# Draft 2008 California 303(d)/305(b) Integrated Report

# Supporting Information

## Regional Board 5 - Central Valley Region

Water Body Name: | Thermalito Forebay
Water Body ID: | CAL5154000020000209143205
Water Body Type: | Lake & Reservoir

DECISION ID | 11650
Pollutant: | Cadmium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 26 dissolved cadmium samples exceeded the USEPA (CTR) dissolved cadimum-based numeric criteria for freshwater aquatic life protection and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 11650

LOE ID: | 21826
Pollutant: | Cadmium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 26
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | 26 samples were taken from Thermalito North Forebay between 2002 and 2004. 0 of the 26 samples exceeds guidelines for dissolved cadmium.
Data Reference: | Project effects on water quality designated beneficial uses for surface waters, and results for bacterial monitoring of swimming areas in 2003. FERC Project No. 2100. Sacramento, CA: State of CA Department of Water Resources
Water Quality Objective/Criterion: | California Toxics Rule Criteria (USEPA) - Freshwater Aquatic Life ProtectionContinuous Concentration (4-day Average) calculated based on the following formula (EXP(0.7852*LN(hardness)-2.715))*(1.101672-(LN(hardness)*0.041838))U.S. Environmental Protection Agency, Federal Register, Volume 65, No. 97 (Thursday, 18 May 2000), pp. 31682-31719 [California Toxics Rule]; and Federal Register, Volume 66, No. 30 (Tuesday, 13 February 2001), pp. 9960-9962 [California Toxics Rule Correction] http://www.gpoaccess.gov/fr/browse.html.
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
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from Thermalito North Forebay.
Temporal Representation: | Samples were collected from April 2002 through April 2004. Samples were collected at monthly intervals.
Environmental Conditions: |
QAPP Information: | Data quality: Excellent. Quality Control for all of the elements described in section 6.1.4 of the Policy was conducted in accordance with the Laboratory QAPP developed by the State of California Resources Agency Department of Water Resources (DWR, 2005). Quality Assurance Project Plan for Oroville Facilities Relicensing FERC Project No. 2100 SP-W1. Department of Water Resources (DWR). Oroville Facilities Relicensing FERC Project No. 2100. January 2005.
QAPP Information Reference(s):

DECISION ID | 11651
Pollutant: | Copper
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 47 samples exceeded the the 4-day maximum criterion for dissolved copper and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 11651

LOE ID: | 21896
Pollutant: | Copper
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 47
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | 47 samples were taken from Thermalito North Forebay between April 2002 and April 2004. Zero of the 47 samples exceed guidelines for dissolved copper.
Data Reference: | Project effects on water quality designated beneficial uses for surface waters, and results for bacterial monitoring of swimming areas in 2003. FERC Project No. 2100. Sacramento, CA: State of CA Department of Water Resources
Water Quality Objective/Criterion: | California Toxics Rule Criteria (USEPA) - Freshwater Aquatic Life ProtectionContinuous Concentration (4-day Average) calculated based on the fallowing formula (e{.8545xLN[hardness]}-1.702) x(0.960) which incorporates hardnessU.S. Environmental Protection Agency, Federal Register, Volume 65, No. 97 (Thursday, 18 May 2000), pp. 31682-31719 [California Toxics Rule]; and Federal Register, Volume 66, No. 30 (Tuesday, 13 February 2001), pp. 9960-9962 [California Toxics Rule Correction] http://www.gpoaccess.gov/fr/browse.html.
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
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from Thermalito North Forebay
Temporal Representation: | Samples were collected between April 2002 and April 2004.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Quality Control for all of the elements described in section 6.1.4 of the Policy was conducted in accordance with the Laboratory QAPP developed by the State of California Resources Agency Department of Water Resources (DWR, 2005). Quality Assurance Project Plan for Oroville Facilities Relicensing FERC Project No. 2100 SP-W1. Department of Water Resources (DWR). Oroville Facilities Relicensing FERC Project No. 2100. January 2005.
QAPP Information Reference(s):

DECISION ID | 11653
Pollutant: | DDT
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 2 samples exceeded the OEHHA 2008 Screening value of 21 μg/kg total DDT wet weight for fish tissue and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 11653

LOE ID: | 23368
Pollutant: | DDT
LOE Subgroup: | Pollutant-Tissue
Matrix: | Tissue
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Two samples were collected from Lake Oroville, South Thermalito Forebay (swim area) in 2003. One Pike Minnow and one Common Carp fish were analyzed for total DDT (DDD,o,p', DDD,p,p', DDE,p,p', DDMU,p,p'). The OEHHA 2008 fish contaminant goal was used to evaluate presence of an exceedance. One sample of Common Carp and one sample of Pike Minnow did not exceed the OEHHA 2008 screening value.
Data Reference: | Oroville Facilities Relicensing-FERC Project No. 2100. Contaminant accumulation in fish, sediments, and the aquatic food chain. Sacramento, CA: State of CA Department of Water Resources
Water Quality Objective/Criterion: | Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer (CVRWQCB, 2007).
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | OEHHA 2008 Screening value of 21 ug/kg total DDT wet weight for fish tissue
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: | Two samples were collected from Lake Oroville, South Thermalito Forebay (swim area).
Temporal Representation: | Samples were collected in 2003.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number-2003-0826) requirements (CVRWQCB, 2003).
QAPP Information Reference(s):

DECISION ID | 11654
Pollutant: | Lead
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 26 samples exceeded the Basin Plan criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 11654

LOE ID: | 21898
Pollutant: | Lead
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 26
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | 26 samples were taken from Thermalito North forebay between 2002 and 2004. None of 26 samples exceed guidelines for dissolved lead.
Data Reference: | Project effects on water quality designated beneficial uses for surface waters, and results for bacterial monitoring of swimming areas in 2003. FERC Project No. 2100. Sacramento, CA: State of CA Department of Water Resources
Water Quality Objective/Criterion: | California Toxics Rule Criteria (USEPA) - Freshwater Aquatic Life ProtectionContinuous Concentration (4-day Average) calculated based on the following formula: (e(1.273xLN(hardness))-4.705)x((1.46203-LN(hardness))x0.145712)U.S. Environmental Protection Agency, Federal Register, Volume 65, No. 97 (Thursday, 18 May 2000), pp. 31682-31719 [California Toxics Rule]; and Federal Register, Volume 66, No. 30 (Tuesday, 13 February 2001), pp. 9960-9962 [California Toxics Rule Correction] http://www.gpoaccess.gov/fr/browse.html.
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
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from Thermalito North Forebay.
Temporal Representation: | Samples were collected from April 2002 through April 2004. Samples were collected at monthly intervals.
Environmental Conditions: |
QAPP Information: | Data quality: Excellent. Quality Control for all of the elements described in section 6.1.4 of the Policy was conducted in accordance with the Laboratory QAPP developed by the State of California Resources Agency Department of Water Resources (DWR, 2005). Quality Assurance Project Plan for Oroville Facilities Relicensing FERC Project No. 2100 SP-W1. Department of Water Resources (DWR). Oroville Facilities Relicensing FERC Project No. 2100. January 2005.
QAPP Information Reference(s):

DECISION ID | 11657
Pollutant: | PCBs (Polychlorinated biphenyls)
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Sources: | Source Unknown
Expected TMDL Completion Date: | 2021
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Two of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Two of 2 samples exceeded the OEHHA fish contaminant goal for human health 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.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 11657

LOE ID: | 21832
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: | 2
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Samples were analyzed for the presence of 48 individual PCB congeners and Aroclors 1254 and 1260. Data evaluated were the sum of PCB congeners (total PCBs), reported as ng/g, wet weight. OEHHA and SWAMP recommend use of total PCBs for evaluating contamination.Samples were collected in the North Forebay Recreation Area. The concentration of total PCBs in 2 of 2 composite fish sample exceeded 3.6 ng/g. Concentrations were 186.8 and 281.4 ng/g total PCBs in pikeminnow and common carp composite samples, respectively. Fish collected had fork lengths between 625 and 760 mm. Composite samples were comprised of fillet samples from up to 10 individual fish of the same species. Composites were composed of fish with no greater than 25% difference in fork length between the largest and smallest fish.
Data Reference: | Oroville Facilities Relicensing-FERC Project No. 2100. Contaminant accumulation in fish, sediments, and the aquatic food chain. Sacramento, CA: State of CA Department of Water Resources
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. The objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | The California Office of Environmental Health Hazard Assessment (OEHHA) Fish Contaminant Goal for total PCBs in fish is 3.6 ng/g (3.6 ppb), wet weight, to protect human health. This concentration in fish tissue should not be exceeded, based on a total fish and shellfish consumption rate of 8 ounces (prior to cooking) per week (32 g fish/day) (OEHHA, 2008). This fish contaminant goal incorporates a maximum cancer risk level of one in a million (no more than one additional cancer in a population of one million people consuming these fish).
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 in the northern part of Thermalito Forebay. Fish were not available in the main area of the Forebay
Temporal Representation: | Samples were collected on 09/17/02.
Environmental Conditions: | PCBs have been used in the Feather River watershed in electric power generation and in other activities. Some remediation was performed for two contamination events that occurred in the 1980s: PCB-containing oil applied to a dirt road entered the Ponderosa Reservoir in surface runoff (South Fork Feather River) and PCBs contaminated the soil and water at Belden Forebay (North Fork Feather River) after a landslide damaged powerhouses (CVRWQCB, 1987).
QAPP Information: | Data quality: Acceptable.. Quality Control for all of the elements described in section 6.1.4 of the Policy was conducted in accordance with the Laboratory QAPP developed by the State of California Resources Agency Department of Water Resources (DWR, 2005). Quality Assurance Project Plan for Oroville Facilities Relicensing FERC Project No. 2100 SP-W1. Department of Water Resources (DWR). Oroville Facilities Relicensing FERC Project No. 2100. January 2005.
QAPP Information Reference(s):