temporal Representation: Data for this line of evidence were collected between 2012-03-28 and 2014-12-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 45901
 
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: 5
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for DDT, Total. Nine composites were generated from three species: channel catfish, flathead catfish and Tilapia spp. Composites comprised of 2-3 fish for channel catfish and 1 fish for flathead catfish and Tilapia spp. Total DDT was calculated as the sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD. Composites collected at the same time on the same day for the same species were averaged in accordance with the listing policy.
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 Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 126680
 
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: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB7 TMDL data for Alamo River to determine beneficial use support and the results are as follows 1 of the 5 samples exceeded the water quality standard for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 4 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 4 fish per composite). Of these, 1 species (Channel Catfish) exceeded the water quality standard.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum total DDT concentration of 1000 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2011-04-21 and 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 125530
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
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 Alamo River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 6 (Station Codes: 723ARDP06, 723ARDP6A, 723ARINTL, 723ARGRB1, 723ARDP10, 723ARDP3A).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-05 to 2013-04-24
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 125906
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Alamo River to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 (Station Codes: 723ARGRB1).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-06 to 2013-10-21
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 29822
 
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: 10
Number of Exceedances:
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Ten water quality samples were collected and analyzed from 5/2002 through 5/2004 at two locations in the Alamo 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 fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, and near the outlet to the Salton Sea from Garst Road bridge.
Temporal Representation: Ten water samples were collected. Water samples were generally collected and analyzed biannually, in May and October, from 5/2002 through 5/2004 at the International Boundary and outlet to the Salton Sea locations.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 125550
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Alamo River to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 (Station Codes: 723ARGRB1).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-06 to 2013-10-21
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 32936
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of 8 samples collected for Sum DDT exceeded the evaluation guideline.
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. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (Colorado River Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: The Probable Effect Concentration for Sum DDT (o,p' + p,p') in freshwater sediments is 62.9 ug/kg.
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following stations: Alamo River at International Boundary - 723ARINTL, Alamo River Outlet - 723ARGRB1.
Temporal Representation: The samples were collected on 10/25/2005 - 4/21/2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 32957
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of 8 samples collected for Total DDTs exceeded the evaluation guideline.
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. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (Colorado River Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: The Probable Effect Concentration for Total DDTs (DDD + DDE + DDT) in freshwater sediments is 572 ug/kg.
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following stations: Alamo River at International Boundary - 723ARINTL, Alamo River Outlet - 723ARGRB1.
Temporal Representation: The samples were collected on 10/25/2005 - 4/21/2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 125501
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
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 Alamo River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline 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: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 6 (Station Codes: 723ARDP06, 723ARINTL, 723ARDP3A, 723ARGRB1, 723ARDP6A, 723ARDP10).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-05 to 2013-04-24
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 2891
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 11
Number of Exceedances: 11
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Eleven out of 11 samples exceeded. A total of 6 filet composite samples and 5 individual samples of carp and channel catfish were collected. Carp were collected in 1993-94, 2000, and 2002. Channel catfish were collected in 1993-94, 1996-98, and 2002. The guideline was exceeded in all samples. This addresses DDT and related pollutants (TSMP, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Colorado River Basin RWQCB Basin Plan: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: 100 ng/g (OEHHA Screening Value).
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Four stations along the Alamo River were sampled: upstream of Highway 78 crossing (Brawley), downstream of Sinclair Road (Calipatria), under the bridge at Highway 115 crossing (Holtville), and at the International Boundary to just downstream of Highway 98 (International Boundary).
Temporal Representation: Samples were collected annually 1993-94, 1996-98, 2000, and 2002.
Environmental Conditions:
QAPP Information: Toxic Substances Monitoring Program 1992-93 and 1994-95 Data Reports.

Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program, 1996-2000. Department of Fish and Game.

Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program, 2001-2002. Department of Fish and Game.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 5378
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 35
Number of Exceedances: 34
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish samples were generally collected from 6/1978 through 11/2000. Of these total samples, 30 fish fillet samples and 4 whole fish samples collected at four locations exceeded the OEHHA Fish Contaminant Goal. At the Calipatria location the exceedances were found in ;12 channel catfish fillet composite samples collected on 6/21/1978, 3/12/1979, 5/08/1980, 5/23/1981, 4/22/1982, 6/13/1983, 5/23/1984, 9/17/1985, 9/30/1987, 11/01/1996, 11/20/1997, and 11/11/1998; 2 channel catfish single fish fillet samples collected on 10/28/1989, and 10/27/1994: 8 carp fillet composite samples collected on 5/23/1981, 4/22/1982, 6/13/1983, 5/23/1984, 9/17/1985, 11/18/1988, 8/03/1990, and 9/29/1993; 3 carp single fish fillet samples collected on 6/21/1978, 10/27/1994, and 11/07/2000; 1 spiny soft shelled turtle fillet composite sample collected on 9/20/1992, and; 1 red swampy crayfish whole fish composite sample collected on 3/12/1979. At the Brawley location 1 exceedance was found in 1 channel catfish fillet composite sample collected on 9/30/1993. At the Holtville location 1 exceedance was found in 1 carp single fish fillet sample collected on 9/30/1993. At the International Boundary location the exceedances were found in; 1 carp fillet composite sample collected on 11/20/1998, 1 largemouth bass fillet composite sample collected on 11/15/1985; 1 tilapia whole fish composite sample on 11/07/2000; 1 redshiner whole fish composite collected on 11/15/1985, and; 1 mosquitofish whole fish composite sample collected on 9/02/1987 (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: Office of Environmental Health Hazard Assessment (OEHHA) Fish Contaminant Goal of 21 ug/kg to protect human health when consuming fish (OEHHA, 2008).
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000. The exceedances were found in samples collected from 6/21/1978 through 11/07/2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 46772
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 35
Number of Exceedances: 35
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish samples were generally collected from 6/1978 through 11/2000. Of these total samples, 30 fish fillet samples and 4 whole fish samples collected at four locations exceeded the OEHHA Fish Contaminant Goal. At the Calipatria location the exceedances were found in ;12 channel catfish fillet composite samples collected on 6/21/1978, 3/12/1979, 5/08/1980, 5/23/1981, 4/22/1982, 6/13/1983, 5/23/1984, 9/17/1985, 9/30/1987, 11/01/1996, 11/20/1997, and 11/11/1998; 2 channel catfish single fish fillet samples collected on 10/28/1989, and 10/27/1994: 1 red swamp crayfish sample collected on 5/8/1980; 8 carp fillet composite samples collected on 5/23/1981, 4/22/1982, 6/13/1983, 5/23/1984, 9/17/1985, 11/18/1988, 8/03/1990, and 9/29/1993; 3 carp single fish fillet samples collected on 6/21/1978, 10/27/1994, and 11/07/2000; 1 spiny soft shelled turtle fillet composite sample collected on 9/20/1992, and; 1 red swampy crayfish whole fish composite sample collected on 3/12/1979. At the Brawley location 1 exceedance was found in 1 channel catfish fillet composite sample collected on 9/30/1993. At the Holtville location 1 exceedance was found in 1 carp single fish fillet sample collected on 9/30/1993. At the International Boundary location the exceedances were found in; 1 carp fillet composite sample collected on 11/20/1998, 1 largemouth bass fillet composite sample collected on 11/15/1985; 1 tilapia whole fish composite sample on 11/07/2000; 1 redshiner whole fish composite collected on 11/15/1985, and; 1 mosquitofish whole fish composite sample collected on 9/02/1987 (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000. The exceedances were found in samples collected from 6/21/1978 through 11/07/2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 5584
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 35
Number of Exceedances: 24
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish tissue samples were generally collected from 6/1978 through 11/2000. Of these total samples, 22 fish fillet samples and 2 whole fish samples collected at two locations exceeded the NAS tissue guideline. At the Calipatria location the exceedances were found in ;10 channel catfish fillet composite samples collected on 3/12/1979, 5/08/1980, 5/23/1981, 4/22/1982, 6/13/1983, 5/23/1984, 9/17/1985, 9/30/1987, 11/01/1996, and 11/20/1997; 8 carp fillet composite samples collected on 5/23/1981, 4/22/1982, 6/13/1983, 5/23/1984, 9/17/1985, 11/18/1988, 8/03/1990, and 9/29/1993, and; 3 carp single fish fillet samples collected on 6/21/1978, 10/27/1994, and 11/07/2000. At the International Boundary location the exceedances were found in; 1 carp fillet composite sample collected on 11/20/1998; 1 redshiner whole fish composite sample collected on 11/15/1985, and; 1 mosquitofish whole fish composite sample collected on 9/02/1987 (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: National Academy of Science (NAS) tissue guideline of 1000 ug/kg for the protection of aquatic life uses (NAS, 1973).
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Samples were collected from the Alamo River at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish fillet samples of channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000. The exceedances were found in samples collected from 6/21/1978 through 11/07/2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 5183
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Twelve water quality samples were taken at 4 locations along the river, generally collected from 9/12/2006 through 4/17/2007. Of these total samples , none exceeded the CTR Criteria (Orlando et al, 2008).
Data Reference: "Pesticides in Water and Suspended Sediment of the Alamo and New Rivers, Imperial Valley/Salton Sea Basin, California, 2006-07". U.S. Geological Survey (USGS) Final Report prepared in cooperation with the California State Water Resources Control Board (SWRCB), delivered to the CRBRWQCB. Palm Desert, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) Criterion Maximum Concentration (CMC) 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 at the following Alamo River locations: at the Outlet to the Salton Sea near Niland, CA, near Calipatria, CA, at Harris Road near Imperial, CA, and at the International Boundary with Mexico.
Temporal Representation: Twelve samples were collected. Samples were generally collected from 9/12/2006 through 4/17/2007. Samples were collected from the outlet to the Salton Sea monthly from 9/06 through 11/06 and 2/07 through 4/07. The other three sites were sampled twice, once in 10/2006 and another time in 3/2007.
Environmental Conditions:
QAPP Information: Investigators used USGS methods for sample collection and analysis. Lab analysis was done by the USGS Laboratories in Sacramento, CA. All methods were approved by State Board QA officer (USGS, 2007b).
QAPP Information Reference(s): Quality Assurance Project Plan, Imperial Valley Pesticides TMDL Assessment Studies. Water Science Center. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 5005
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Nineteen water quality samples were generally collected and analyzed biannually from 5/2002 through 5/2005 at 7 locations along the Alamo 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) 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 from the following Alamo River locations: at the International Boundary, Drop 10 near Holtville, CA, at Harris Road near Imperial, CA, Drop 6A, Drop 6, at Sinclair Road near Calipatria, CA,and near the outlet to the Salton Sea from Garst Road bridge.
Temporal Representation: Ninteen water samples were collected. Water samples were generally collected and analyzed biannually, in May and October, from 5/2002 through 5/2005 at the International Boundary and outlet to the Salton Sea locations. The rest of the locations were sampled in April 2003 only.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 2890
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Samples were collected by the RWQCB on 6/21/2001 at 7 different stations. All samples were non-detects, with a detection limit of 0.1 ppb. Samples were also collected by the RWQCB on 4/15/2003 at 7 different stations. All samples were non-detects, with a detection limit of 0.018 ppb. Therefore, there were no exceedances of the total 14 samples (CRBRWQCB, 2004c).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: CTR: freshwater acute maximum = 1.1 ppb for 4,4'DDT and freshwater chronic maximum = 0.001 ppb for 4,4'DDT as a 4-day average.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at the following Alamo River sampling stations: AR-B (at the International Boundary), AR-D10 (Lower Alamo River drainshed, at Drop Structure #10), AR-D8 (Central Drain drainshed, at Drop Structure #8), AR-D6A (Holtville Main Drain drainshed, at Drop Structure #6A), AR-D6 (Rose Drain drainshed, at Drop Structure #6), AR-D3 (Central Alamo River drainshed, at Drop Structure #3), and at AR-GRB.
Temporal Representation: All samples were collected on 4/15/2003 and 6/21/2001.
Environmental Conditions:
QAPP Information: Used RWQCB QA/QC in sample collection. Lab analysis was done by North Coast Labs.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 32394
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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: The one sample collected was 23.067 ug/kg and did not exceeded the evaluation guideline.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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 (Colorado River Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: The Probable Effect Concentration for Total DDTs in freshwater sediments is 572 ug/kg.
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station: Alamo River Outlet (723ARGRB1).
Temporal Representation: One sample was collected on 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
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 32395
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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: The one sample collected was 2.032 ug/kg and did not exceeded the evaluation guideline.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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 (Colorado River Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: The Probable Effect Concentration for Sum DDT in freshwater sediments is 62.9 ug/kg.
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station: Alamo River Outlet (723ARGRB1).
Temporal Representation: One sample was collected on 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
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 5199
 
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: 57
Number of Exceedances: 57
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Eighty-seven water samples were taken at 2 locations on the river. Thirty water sample results could not be used in the assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the sample results were zero and the detection limit could not be determined. The 57 acceptable water quality samples were generally collected from 8/1969 through 4/1992. Of these total samples, 57 exceeded the CTR Criteria. The exceedences were found in samples collected from 8/13/1969 through 4/01/1992 at 2 locations (USGS, 2007).
Data Reference: Data for organic and inorganic chemicals in water and sediment samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported on the National Water Information System (NWIS) Water Quality database. 1961-2005.
  Field measurements: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A6. In United States Geological Survey (USGS). Variously dated. National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at http://pubs.water.usgs.gov/twri9A.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) Criteria of 0.00059 ug/l for the protection of human health when consuming organisms from aquatic systems (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 at the following Alamo River locations: USGS Station No. 10254670 located at Drop 3 near Calipatria, Ca, and USGS Station No. 10254730 near Niland, Ca.
Temporal Representation: Eighty-seven samples were collected. Samples were generally collected from 8/1969 through 4/1992. Eight samples were collected in 1969, 78 samples were collected from 1970-1979, no samples were collected from 1980-1989, and 1 sample was collected from 1990-1999. The exceedences were found in samples collected from 8/13/1969 through 4/01/1992.
Environmental Conditions:
QAPP Information: Assume samplers used standard USGS methods for sample collection (Wilde, variously dated). Assume analysts used standard analytical methods and quality assurance as described in (USGS, 2007).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 128547
 
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: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB7 TMDL data for Alamo River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for DDT (Dichlorodiphenyltrichloroethane).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
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 2 monitoring site(s) (723ARDP10, 723ARGRB1)
Temporal Representation: The samples were collected between the dates of 2011-02-11 and 2011-04-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 127136
 
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: 16
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 Alamo River to determine beneficial use support and results are as follows: 0 of 16 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 6 monitoring site(s) (723ARINTL, 723ARGRB1, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARDP06)
Temporal Representation: The samples were collected between the dates of 2010-10-05 and 2012-10-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 34523
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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: 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 723ARGRB1 (Alamo River Outlet) and 723ARINTL (Alamo River at International Boundary).
Temporal Representation: Samples collected between 10/25/2005 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 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 127137
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
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 Alamo River to determine beneficial use support and results are as follows: 0 of 16 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 6 monitoring site(s) (723ARINTL, 723ARGRB1, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARDP06)
Temporal Representation: The samples were collected between the dates of 2010-10-05 and 2012-10-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 5190
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 58
Number of Exceedances: 1
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Eighty-seven water samples were taken at 2 locations on the river. Twenty-eight water sample results could not be used in the assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the sample results were zero and the detection limit could not be determined. The 58 acceptable water quality samples were collected from 8/1969 through 4/92 at 2 locations in the river. Of these total samples , one exceeded the CTR Criteria. The exceedence was found in a sample collected on 11/19/1975 at Drop 3 near Calipatria, CA (USGS, 2007).
Data Reference: Data for organic and inorganic chemicals in water and sediment samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported on the National Water Information System (NWIS) Water Quality database. 1961-2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) Criterion Maximum Concentration (CMC) of 1.1 ug/l p,p'-DDT 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 at the following Alamo River locations: USGS Station No. 10254730 located near Niland, Ca., USGS Station No. 10254670 located at Drop 3 near Calipatria, Ca.
Temporal Representation: Eighty-seven samples were collected. Samples were generally collected from 8/1969 through 4/1992. Eight samples were collected in 1969, 78 samples were collected from 1970-1979, no samples were collected from 1980-1989, and 1 sample was collected from 1990-1992. The exceedence was from a sample collected on 11/19/1975.
Environmental Conditions:
QAPP Information: Assume samplers used standard USGS methods for sample collection (Wilde, variously dated). Assume analysts used standard analytical methods and quality assurance as described in (USGS, 2007).
QAPP Information Reference(s): Data for organic and inorganic chemicals in water and sediment samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported on the National Water Information System (NWIS) Water Quality database. 1961-2005.
  Field measurements: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A6. In United States Geological Survey (USGS). Variously dated. National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at http://pubs.water.usgs.gov/twri9A.
 
Line of Evidence (LOE) for Decision ID 78402, DDT (Dichlorodiphenyltrichloroethane)
Region 7     
Alamo River
 
LOE ID: 127303
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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 RWB7 TMDL data for Alamo River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for DDT (Dichlorodiphenyltrichloroethane).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
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 2 monitoring site(s) (723ARDP10, 723ARGRB1)
Temporal Representation: The samples were collected between the dates of 2011-02-11 and 2011-04-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
71434
Region 7     
Alamo River
 
Pollutant: Diazinon
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the section 303(d) list under sections 2.2 and 4.1 of the Listing Policy.

Under these sections of the Policy, a minimum of one line of evidence is needed to assess listing status.

Eighteen lines of evidence are available in the administrative record to assess this pollutant. LOE No. 5469 is not included in final use rating as it is reassessed based on the current evaluation guideline (OEHHA Fish Contaminant Goal) and replaced by the LOE No. 46597.

Thirty-one of 75 total fraction, ten of 42 dissolved fraction, and 34 of 84 ""not recorded"" fraction water samples exceeded the California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.16 ug/l.

Three of 38 water samples exceeded the freshwater chronic value expressed as a continuous concentration of 0.1 ug/L.

This pollutant is a possible cause or contributor to toxicity.

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.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Thirty-one of 75 total fraction, ten of 42 dissolved fraction, and 34 of 84 ""not recorded"" fraction water samples exceeded the California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.16 ug/l.

Three of 38 water samples exceeded the freshwater chronic value expressed as a continuous concentration of 0.1 ug/L.

These exceed the allowable frequency listed in Table 4.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be 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 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 125907
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Alamo River to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 (Station Codes: 723ARGRB1).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-06 to 2013-10-21
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 5469
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 35
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish samples were generally collected from 6/1978 through 11/2000. Of these total samples, none exceeded the OEHHA Screening Value (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: Office of Environmental Health Hazard Assessment (OEHHA) Screening Value of 300 ug/kg to protect human health when consuming fish (OEHHA, 1999).
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Calipatria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples of channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 125764
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
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 Alamo River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 6 (Station Codes: 723ARDP06, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARGRB1, 723ARINTL).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-05 to 2013-04-24
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 35507
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Diazinon.
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 for the Colorado River Basin).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 2 monitoring sites [ Alamo River Outlet - 723ARGRB1, Alamo River at International Boundary - 723ARINTL]
Temporal Representation: Data was collected over the time period 10/25/2005-4/21/2008.
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 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 4802
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 84
Number of Exceedances: 34
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Eighty-four water quality samples were generally collected and analyzed once or twice a month from 3/15/1993 through 2/14/1994 at nine locations along the Alamo River. Of these total samples, 34 exceeded the CDFG Criteria. The exceedences were found in samples collected on 3/15/1993, 6/21/1993, 9/27/1993, 10/04/1993, 10/18/1993, 11/01/1993, 11/29/1993, 12/13/1993, 1/24/1994, and 2/14/1994 (CDPR, 2007).
Data Reference: Data for pesticides in water samples collected from waterbodies located in the Colorado River Basin-Region 7. Mar. 1993-Jun. 2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.16 ug/l (1 hr. ave.) for freshwater aquatic life use protection (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: Samples were collected at the following Alamo River sampling stations: at Outlet to the Salton Sea, Albright Road (Nectarine Drain Area), Shank Road (Magnolia Drain Area), downstream of Rose Drain, downstream of Holtville Main Drain, at the Harris Street Bridge, Worthington Road, Holtville WTP, Holtville, downstream of Verde Drain, and at the All American Canal intersection.
Temporal Representation: Eighty-four water samples were collected. The samples were generally collected and analyzed once or twice a month from 3/15/1993 through 2/14/1994. The exceedences were found in samples collected from 3/15/1993 through 2/14/1994.
Environmental Conditions:
QAPP Information: Investigators used UCD ATL methods for sample collection, and USEPA methods for analysis. Lab analysis was done by the Dept. of Pesticide, Eureka Laboratories, and Agriculture and Priority Pollutants Laboratories (APPL). QA/QC is described in DiGiorgio, 1994.
QAPP Information Reference(s): "Colorado River Basin Toxicity Report, Draft Final, March 1993 through February 1994¿ prepared for V. de Vlaming and G. Starrett, SWRCB; prepared by, UC Davis Dept of Medicine and Epidemiology. Sacramento, CA. Interagency Agreement No. 0-149-250-0.
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 46597
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 35
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish samples were generally collected from 6/1978 through 11/2000. Of these total samples, none exceeded the OEHHA Fish Contaminant Goal.
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: The modified OEHHA Fish Contaminant Goal for diazinon in fish tissue is 1,500 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets.
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
  Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Calipatria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples of channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 46013
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Diazinon. Nine composites were generated from three species: channel catfish, flathead catfish and Tilapia spp. Composites comprised of 2-3 fish for channel catfish and 1 fish for flathead catfish and Tilapia spp. Composites collected at the same time on the same day for the same species were averaged in accordance with the listing policy.
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 diazinon in fish tissue is 1,500 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets.
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
  Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 4803
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 4
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Ten water quality samples were collected every few weeks from 8/28/1996 through 3/25/1997 at one location on the Alamo River. Of these total samples, 4 exceeded the CDFG Criteria. The exceedences were found in samples collected from 10/01/1996, 10/21/1996, 10/31/1996, and 11/12/1996 (CDPR, 2007).
Data Reference: Data for pesticides in water samples collected from waterbodies located in the Colorado River Basin-Region 7. Mar. 1993-Jun. 2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.16 ug/l (1 hr. ave.) for freshwater aquatic life use protection (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: Samples were collected from the Alamo River at Garst Road bridge.
Temporal Representation: Ten water samples were collected. The samples were collected every few weeks from 8/28/1996 through 3/25/1997. The exceedences were found in samples collected from 10/01/1996 through 11/12/1996.
Environmental Conditions: The samples were collected every few weeks from August through November 1996 and from February through April 1997 to coincide with the pesticide application periods in the Imperial Valley (autumn and late winter/early spring) (Crepeau et al, 2002).
QAPP Information: Investigators used USGS QA/QC in sample collection and analysis. Lab analysis was done by the USGS California District Organic Chemistry Laboratory in Sacramento, California (Crepeau, 2002)
QAPP Information Reference(s): ¿Dissolved Pesticides in the Alamo River and the Salton Sea, California, 1996-97.¿ United States Geological Survey. Sacramento, CA. Open file report No. 02-232. http://water.usgs.gov/pubs/of/ofr02232/
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 5185
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 4
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Twelve water quality samples were taken at 4 locations along the river, generally collected from 9/12/2006 through 4/17/2007. Of these total samples , 4 exceeded the CDFG Hazardous Assessment Criteria. The exceedences were found in samples collected on 10/14/2006, 10/16/2006, 10/17/2006, and 11/13/2006 from three locations, at the Outlet to the Salton Sea near Niland, CA, near Calipatria, CA, and at Harris Road near Imperial, CA (Orlando et al, 2008).
Data Reference: "Pesticides in Water and Suspended Sediment of the Alamo and New Rivers, Imperial Valley/Salton Sea Basin, California, 2006-07". U.S. Geological Survey (USGS) Final Report prepared in cooperation with the California State Water Resources Control Board (SWRCB), delivered to the CRBRWQCB. Palm Desert, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.16 ug/l (1 hr. ave.) for freshwater aquatic life use protection (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: Samples were collected at the following Alamo River locations: at the Outlet to the Salton Sea near Niland, CA, near Calipatria, CA, at Harris Road near Imperial, CA, and at the International Boundary with Mexico.
Temporal Representation: Twelve water samples were collected. Samples were collected from the outlet to the Salton Sea monthly from 9/06 through 11/07 and 2/07 through 4/07. The other sites were sampled only twice, once in 10/2006 and another time in 3/2007. The exceedences were found in samples collected from 10/14/2006 through 11/13/2006.
Environmental Conditions:
QAPP Information: Investigators used USGS methods for sample collection and analysis. Lab analysis was done by the USGS Laboratories in Sacramento, CA. All methods were approved by State Board QA officer (USGS, 2007b).
QAPP Information Reference(s): Quality Assurance Project Plan, Imperial Valley Pesticides TMDL Assessment Studies. Water Science Center. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 4867
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Twenty water quality samples were collected and analyzed biannually from 5/2002 through 5/2005 at 7 locations along the Alamo River. Of these total samples , 2 exceeded the CDFG Criteria. The exceedences were found in samples collected on 10/02/2002, and 10/05/2004 from the outlet to the Salton Sea location (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: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.16 ug/l for the protection of aquatic life uses (Siepmann and Finlayson, 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, Drop 10 near Holtville, CA, at Harris Road near Imperial, CA, Drop 6A, Drop 6, at Sinclair Road near Calipatria, CA,and near the outlet to the Salton Sea on Garst Road bridge.
Temporal Representation: Twenty water samples were collected. Water samples were generally collected and analyzed biannually, usually in May and October, from 5/2002 through 5/2005 at the International Boundary, and Outlet to the Salton Sea. Two additional samples were collected in 4/2003 from these two locations. The rest of the locations were sampled once in 4/2003.The exceedences were found in samples collected from 10/02/2002 through 10/05/2004.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 125398
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 2 samples collected by DPR Surface Water Study 290 Name for Alamo River 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: Chironomus dilutus, for Survival, Chironomus dilutus, for Ash Free Dry Mass
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for DPR Surface Water Study 290 Name.
 
SWAMP Data: Non-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 2 stations. Monitoring site(s): ( 723IPGT59, 723IPRF29 )
Temporal Representation: The samples were collected between the dates of 2014-10-15 and 2014-10-15.
Environmental Conditions:
QAPP Information: A QAPP was not required for this data
QAPP Information Reference(s): This is a placeholder reference for data which does not require a QAPP.
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 125390
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 3
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 3 of the 7 samples collected by SWAMP RWB7 Monitoring for Alamo River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data 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 2 stations. Monitoring site(s): ( 723ARGRB1, 723ARINTL )
Temporal Representation: The samples were collected between the dates of 2011-05-10 and 2013-10-21.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 127623
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
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 Alamo River to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality standard for Diazinon.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 7 monitoring site(s) (723ARDP06, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARGRB1, 723ARINTL, 723NRRCD3)
Temporal Representation: The samples were collected between the dates of 2010-10-05 and 2013-10-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 35193
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 3 of 12 samples exceed the criterion for Diazinon.
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 chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 2 monitoring sites [ Alamo River Outlet, Alamo River at International Boundary]
Temporal Representation: Data was collected over the time period 10/25/2005-10/28/2008.
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 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 127131
 
Pollutant: Diazinon
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 RWB7 TMDL data for Alamo River to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality standard for Diazinon.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 3 monitoring site(s) (723ARDP06, 723ARDP10, 723ARGRB1)
Temporal Representation: The samples were collected between the dates of 2011-02-11 and 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 4804
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 3
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Fifteen water quality samples were collected from three field events on 10/26/2004, 3/23/2005, and 6/07/2005 at five locations along the Alamo River. Of these total samples, 3 exceeded the CDFG Criteria. All three exceedences were found in samples collected on 10/26/04 (CDPR, 2007).
Data Reference: Data for pesticides in water samples collected from waterbodies located in the Colorado River Basin-Region 7. Mar. 1993-Jun. 2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.16 ug/l (1 hr. ave.) for freshwater aquatic life use protection (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: Samples were collected at the following Alamo River sampling stations: Garst Road, Holtville Main Drain at Highway 115, Malva Drain near Park, Vail Drain near Young, Verde Drain and Bonds Corner Road.
Temporal Representation: Fifteen water samples were collected. The samples were collected and analyzed from three field events on 10/26/2004, 3/23/2005, and 6/07/2005. All three exceedences were found in samples collected on 10/26/04.
Environmental Conditions: Sampling was timed such that two of the sampling events took place during or immediately following periods of historically high pyrethroid use. Another sampling event took place during a period of relatively low historical pyrethroid use.
QAPP Information: Sampling methods described in Starner, 2004. Analysis performed by California Department of Food and Agriculture¿s Center for Analytical Chemistry using quality control measures in accordance with Standard Operating Procedure QAQC001.00 (Segawa, 1995).
QAPP Information Reference(s): ¿Study 224. A Preliminary Assessment of Pyrethroid Contamination of Surface Waters and Bed Sediments in High Pyrethroid-Use Regions of California¿. California Department of Pesticide Regulation Environmental Monitoring Branch. Sacramento, CA.
  QAQC001.00 Standard Operating Procedures. Chemistry Laboratory Quality Control. California Department of Pesticide Regulation Environmental Hazards Assessment Branch. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 5205
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 60
Number of Exceedances: 28
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Sixty-nine water samples were taken at 2 locations on the river. Nine water sample results could not be used in the assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the sample results were zero and the detection limit could not be determined. The 60 acceptable water quality samples were generally collected from 1/1971 through 4/1992. Of these total samples, 28 exceeded the CDFG Hazardous Assessment Criteria (USGS, 2007). The exceedences were found in samples collected from 1/18/1971, 10/07/1975, 11/19/1975, 1/29/1976, 2/18/1976, 3/17/1976, 6/02/1976, 9/22/1976, 3/22/1977, 4/19/1977, 9/13/1977, 10/20/1977, 11/08/1977, 1/25/1978/ 3/22/.1978/ 4/26/1978/ and 9/27/1978 from the two locations. (USGS, 2007).
Data Reference: Data for organic and inorganic chemicals in water and sediment samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported on the National Water Information System (NWIS) Water Quality database. 1961-2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.16 ug/l for the protection of aquatic life uses (Siepmann and Finlayson, 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected at the following Alamo River locations: USGS Station No. 10254670 located at Drop 3 near Calipatria, Ca, and USGS Station No. 10254730 near Niland, Ca.
Temporal Representation: Sixty-nine samples were collected. Samples were generally collected from 1/1971 through 4/1992. Twenty-six samples were collected from 1971 to 1979, 41 from 1980 to 1989, and 1 in 1992. The exceedences were found in samples collected from 1/18/1971 through 9/27/1978.
Environmental Conditions:
QAPP Information: Assume samplers used standard USGS methods for sample collection (Wilde, variously dated). Assume analysts used standard analytical methods and quality assurance as described in (USGS, 2007).
QAPP Information Reference(s): Data for organic and inorganic chemicals in water and sediment samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported on the National Water Information System (NWIS) Water Quality database. 1961-2005.
  Field measurements: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A6. In United States Geological Survey (USGS). Variously dated. National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at http://pubs.water.usgs.gov/twri9A.
 
Line of Evidence (LOE) for Decision ID 71434, Diazinon
Region 7     
Alamo River
 
LOE ID: 35937
 
Pollutant: Diazinon
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 data for Alamo River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the Colorado River Basin).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 1 monitoring site [ Alamo River Outlet - 723ARGRB1]
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
78414
Region 7     
Alamo River
 
Pollutant: Dieldrin
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the section 303(d) list under sections 2.2, 4.1 and 4.5 of the Listing Policy.

Under these sections of the Policy, a minimum of one line of evidence is needed to assess listing status.

Twenty-seven lines of evidence are available in the administrative record to assess this pollutant.

LOE No. 5379 is replaced by the LOE No. 46598 with a new evaluation guideline, and is not inclued in final use rating.

LOE No. 2883 from 2006 is not icluded in the final use rating because it contains false information about the data. The LOE described that all 14 water samples were non-detects and did not exceed either of acute or chronic criteria (Data Used to Assess Water Quality), but it shows contradictory exceedances (Number of Exceedences) with14 out of 14 exceedances. Staff could not track the original data to verify whether all 14 water samples were non-detect or all were exceeded. Thus, LOE No. 2883 is not included in the final use rating.

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.

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. Seventeen of 17 fish fillet fraction fish tissue samples exceed the OEHHA FCG to protect human health when consuming fish.
Thirty of 30 total fraction fish tissue samples exceed the OEHHA FCG to protect human health when consuming fish.
One of 30 total fraction fish tissue samples exceed the National Academy of Science (NAS) tissue guideline for the protection of aquatic life uses.

Fifty-eight of 58 total fraction and three dissolved fraction water samples exceeded the California Toxics Rule (CTR) Criteria for the protection of human health when consuming organisms from aquatic systems

These exceed the allowable frequency listed in Table 4.1 of the Listing Policy.

This pollutant is a possible cause or contributor to toxicity.

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 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 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 127154
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
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 Alamo River to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality standard for Dieldrin.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: 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 7 monitoring site(s) (723ARDP06, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARGRB1, 723ARINTL, 723NRRCD3)
Temporal Representation: The samples were collected between the dates of 2010-10-05 and 2013-10-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 35304
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Dieldrin.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: 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 Alamo River was collected at 2 monitoring sites [ Alamo River Outlet, Alamo River at International Boundary]
Temporal Representation: Data was collected over the time period 10/25/2005-10/28/2008.
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 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 125381
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 7
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 7 of the 11 samples collected by SWAMP RWB7 Monitoring for Alamo River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: 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 6 stations. Monitoring site(s): ( 723ARDP06, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARGRB1, 723ARINTL )
Temporal Representation: The samples were collected between the dates of 2010-10-05 and 2013-04-22.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 125387
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 3
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 3 of the 4 samples collected by SWAMP Stream Pollution Trends for Alamo River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends.
 
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): ( 723ARGRB1 )
Temporal Representation: The samples were collected between the dates of 2010-10-06 and 2014-10-22.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 125390
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 3
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 3 of the 7 samples collected by SWAMP RWB7 Monitoring for Alamo River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data 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 2 stations. Monitoring site(s): ( 723ARGRB1, 723ARINTL )
Temporal Representation: The samples were collected between the dates of 2011-05-10 and 2013-10-21.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 125398
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 2 samples collected by DPR Surface Water Study 290 Name for Alamo River 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: Chironomus dilutus, for Survival, Chironomus dilutus, for Ash Free Dry Mass
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for DPR Surface Water Study 290 Name.
 
SWAMP Data: Non-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 2 stations. Monitoring site(s): ( 723IPGT59, 723IPRF29 )
Temporal Representation: The samples were collected between the dates of 2014-10-15 and 2014-10-15.
Environmental Conditions:
QAPP Information: A QAPP was not required for this data
QAPP Information Reference(s): This is a placeholder reference for data which does not require a QAPP.
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 5006
 
Pollutant: Aldrin | Chlordane | 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: 14
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Fourteen water quality samples were collected and analyzed biannually from 5/2002 through 5/2005 at 2 locations along the Alamo 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, 0.22 ug/l beta-Endosulfan, 2.4 ug/l Chlordane, 0.24 ug/l Dieldrin, 0.086 ug/l Endrin, 0.52 ug/l Heptachlor, and 0.52 ug/l 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 from the following Alamo River locations: at the International Boundary, and near the outlet to the Salton Sea from Garst Road bridge.
Temporal Representation: Fourteen water samples were collected. Water samples were collected and analyzed biannually, in May and October, from 5/2002 through 5/2005.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 5105
 
Pollutant: Benzo(a)anthracene | Chrysene (C1-C4) | Dieldrin | Endrin | Fluoranthene | Fluorene | Lindane/gamma Hexachlorocyclohexane (gamma-HCH) | Naphthalene | PCBs (Polychlorinated biphenyls) | Phenanthrene | Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Fourteen sediment quality samples were collected and analyzed biannually from 5/2002 through 5/2005 at 2 locations in the along the Alamo River. Of these total samples, none exceeded the PEC (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: Consensus Based Sediment Quality Guideline Probable Effects Concentrations (PECs) for the protection of freshwater organisms to toxic effects were used for the following constituents: 1050 ug/kg Benz[a]anthrazene, 1290 ug/kg Chrysene, 61.8 ug/g Dieldrin, 207 ug/kg Endrin, 2230 ug/kg Fluoranthene, 536 ug/kg Fluorene, 4.99 ug/kg Lindane/Hexachlorocyclohexane (HCH), 561 ug/kg Naphthalene, 676 ug/kg PCBs (Polychlorinated biphenyls), 1170 ug/kg Phenanthrene , 1520 ug/kg Pyrene (Macdonald et al, 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, and near the outlet to the Salton Sea on Garst Road.
Temporal Representation: Fourteen sediment samples were collected. Sediment samples were generally collected and analyzed biannually, in May and October, from 5/2002 through 5/2005.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 4869
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Fourteen water samples were taken at two locations on the river. Eleven water sample results could not be used in this assessment because the sample results were non-detect and the detection limit was above the criteria concentration. The three acceptible water quality samples were collected on and analyzed biannually from 5/06/2002, 11/04/2003, and 5/04/2004 at the outlet to the Salton Sea location. All three 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) Criteria of 0.00014 ug/l for the protection of human health when consuming organisms from aquatic systems (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 from the following Alamo River locations: at the International Boundary, and near the outlet to the Salton Sea on Garst Road bridge.
Temporal Representation: Fourteen water samples were collected. Water samples were collected and analyzed biannually from 5/2002 through 5/2005 at the International Boundary and outlet to the Salton Sea locations. Samples were usually collected in May and October.The exceedences were found in samples collected from 5/06/2002 through 5/03/2004. in samples collected from 5/06/2002 through 5/03/2004.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 46014
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 5 of 5 samples exceed the criterion for Dieldrin. Nine composites were generated from three species: channel catfish, flathead catfish and Tilapia spp. Composites comprised of 2-3 fish for channel catfish and 1 fish for flathead catfish and Tilapia spp. Composites collected at the same time on the same day for the same species were averaged in accordance with the listing policy.
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 dieldrin in fish tissue is 0.32 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 127886
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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 RWB7 TMDL data for Alamo River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Dieldrin.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: 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 2 monitoring site(s) (723ARDP10, 723ARGRB1)
Temporal Representation: The samples were collected between the dates of 2011-02-11 and 2011-04-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 5257
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 55
Number of Exceedances: 0
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Eighty seven samples were taken at 2 locations on the river. Thirty-two water sample results could not be used in the assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the sample results were zero and the detection limit could not be determined. The 55 acceptable water quality samples were generally collected from 8/1969 through 4/1992. Of these total samples, none exceed the CTR Criteria (USGS, 2007).
Data Reference: Data for organic and inorganic chemicals in water and sediment samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported on the National Water Information System (NWIS) Water Quality database. 1961-2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) Criterion Maximum Concentration (CMC) 0.24 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 at the following Alamo River locations: USGS Station No. 10254670 located at Drop 3 near Calipatria, Ca, and USGS Station No. 10254730 near Niland, Ca.
Temporal Representation: Eighty-seven samples were collected. Samples were generally collected from 8/1969 through 4/1992. Eight samples were collected in 1969, 78 samples were collected from 1970-1979, 0 samples were collected from 1980-1989, and 1 sample was collected from 1990-1992.
Environmental Conditions:
QAPP Information: Assume samplers used standard USGS methods for sample collection (Wilde, variously dated). Assume analysts used standard analytical methods and quality assurance as described in (USGS, 2007).
QAPP Information Reference(s): Data for organic and inorganic chemicals in water and sediment samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported on the National Water Information System (NWIS) Water Quality database. 1961-2005.
  Field measurements: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A6. In United States Geological Survey (USGS). Variously dated. National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at http://pubs.water.usgs.gov/twri9A.
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 129020
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the water quality standard for Dieldrin. Although a total of 12 samples were collected, 10 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: 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 7 station(s): (Station Codes 723ARDP06, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARGRB1, 723ARINTL, 723NRRCD3).
Temporal Representation: Date for this waterbody was collected over the date range 2012-10-15 to 2013-10-21
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 35262
 
Pollutant: Dieldrin
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: Twelve 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 Dieldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: 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 Alamo River was collected at 2 monitoring sites [ Alamo River Outlet, Alamo River at International Boundary]
Temporal Representation: Data was collected over the time period 10/25/2005-10/28/2008.
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 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 128724
 
Pollutant: Dieldrin
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: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB7 TMDL data for Alamo River to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality standard for Dieldrin. Although a total of 3 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 RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 2 station(s): (Station Codes 723ARDP10, 723ARGRB1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-04-22 to 2011-04-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 5201
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 55
Number of Exceedances: 55
 
Data and Information Type: Other Agencies/Organizations provided monitoring data
Data Used to Assess Water Quality: Eighty-seven water samples were taken at 2 locations on the river. Thirty-two water sample results could not be used in the assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the sample results were zero and the detection limit could not be determined. The 55 acceptable water quality samples were generally collected from 8/1969 through 4/1992. Of these total samples, 55 exceeded the CTR Criteria. The exceedences were found in samples collected from 8/13/1969 through 4/01/1992 at 2 locations (USGS, 2007).
Data Reference: Data for organic and inorganic chemicals in water and sediment samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported on the National Water Information System (NWIS) Water Quality database. 1961-2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) Criteria of 0.00014 ug/l for the protection of human health when consuming organisms from aquatic systems (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 at the following Alamo River locations: USGS Station No. 10254670 located at Drop 3 near Calipatria, Ca, and USGS Station No. 10254730 near Niland, Ca.
Temporal Representation: Eighty-seven samples were collected. Samples were generally collected from 8/1969 through 4/1992. Eight samples were collected in 1969, 78 samples were collected from 1970-1979, no samples were collected from 1980-1989, and 1 sample was collected from 1990-1992. The exceedences were found in samples collected from 8/13/1969 through 4/01/1992.
Environmental Conditions:
QAPP Information: Assume samplers used standard USGS methods for sample collection (Wilde, variously dated). Assume analysts used standard analytical methods and quality assurance as described in (USGS, 2007).
QAPP Information Reference(s): Data for organic and inorganic chemicals in water and sediment samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported on the National Water Information System (NWIS) Water Quality database. 1961-2005.
  Field measurements: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A6. In United States Geological Survey (USGS). Variously dated. National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at http://pubs.water.usgs.gov/twri9A.
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 5594
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 35
Number of Exceedances: 1
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish samples were generally collected from 6/1978 through 11/2000. Of these total samples, 1 fish fillet sample exceeded the NAS tissue guideline at 1 location. At the Calipatria location an exceedance was found in 1 channel catfish fillet composite sample collected on 4/22/1982 (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples of channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000. An exceedance was found in a sample collected on 4/22/1982.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 46598
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 30
Number of Exceedances: 30
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Two fish fillet samples and 3 whole fish samples could not be used in the assessment because the sample results were non-detect and the detection limit was above the criteria concentrations. The 28 fish fillet samples and 2 whole fish samples that were acceptable were generally collected from 6/1978 through 11/2000. Of these total samples, 28 fish fillet samples and 2 whole fish samples collected at four locations exceeded the OEHHA Fish Contaminant Goal. At the Calipatria location the exceedances were found in ;12 channel catfish fillet composite samples collected on 6/21/1978, 3/12/1979, 5/08/1980, 5/23/1981, 4/22/1982, 6/13/1983, 5/23/1984, 9/17/1985, 9/30/1987, 11/01/1996, 11/20/1997, and 11/11/1998; 2 channel catfish single fish fillet samples collected on 10/28/1989, and 10/27/1994:7 carp fillet composite samples collected on 5/23/1981, 4/22/1982, 6/13/1983, 9/17/1985, 11/18/1988, 8/03/1990, and 9/29/1993; 3 carp single fish fillet samples collected on 6/21/1978, 10/27/1994, and 11/07/2000, and; 1 spiny soft shelled turtle fillet composite sample collected on 9/20/1992. At the Brawley location 1 exceedance was found in 1 channel catfish fillet composite sample collected on 9/30/1993. At the Holtville location 1 exceedance was found in 1 carp single fish fillet sample collected on 9/30/1993. At the International Boundary location the exceedances were found in; 1 carp fillet composite sample collected on 11/20/1998, 1 redshiner whole fish composite sample collected on 11/15/1985, and; 1 mosquitofish whole fish composite sample collected on 9/02/1987 (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: The modified OEHHA Fish Contaminant Goal for dieldrin in fish tissue is 0.32 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000. The exceedances were found in samples collected from 6/21/1978 through 11/07/2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 5379
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 30
Number of Exceedances: 30
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Two fish fillet samples and 3 whole fish samples could not be used in the assessment because the sample results were non-detect and the detection limit was above the criteria concentrations. The 28 fish fillet samples and 2 whole fish samples that were acceptable were generally collected from 6/1978 through 11/2000. Of these total samples, 28 fish fillet samples and 2 whole fish samples collected at four locations exceeded the OEHHA Fish Contaminant Goal. At the Calipatria location the exceedances were found in ;12 channel catfish fillet composite samples collected on 6/21/1978, 3/12/1979, 5/08/1980, 5/23/1981, 4/22/1982, 6/13/1983, 5/23/1984, 9/17/1985, 9/30/1987, 11/01/1996, 11/20/1997, and 11/11/1998; 2 channel catfish single fish fillet samples collected on 10/28/1989, and 10/27/1994:7 carp fillet composite samples collected on 5/23/1981, 4/22/1982, 6/13/1983, 9/17/1985, 11/18/1988, 8/03/1990, and 9/29/1993; 3 carp single fish fillet samples collected on 6/21/1978, 10/27/1994, and 11/07/2000, and; 1 spiny soft shelled turtle fillet composite sample collected on 9/20/1992. At the Brawley location 1 exceedance was found in 1 channel catfish fillet composite sample collected on 9/30/1993. At the Holtville location 1 exceedance was found in 1 carp single fish fillet sample collected on 9/30/1993. At the International Boundary location the exceedances were found in; 1 carp fillet composite sample collected on 11/20/1998, 1 redshiner whole fish composite sample collected on 11/15/1985, and; 1 mosquitofish whole fish composite sample collected on 9/02/1987 (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: Office of Environmental Health Hazard Assessment (OEHHA) Fish Contaminant Goal of 0.46 ug/kg to protect human health when consuming fish (OEHHA, 2008).
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
  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: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000. The exceedances were found in samples collected from 6/21/1978 through 11/07/2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 35514
 
Pollutant: Dieldrin
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 data for Alamo River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 1 monitoring site [ Alamo River Outlet]
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 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 35305
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Dieldrin.
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: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 2 monitoring sites [ Alamo River Outlet, Alamo River at International Boundary]
Temporal Representation: Data was collected over the time period 10/25/2005-4/21/2008.
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 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 125626
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
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 Alamo River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 6 (Station Codes: 723ARDP06, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARGRB1, 723ARINTL).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-05 to 2013-04-24
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 126469
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB7 TMDL data for Alamo River to determine beneficial use support and the results are as follows 5 of the 5 samples exceeded the water quality standard for Dieldrin. Data were collected for 4 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 4 fish per composite). Of these, 3 species (Common Carp, Channel Catfish, Flathead Catfish) exceeded the water quality standard.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for dieldrin in fish tissue is 0.32 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2011-04-21 and 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 2883
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 14
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Data were collected by the RWQCB on 4/15/2003 and 6/21/01 at 7 different stations on the Alamo River. Of the 14 samples, all samples were non-detects and did not exceed either of the criteria (CRBRWQCB, 2004c).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: USEPA: freshwater acute maximum = 0.24 ppb. USEPA: freshwater chronic maximum = 0.056 ppb.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The Alamo River from Holtville Drain to the outlet into the Salton Sea only. Samples were collected at the following Alamo River sampling stations: AR-B (at the International Boundary), AR-D10 (Lower Alamo River drainshed, at Drop Structure #10), AR-D8 (Central Drain drainshed, at Drop Structure #8), AR-D6A (Holtville Main Drain drainshed, at Drop Structure #6A), AR-D6 (Rose Drain drainshed, at Drop Structure #6), AR-D3 (Central Alamo River drainshed, at Drop Structure #3), and at AR-GRB.
Temporal Representation: All samples were collected on 4/15/2003 and 6/21/01.
Environmental Conditions:
QAPP Information: Used RWQCB QA/QC in sample collection. Lab analysis was done by E.S. Babcock & Sons laboratory and a Quality Assurance Manual was provided.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 126546
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
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 Alamo River to determine beneficial use support and the results are as follows 0 of the 9 samples exceeded the water quality standard for Dieldrin. Data were collected for 5 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 2 composite(s) of Common Carp each composed of 5 fish per composite, 2 composite(s) of Tilapia spp. each composed of 5 fish per composite, 1 composite(s) of Common Carp each composed of 8 fish per composite).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Dieldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data was collected from 4 station(s) with the station code(s): 723ARDP3A, 723ARINTL, 723ARDP10, 723ARGRB1.
Temporal Representation: Data for this line of evidence were collected between 2012-03-28 and 2014-12-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 46015
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Dieldrin. Nine composites were generated from three species: channel catfish, flathead catfish and Tilapia spp. Composites comprised of 2-3 fish for channel catfish and 1 fish for flathead catfish and Tilapia spp. Composites collected at the same time on the same day for the same species were averaged in accordance with the listing policy.
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 Dieldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 126601
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB7 TMDL data for Alamo River to determine beneficial use support and the results are as follows 0 of the 5 samples exceeded the water quality standard for Dieldrin. Data were collected for 4 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 4 fish per composite).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Dieldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2011-04-21 and 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 126528
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and the results are as follows 7 of the 7 samples exceeded the water quality standard for Dieldrin. Data were collected for 5 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite, 2 composite(s) of Common Carp each composed of 5 fish per composite, 1 composite(s) of Common Carp each composed of 8 fish per composite, 2 composite(s) of Tilapia spp. each composed of 5 fish per composite). Of these species, 2 species (Common Carp, Channel Catfish) exceeded the evaluation guideline. Although a total of 9 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 indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for dieldrin in fish tissue is 0.32 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 4 station(s) with the station code(s): 723ARDP3A, 723ARINTL, 723ARDP10, 723ARGRB1.
Temporal Representation: Data for this line of evidence were collected between 2012-03-28 and 2014-12-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78414, Dieldrin
Region 7     
Alamo River
 
LOE ID: 125590
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Alamo River to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 (Station Codes: 723ARGRB1).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-06 to 2013-10-21
Environmental Conditions:
QAPP Information: Quality Assurance 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
78054
Region 7     
Alamo River
 
Pollutant: Malathion
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 placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Five lines of evidence are available in the administrative record to assess this pollutant. Six of six samples exceed the UC Davis Criteria. This pollutant is a possible cause or contributor to toxicity.

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.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six of six samples exceed the UC Davis Criteria for the protection of aquatic organisms and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be 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 78054, Malathion
Region 7     
Alamo River
 
LOE ID: 127482
 
Pollutant: Malathion
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 RWB7 TMDL data for Alamo River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
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 for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The UC Davis Criteria for Malathion for the protection of aquatic organisms is a 4 day average of 0.028 ug/L.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: Data was collected from 3 station(s) (Station Code(s) 723ARDP06, 723ARDP10, 723ARGRB1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-04-21 to 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78054, Malathion
Region 7     
Alamo River
 
LOE ID: 127955
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and the results are as follows: 3 of the 3 samples exceeded the water quality standard for Malathion. Although a total of 13 samples were collected, 10 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 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 for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The UC Davis Criteria for Malathion for the protection of aquatic organisms is a 4 day average of 0.028 ug/L.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: Data was collected from 7 station(s): (Station Codes 723ARDP06, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARGRB1, 723ARINTL, 723NRRCD3).
Temporal Representation: Date for this waterbody was collected over the date range 2011-05-10 to 2013-10-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78054, Malathion
Region 7     
Alamo River
 
LOE ID: 125390
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 3
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 3 of the 7 samples collected by SWAMP RWB7 Monitoring for Alamo River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data 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 2 stations. Monitoring site(s): ( 723ARGRB1, 723ARINTL )
Temporal Representation: The samples were collected between the dates of 2011-05-10 and 2013-10-21.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 78054, Malathion
Region 7     
Alamo River
 
LOE ID: 125398
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 2 samples collected by DPR Surface Water Study 290 Name for Alamo River 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: Chironomus dilutus, for Survival, Chironomus dilutus, for Ash Free Dry Mass
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for DPR Surface Water Study 290 Name.
 
SWAMP Data: Non-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 2 stations. Monitoring site(s): ( 723IPGT59, 723IPRF29 )
Temporal Representation: The samples were collected between the dates of 2014-10-15 and 2014-10-15.
Environmental Conditions:
QAPP Information: A QAPP was not required for this data
QAPP Information Reference(s): This is a placeholder reference for data which does not require a QAPP.
 
Line of Evidence (LOE) for Decision ID 78054, Malathion
Region 7     
Alamo River
 
LOE ID: 35589
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Twelve samples total were collected. Three samples were detected at levels above the evaluation guideline resulting in 3 exceedances. Nine 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 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: The UC Davis Criteria for Malathion for the protection of aquatic organisms is a 4 day average of 0.028 ug/L.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 2 monitoring sites [ Alamo River Outlet, Alamo River at International Boundary]
Temporal Representation: Data was collected over the time period 10/25/2005-10/28/2008.
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
69642
Region 7     
Alamo River
 
Pollutant: PCBs (Polychlorinated biphenyls)
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the section 303(d) list under sections 2.2 and 4.5 of the Listing Policy. Under these sections of the Policy, a minimum of one line of evidence is needed to assess listing status.

Fourteen lines of evidence are available in the administrative record to assess this pollutant. The LOE No. 5382 is replaced by the LOE No. 46623, which is assessed based on the current evaluation guideline. Ten fish tissue samples exceeded the 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.

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 Five of eight fish fillet fraction and five of five total fraction fish tissue samples exceeded the modified OEHHA fish contaminant goal. These exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be 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 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 126375
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and the results are as follows 2 of the 3 samples exceeded the water quality standard for PCBs (Polychlorinated biphenyls). Data were collected for 2 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite). Of these, 2 species (Common Carp, Channel Catfish) exceeded the water quality standard.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for polychlorinated biphenyls in fish tissue is 2.6 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2012-03-28 and 2014-12-02
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 46052
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 3
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 3 of 5 samples exceed the criterion for PCB, Total. Nine composites were generated from three species: channel catfish, Tilapia spp. and flathead catfish. Composites were averaged for species collected at the same time and location. Composites comprised of 2-3 fish for channel catfish and 1 fish for Tilapia spp. and flathead catfish. Total PCB was assessed for as follows: PCB aroclors and congeners were summed separately and the sum that yielded the highest value was used for the assessment.
Data Reference: 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 polychlorinated biphenyls in fish tissue is 2.6 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 126374
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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 Alamo River to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for PCBs (Polychlorinated biphenyls). Data were collected for 2 fish species (2 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum total PCB concentration of 500 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2012-03-28 and 2014-12-02
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 46059
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for PCB, Total. Nine composites were generated from three species: channel catfish, Tilapia spp. and flathead catfish. Composites comprised of 2-3 fish for channel catfish and 1 fish for Tilapia spp. and flathead catfish. Composites were averaged for species collected at the same time and location. Total PCB was assessed for as follows: PCB aroclors and congeners were summed separately and the sum that yielded the highest value was used for the assessment.
Data Reference: 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 PCB concentration of 500 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 2901
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Data were collected by the RWQCB on 6/21/2001 at 7 different stations on the Alamo River. Of the 7 samples, all samples were non-detects and did not exceed the criteria (CRBRWQCB, 2004c).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: USEPA: freshwater acute total PCB's maximum = 2 ppb. USEPA: freshwater chronic total PCB's maximum = 0.014 ppb.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The Alamo River from Central Drain to the outlet into the Salton Sea only. Samples were collected at the following Alamo River sampling stations: AR-B (at the International Boundary), AR-D10 (Lower Alamo River drainshed, at Drop Structure #10), AR-D8 (Central Drain drainshed, at Drop Structure #8), AR-D6A (Holtville Main Drain drainshed, at Drop Structure #6A), AR-D6 (Rose Drain drainshed, at Drop Structure #6), AR-D3 (Central Alamo River drainshed, at Drop Structure #3), and at AR-GRB.
Temporal Representation: All samples were collected on 6/21/2001.
Environmental Conditions:
QAPP Information: Used RWQCB QA/QC in sample collection. Lab analysis was done by North Coast Labs.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 33232
 
Pollutant: PCBs (Polychlorinated biphenyls)
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: Zero of 1 sample collected for Total PCBs exceeded the evaluation guideline.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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 (Colorado River Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for total PCB is 676 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station 723ARGRB1 (Alamo River Outlet).
Temporal Representation: The samples were collected on 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
 
Line of Evidence (LOE) for Decision ID 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 33411
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 4 samples exceeded the criterion continuous concentration for total PCB. The water body was assessed for the 3 aroclors that were contained within the data set and they include aroclor 1248, aroclor 1254, and aroclor 1260.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The total PCB criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.014 ug/L. This value corresponds to the sum of aroclors 1242, 1254, 1221, 1232, 1248, 1260, and 1016 (California Toxics Rule, 2000).
Objective/Criterion Reference: 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 723ARGRB1 (Alamo River Outlet) and 723ARINTL (Alamo River at International Boundary).
Temporal Representation: Samples collected between 4/21/2008 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 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 125588
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
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 Stream Pollution Trends data for Alamo River to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls) .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan, Colorado River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for Total PCBs from MacDonald et al., 2000a which states that the probable effect concentration for Total PCBs is 676 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 (Station Codes: 723ARGRB1).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-06 to 2013-10-21
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 125600
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
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 Alamo River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls) .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan, Colorado River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The evaluation guideline for Total PCBs from MacDonald et al., 2000a which states that the probable effect concentration for Total PCBs is 676 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 6 (Station Codes: 723ARDP3A, 723ARDP6A, 723ARINTL, 723ARDP10, 723ARDP06, 723ARGRB1).
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-05 to 2013-04-24
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 5382
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Twenty-six fish fillet samples and 4 whole fish samples could not be used in this assessment because the sample results were non-detect and it could not be determined that the detection limit was not below the criteria concentration. The 4 fish fillet samples and 1 whole fish samples that were acceptable were generally collected from 9/1985 through 11/2000. Of these total samples, 4 fish fillet samples and 1 whole fish samples collected at two locations exceeded the OEHHA Fish Contaminant Goal. At the Calipatria location the exceedances were found in ;2 carp fillet composite samples collected on 9/17/1985, and 8/03/1990, and; 2 carp single fish fillet samples on 10/27/1994, and 11/07/2000. At the International Boundary location an exceedance was found in 1 mosquitofish whole fish composite sample collected on 9/02/1987 (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: Office of Environmental Health Hazard Assessment (OEHHA) Fish Contaminant Goal of 3.6 ug/kg to protect human health when consuming fish (OEHHA, 2008).
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000. The exceedances were found in samples collected from 9/17/1985 through 11/07/2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 46623
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Twenty-six fish fillet samples and 4 whole fish samples could not be used in this assessment because the sample results were non-detect and it could not be determined that the detection limit was not below the criteria concentration. The 4 fish fillet samples and 1 whole fish samples that were acceptable were generally collected from 9/1985 through 11/2000. Of these total samples, 4 fish fillet samples and 1 whole fish samples collected at two locations exceeded the OEHHA Fish Contaminant Goal. At the Calipatria location the exceedances were found in ;2 carp fillet composite samples collected on 9/17/1985, and 8/03/1990, and; 2 carp single fish fillet samples on 10/27/1994, and 11/07/2000. At the International Boundary location an exceedance was found in 1 mosquitofish whole fish composite sample collected on 9/02/1987 (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: The modified OEHHA Fish Contaminant Goal for polychlorinated biphenyls in fish tissue is 2.6 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000. The exceedances were found in samples collected from 9/17/1985 through 11/07/2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 5640
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 35
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Thirty fish fillet samples and 5 whole fish samples were taken at 4 locations in the river. Fish samples were generally collected from 6/1978 through 11/2000. Of these total samples, none exceeded the NAS tissue guideline (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: National Academy of Science (NAS) tissue guideline of 500 ug/kg for the protection of aquatic life uses (NAS, 1973).
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Thirty fish filet samples of channel catfish, carp, largemouth bass, and spiny soft shelled turtle were collected. Thirteen channel catfish fillet composite samples were collected in the years 1978-1985, 1987,1993, and 1996-98. Two channel catfish single fish fillet samples were collected in the years 1989, and 1994. Eleven carp fillet composite samples were collected in the years 1981-85, (2)1988, 1990, (2)1993, and 2000. Two carp single fish fillet samples were collected in the years 1978, and 1994. One largemouth bass single fish fillet sample was collected in the year 1985. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Five whole fish composites of red swamp crayfish, redshiner, mosquito fish and tilapia were collected. Two red swamp crayfish whole fish composite samples were collected in the years 1979-1980. One redshiner whole fish composite sample was collected in the year 1985. One mosquitofish whole fish composite sample was collected in the year 1987. One tilapia whole fish composite sample was collected in the year 2000.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 127647
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 19
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 Alamo River to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality standard for PCBs (Polychlorinated biphenyls).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The PCB, total Congeners criteria for the protection of human health from consumption of organisms only is 0.00017 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: 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 7 monitoring site(s) (723ARDP10, 723NRRCD3, 723ARDP6A, 723ARINTL, 723ARGRB1, 723ARDP3A, 723ARDP06)
Temporal Representation: The samples were collected between the dates of 2010-10-05 and 2013-10-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 69642, PCBs (Polychlorinated biphenyls)
Region 7     
Alamo River
 
LOE ID: 33418
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of 8 samples collected for Total PCBs exceeded the evaluation guideline.
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. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (Colorado River Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for total PCB is 676 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following stations 723ARGRB1 (Alamo River Outlet) and 723ARINTL (Alamo River at International Boundary).
Temporal Representation: The samples were collected on 10/26/2005, 5/1/2006, 10/23/2007 and 4/21/2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
68609
Region 7     
Alamo River
 
Pollutant: Selenium
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status Revised
Sources: Out-of-state source
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 sections 4.1 and 4.5 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status.

Twelve lines of evidence are associated with this decision. Line of Evidence No. 2903 is a placeholder line of evidence, containing no data it is used to indicate this was a listing made prior to 2006. Line of Evidence No. 2904 has a Use Rating of Insufficient Information because of high detection limits. The data in the Line of Evidence No. 2904 cannot be used in the Final Use Rating because all of the data was below the detection limit, but the detection limit was above the criteria. No evaluation guideline for the fraction of selenium associated with sediment could be found that protects human, animal or aquatic life in fresh waters and meets the requirements of section 6.1.3 of the Listing Policy. Because of this, Line of Evidence No. 30020 received a Use Rating of Insufficient Information. Eight of samples exceed the water quality objective. LOEs 46060 and 5385 are combined to determine final use rating.

This pollutant is a possible cause or contributor to toxicity.

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.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 17 total fraction and zero of 16 fish fillet fraction fish tissue samples exceeded the OEHHA Fish Contaminant Goal.

Two of 24 water samples exceeded the Basin Plan water quality objective one hour average.

Thirty-two of 45 water samples exceeded the California Toxics Rule criteria / Basin Plan water quality objective four day average.

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 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 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 4872
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 24
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Twenty-four water quality samples were generally collected and analyzed biannually from 5/2002 through 5/2005 at 7 locations along the Alamo River. Of these total samples , 2 exceeded the Basin Plan Objective. The exceedences were found in samples collected on 5/03/2004, and 5/09/2005, from the International Boundary location (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: For all surface waters that are tributaries to the Salton Sea, a one hour average value of selenium shall not exceed .02 mg/L (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 from the following Alamo River locations: at the International Boundary, Drop 10 near Holtville, CA, Drop 8, Drop 6A, Drop 6, Drop 3, and near the outlet to the Salton Sea on Garst Road.
Temporal Representation: Twenty-four water samples were collected. Water samples were collected and analyzed biannually from 5/2002 through 5/2005 at the International Boundary and outlet to the Salton Sea locations. Samples were usually collected in May and October. The rest of the locations were sampled in May and October 2002.The exceedences were found in samples collected from 5/03/2004 through 5/09/2005.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 46836
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 12
Number of Exceedances: 8
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Twelve water quality samples were generally collected and analyzed biannually from 10/2005 through 10/2008 at 2 locations along the Alamo River . Of these total samples, eight samples exceeded the Basin Plan Objective.
Data Reference: RWB7 Trend Monitoring CY2005 CY2006 CY2007 CY2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Basin Plan: For all surface waters that are tributaries to the Salton Sea, a four day average value of selenium shall not exceed 5 ug/L (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 at stations: Alamo River Outlet to the Salton Sea (723 ARGRB1) and at the international boundary (723 ARINTL).
Temporal Representation: Data were collected 10/25/2005-10/28/2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 128987
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 30
Number of Exceedances: 21
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and results are as follows: 21 of 30 samples exceeded the water quality standard for Selenium.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: 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 9 monitoring site(s) (723ARDP03, 723ARDP06, 723ARDP08, 723ARDP10, 723ARDP3A, 723ARDP6A, 723ARGRB1, 723ARINTL, 723NRRCD3)
Temporal Representation: The samples were collected between the dates of 2010-10-05 and 2013-10-23
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 127638
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB7 TMDL data for Alamo River to determine beneficial use support and results are as follows: 3 of 3 samples exceeded the water quality standard for Selenium.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: 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 3 monitoring site(s) (723ARDP06, 723ARDP10, 723ARGRB1)
Temporal Representation: The samples were collected between the dates of 2011-11-17 and 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 46060
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Alamo River to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Selenium. Nine composites were generated from three species: channel catfish, Tilapia spp. and flathead catfish. Composites comprised of 2-3 fish for channel catfish and 1 fish for Tilapia spp. and flathead catfish. Composites collected at the same time on the same day for the same species were averaged in accordance with 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 OEHHA Fish Contaminant Goal for selenium in fish tissue is 7.4 ppm. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A background dietary consumption rate of 0.114 mg/day is applied for this micronutrient.
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 Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 125390
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 3
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 3 of the 7 samples collected by SWAMP RWB7 Monitoring for Alamo River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data 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 2 stations. Monitoring site(s): ( 723ARGRB1, 723ARINTL )
Temporal Representation: The samples were collected between the dates of 2011-05-10 and 2013-10-21.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 2903
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 2904
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Data were collected by the RWQCB on 6/21/2001 at 7 different stations on the Alamo River. All samples were non-detects with a detection limit of 100 ppb which is above the water quality objective and will not be used for the purpose of assessing compliance with the CTR (CRBRWQCB, 2004c).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: CTR: freshwater acute maximum is 20 ppb, freshwater chronic maximum is 5 ppb.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected the following Alamo River sampling stations: AR-B (at the International Boundary), AR-D10 (Lower Alamo River drainshed, at Drop Structure #10), AR-D8 (Central Drain drainshed, at Drop Structure #8), AR-D6A (Holtville Main Drain drainshed, at Drop Structure #6A), AR-D6 (Rose Drain drainshed, at Drop Structure #6), AR-D3 (Central Alamo River drainshed, at Drop Structure #3), and at AR-GRB.
Temporal Representation: All samples were collected on 6/21/2001.
Environmental Conditions:
QAPP Information: Used RWQCB QA/QC in sample collection. Lab analysis was done by North Coast Labs.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 30020
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances:
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Twenty sediment quality samples were collected and analyzed from 5/2002 through 5/2004 at seven locations in the Alamo 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. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guideline for the sediment fraction of Selenium for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.
Objective/Criterion Reference: Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, Drop 10 near Holtville, CA, Drop 8, Drop 6A, Drop 6, Drop 3, and near the outlet to the Salton Sea from Garst Road bridge.
Temporal Representation: Twenty sediment samples were collected. Sediment samples were generally collected and analyzed biannually, in May and October, from 5/2002 through 5/2005 at the International Boundary and outlet to the Salton Sea locations. The rest of the locations were sampled in May and October 2002 only.
Environmental Conditions:
QAPP Information: The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 5385
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Twenty-one fish fillet samples and 4 whole fish samples were taken at 4 locations in the river. Seven fish fillet and 1 whole fish sample results could not be used in this assessment because constituent was not analyzed in the sample. The 14 fish fillet samples and 3 whole fish samples that were acceptable were generally collected from 9/1987 through 11/2000 at four locations. Of these total samples, none exceeded the OEHHA Fish Contaminant Goal (TSMP, 2007).
Data Reference: Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. 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: Office of Environmental Health Hazard Assessment (OEHHA) Fish Contaminant Goal of 7400 ug/kg to protect human health when consuming fish (OEHHA, 2008).
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Samples were collected from the following Alamo River locations: at the International Boundary, near Holtville, CA, near Brawley, CA, and near Caliptaria, CA.
Temporal Representation: Fish tissue samples were generally collected from 6/1978 through 11/2000. Fish tissue samples were not collected from each location every sampling round. Twenty one fish fillet samples of carp, channel catfish, spiny soft shelled turtle were collected. Seven carp fillet composite samples were collected in the years 1981-82, 1987-88, 1990, (2)1993. Two carp single fish fillet samples were collected in the years 1994, and 2000. Ten channel catfish fillet composite samples were collected in the years 1978-82, 1987, 1993, 1996-98. One channel catfish single fish fillet sample was collected in the year 1994. One spiny soft shelled turtle fillet composite sample was collected in the year 1992. Four whole fish composite samples of red swamp crayfish, tilapia, mosquitofish, and red shiner were collected. One red swamp crayfish whole fish composite sample was collected in the year 1980. One tilapia whole fish composite sample was collected in the year 2000. One mosquitofish whole fish composite sample was collected in the year 1987. One red shiner whole fish composite was collected in the year 1985.
Environmental Conditions:
QAPP Information: The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).
QAPP Information Reference(s): Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.
 
Line of Evidence (LOE) for Decision ID 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 125398
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 2 samples collected by DPR Surface Water Study 290 Name for Alamo River 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: Chironomus dilutus, for Survival, Chironomus dilutus, for Ash Free Dry Mass
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for DPR Surface Water Study 290 Name.
 
SWAMP Data: Non-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 2 stations. Monitoring site(s): ( 723IPGT59, 723IPRF29 )
Temporal Representation: The samples were collected between the dates of 2014-10-15 and 2014-10-15.
Environmental Conditions:
QAPP Information: A QAPP was not required for this data
QAPP Information Reference(s): This is a placeholder reference for data which does not require a QAPP.
 
Line of Evidence (LOE) for Decision ID 68609, Selenium
Region 7     
Alamo River
 
LOE ID: 126245
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 11
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 Alamo River to determine beneficial use support and the results are as follows 0 of the 11 samples exceeded the water quality standard for Selenium. Data were collected for 6 fish species (2 composite(s) of Common Carp each composed of 5 fish per composite, 1 composite(s) of Bluegill each composed of 5 fish per composite, 15 composite(s) of Tilapia spp. each composed of 1 fish per composite, 10 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Largemouth Bass each composed of 1 fish per composite, 1 composite(s) of Flathead Catfish each composed of 1 fish per composite).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The OEHHA Fish Contaminant Goal for selenium in fish tissue is 7.4 ppm. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A background dietary consumption rate of 0.114 mg/day is applied for this micronutrient. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 4 station(s) with the station code(s): 723ARDP3A, 723ARDP10, 723ARINTL, 723ARGRB1.
Temporal Representation: Data for this line of evidence were collected between 2012-10-16 and 2014-12-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
68238
Region 7     
Alamo River
 
Pollutant: Toxaphene
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the section 303(d) list under section 4.5 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status.

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

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Twenty-four of 24 total fraction fish tissue samples exceeded the OEHHA fish contaminant goal and three of three fish fillet fraction fish tissue samples exceeded the modified OEHHA fish contaminant goal. Nine fish fillet fraction samples 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.

Twenty-four of 32 total fraction and three of ten fish fillet fraction fish tissue samples exceeded the NAS fish tissue guideline.

These exceed the allowable frequency listed in Table 4.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be 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 68238, Toxaphene
Region 7     
Alamo River
 
LOE ID: 126455
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB7 Monitoring data for Alamo River to determine beneficial use support and the results are as follows 2 of the 2 samples exceeded the water quality standard for Toxaphene. Data were collected for 2 fish species (1 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 1 fish per composite). Of these, 2 species (Common Carp, Channel Catfish) exceeded the water quality standard.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for toxaphene in fish tissue is 4.3 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2012-03-28 and 2012-03-28
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68238, Toxaphene
Region 7     
Alamo River
 
LOE ID: 46061
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 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 Alamo River to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Toxaphene. Nine composites were generated from three species: channel catfish, Tilapia spp. and flathead catfish. Composites comprised of 2-3 fish for channel catfish and 1 fish for Tilapia spp. and flathead catfish. Nine samples 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.
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 toxaphene in fish tissue is 4.3 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data for this line of evidence for Alamo River was collected at 3 monitoring sites [ Alamo River at Drop 6A Holtville Drain - 723ARDP6A, Alamo River Outlet - 723ARGRB1, Alamo River/Brawley - 723ARBRAW]
Temporal Representation: Data was collected over the time period 11/2/2004-11/9/2004.
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 68238, Toxaphene
Region 7     
Alamo River
 
LOE ID: 126477
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB7 TMDL data for Alamo River to determine beneficial use support and the results are as follows 1 of the 1 samples exceeded the water quality standard for Toxaphene. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 1 fish per composite, 1 composite(s) of Common Carp each composed of 1 fish per composite, 1 composite(s) of Channel Catfish each composed of 4 fish per composite). Of these species, 1 species (Channel Catfish) exceeded the evaluation guideline. Although a total of 3 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 RWB7 TMDL.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)
Objective/Criterion Reference: Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for toxaphene in fish tissue is 4.3 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 2 station(s) with the station code(s): 723ARGRB1, 723ARDP10.
Temporal Representation: Data for this line of evidence were collected between 2011-11-17 and 2011-11-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68238, Toxaphene
Region 7     
Alamo River
 
LOE ID: 128960
 
Pollutant: Toxaphene
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 Alamo River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 2 station(s) (Station Code(s) 723ARDP10, 723ARGRB1).
Temporal Representation: Date for this waterbody was collected over the date range 2012-05-07 to 2012-10-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68238, Toxaphene
Region 7     
Alamo River
 
LOE ID: 127201
 
Pollutant: Toxaphene
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 Alamo River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criteria for the protection of human health from consumption of organisms only is 0.00075 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 2 station(s) (Station Code(s) 723ARDP10, 723ARGRB1).
Temporal Representation: Date for this waterbody was collected over the date range 2012-05-07 to 2012-10-17
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68238, Toxaphene
Region 7     
Alamo River
 
LOE ID: 5651
 
Pollutant: Toxaphene
LOE Subgroup: