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

# Supporting Information

## Regional Board 5 - Central Valley Region

Water Body Name: | Oroville, Lake
Water Body ID: | CAL5181200020020430135809
Water Body Type: | Lake & Reservoir

DECISION ID | 14192
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 97 samples exceeded 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 14192

LOE ID: | 22353
Pollutant: | Copper
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 197
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | 197 samples were taken from Lake Oroville between April 2002 and April 2004. Zero of the 197 samples exceeded 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 Lake Oroville (south fork, north fork, middle fork, main body, dam).
Temporal Representation: | Samples were collected between March 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 | 14194
Pollutant: | Fecal Coliform
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 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 101 samples exceeded the fecal coliform objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 14194

LOE ID: | 22354
Pollutant: | Fecal Coliform
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Water Contact Recreation
Number of Samples: | 101
Number of Exceedances: | 0
Data and Information Type: | PATHOGEN MONITORING
Data Used to Assess Water Quality: | The Department of Water Resources collected 103 samples from April 2002 to April 2004. The geometric mean per month per site was calculated from the samples and 0 out of the 101 calculated geometric means exceeded the evaluation objective.
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: | In waters designated for contact recreation (REC-1), the fecal coliform concentration based on a minimum of not less than five samples for any 30-day period shall not exceed a geometric mean of 200/100 ml, nor shall more than ten percent of the total number of samples taken during any 30-day period exceed 400/100 ml.
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: |
Guideline Reference:
Spatial Representation: | Samples were collected from Lake Oroville at 5 locations: 1)North Fork, 2) Middle Fork, 3) South Fork, 4) Main Body. and 5) At Dam.
Temporal Representation: | Sampling occurred from April 2002 to 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 | 14193
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 lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 123 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 14193

LOE ID: | 22318
Pollutant: | Lead
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 123
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | 123 samples were taken from Lake Oroville between 2002 and 2004. 0 of the 123 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 the Main Body, the Middle Fork, North Fork, South Fork and at the Dam of Lake Oroville.
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 | 14191
Pollutant: | Oxygen, Dissolved
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 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 28 samples fell below the criteria specified in the Basin Plan and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 14191

LOE ID: | 22335
Pollutant: | Oxygen, Dissolved
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Cold Freshwater Habitat
Aquatic Life Use: | Cold Freshwater Habitat
Number of Samples: | 28
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | 28 samples were taken from the surface (at depth of 0.15 meter) of Lake Oroville between April 2002 and April 2004. 0 sample exceeds the minimum dissolved oxygen concentration (7 mg/L) and 0 sample exceeds 5 mg/L. 1462 samples were taken from variable depths of Lake Oroville between April 2002 and April 2004. 64 samples exceed 7 mg/L and 5 samples exceed 5 mg/L. The 64 samples (DO<7 mg/L) were measured at water depth below 3 meters and the 5 samples (DO<5 mg/L) were measured at water depth below 17 meters.
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: | Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007a)(COLD), Minimum Dissolved Oxygen concentration of 7mg/L(SPWN), Minimum Dissolved Oxygen concentration of 7mg/L(WARM), Minimum Dissolved Oxygen concentration of 5mg/L
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: |
Guideline Reference:
Spatial Representation: | Samples were collected from Lake Oroville main body.
Temporal Representation: | Samples were collected between April 2002 and April 2004 monthly. Some samples were taken at one-meter depth interval between 1 and 150 meters. Surface water was taken at 0.15 meter.
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 | 12797
Pollutant: | Mercury
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Sources: | Resource Extraction
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. Three lines of evidence are available in the administrative record to assess this pollutant. Seventy-three 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. Seventy-three of 108 samples exceed the USEPA fish tissue criterion for human health and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. In addition, zero out of 80 water samples exceed the USEPA (CTR) mercury-based numeric criterion for human health. This number of exceedances 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 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 12797

LOE ID: | 22044
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Tissue
Matrix: | Tissue
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 7
Number of Exceedances: | 3
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fish were sampled for tissue analysis at four locations from Lake Oroville. 1) South Fork Arm near McCabe Cove: 1 of 2 composite samples exceeded 0.3 ppm; 0.23 and 0.34 ppm. 2) Upper Middle Fork Arm: 1 of 1 composite samples exceeded 0.3 ppm; 0.70 ppm. 3) North Fork Arm near Bloomer Canyon: 0 of 2 composite samples exceeded 0.3 ppm; 0.12 and 0.23 ppm. 4) Lime Saddle Marina: 1 of 2 composite samples exceeded 0.3 ppm; 0.20 and 0.55 ppm. Fish tissue was analyzed from Largemouth Bass and Spotted Bass. All 7 composite samples were collected from fish with average total lengths greater than 150 mm, which represent fish most commonly caught and consumed by sport fishers and their families.
Data Reference: | Mercury Contamination in Fish from Northern California Lakes and Reservoirs. State of California. The Resources Agency. Department of Water Resources. Northern District. July 2007
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 USEPA Fish Tissue Residue Criterion for methylmercury in fish is 0.3 mg/kg (0.3 ppm) for the protection of human health. This is the concentration in fish tissue that should not be exceeded based on a total fish and shellfish consumption-weighted rate of 0.0175 kg fish/day. (USEPA, 2001)
Guideline Reference: | Water Quality Criterion for the Protection of Human Health: Methylmercury. Final. United States Environmental Protection Agency Office of Science and Technology Office of Water. EPA-823-R-01-001. January 2001
Spatial Representation: | Samples were collected at four locations throughout Lake Oroville: two locations from the North Fork Arm (Lime Saddle Marina and North Fork Arm near Bloomer Canyon); and one location each from the upper Middle Fork Arm and South Fork Arm near McCabe Cove.
Temporal Representation: | Fish samples were collected during the spring and summer of 2000 and 2001.
Environmental Conditions: | Significant gold mining activity occurred during the Gold Rush era within the Lake Oroville watershed and the lands inundated by Lake Oroville. In addition, small-scale commercial and recreational gold mining activities presently continue in the upper Feather River watershed upstream of Lake Oroville (DWR, 2006).
QAPP Information: | Data quality: Excellent.. Quality control for sample collection, preparation, handling, and analyses were conducted in accordance with the Surface Water Ambient Monitoring Program Quality Assurance Program Plan (Puckett, 2002) with the following exception: instead of wrapping fish in Teflon sheets before being frozen and transported to the laboratory, the fish were wrapped in aluminum foil (dull side to skin). This wrapping method should not have affected mercury concentrations. Quality control procedures for selection of target fish species and compositing of samples followed the General Protocol for Sport Fish Sampling and Analysis developed by OEHHA (Gassel and Brodberg, 2005).
QAPP Information Reference(s):
LOE ID: | 22043
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Tissue
Matrix: | Tissue
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 101
Number of Exceedances: | 70
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fish were sampled for tissue analysis at six locations from Lake Oroville. 1) Spillway Arm near the Intake Structure: 11 of 12 samples exceeded 0.3 ppm; 0.35 ppm average wet weight concentration. 2) Bidwell Marina Arm: 13 of 14 samples exceeded 0.3 ppm; 0.51 ppm average wet weight concentration. 3) South Fork Arm near McCabe Cove: 13 of 19 samples exceeded 0.3 ppm; 0.45 ppm average wet weight concentration. 4) Upper Middle Fork Arm: 18 of 21 samples exceeded 0.3 ppm; 0.46 ppm average wet weight concentration. 5) North Fork Arm near Bloomer Canyon: 7 of 15 samples exceeded 0.3 ppm; 0.31 ppm average wet weight concentration. 6) Lime Saddle Marina: 8 of 20 samples exceeded 0.3 ppm; 0.31 ppm average wet weight concentration. Fish tissue was analyzed from Black Crappie, Bluegill, Carp, Channel Catfish, Coho Salmon, Green Sunfish, Largemouth Bass and Spotted Bass. All 101 samples were collected from fish with total lengths greater than 150 mm, which represent fish most commonly caught and consumed by sport fishers and their families.
Data Reference: | Reports, data files, and QAPP documentation for characterization of surface waters of Lake Oroville and the Feather River (Butte County), associated with the Oroville Facilities Hydroelectric Project (FERC #2100).
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 USEPA Fish Tissue Residue Criterion for methylmercury in fish is 0.3 mg/kg (0.3 ppm, wet weight) for the protection of human health. This is the concentration in fish tissue that should not be exceeded based on a total fish and shellfish consumption-weighted rate of 0.0175 kg fish/day (USEPA, 2001).
Guideline Reference: | Water Quality Criterion for the Protection of Human Health: Methylmercury. Final. United States Environmental Protection Agency Office of Science and Technology Office of Water. EPA-823-R-01-001. January 2001
Spatial Representation: | Samples were collected at six locations throughout Lake Oroville: two locations from the North Fork Arm (Lime Saddle Marina and North Fork Arm near Bloomer Canyon); and one location each from the upper Middle Fork Arm, South Fork Arm near McCabe Cove, Bidwell Canyon Arm and Spillway Arm near the Intake Structure.
Temporal Representation: | Fish samples were collected during seven sampling events from 3/10/2003 to 10/30/2003.
Environmental Conditions: | Significant gold mining activity occurred during the Gold Rush era within the Lake Oroville watershed and the lands inundated by Lake Oroville. In addition, small-scale commercial and recreational gold mining activities presently continue in the upper Feather River watershed upstream of Lake Oroville (DWR, 2006).
QAPP Information: | Data quality: Excellent.. Quality control for sample collection, preparation, handling, and analyses were conducted in accordance with the Surface Water Ambient Monitoring Program Quality Assurance Program Plan (Puckett, 2002) with the following exception: instead of wrapping fish in Teflon sheets before being frozen and transported to the laboratory, the fish were wrapped in aluminum foil (dull side to skin). This wrapping method should not have affected mercury concentrations. Quality control procedures for selection of target fish species and compositing of samples followed the General Protocol for Sport Fish Sampling and Analysis developed by OEHHA (Gassel and Brodberg, 2005).
QAPP Information Reference(s):
LOE ID: | 22100
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 80
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | A total of 246 water samples were collected at five locations from Lake Oroville representing eighty 30-day average samples. None of the eighty 30-day average samples exceeded the USEPA (CTR) mercury-based numeric criterion for human health. The total recoverable mercury concentrations in water ranged from 0.2 ng/l to 11.9 ng/l with an average of 8.4 ng/l for the eighty 30-day average samples.
Data Reference: | Reports, data files, and QAPP documentation for characterization of surface waters of Lake Oroville and the Feather River (Butte County), associated with the Oroville Facilities Hydroelectric Project (FERC #2100).
Water Quality Objective/Criterion: | The USEPA (CTR) numeric criterion for the protection of human health for the consumption of both water and fish that live in the water is 50 ng/l (30-day average) for total recoverable mercury (40 CFR 131.38).
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 at five locations throughout Lake Oroville: from the North Fork Arm, the Middle Fork Arm, the South Fork Arm, the main body of the lake and near the Oroville Dam Spillway.
Temporal Representation: | Water samples were collected during 70 sampling events from 4/23/2002 to 4/26/2004.
Environmental Conditions: | Significant gold mining activity occurred during the Gold Rush era within the Lake Oroville watershed and the lands inundated by Lake Oroville. In addition, small-scale commercial and recreational gold mining activities presently continue in the upper Feather River watershed upstream of Lake Oroville (DWR, 2006).
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 QAPP developed by the State of California Resources Agency, Department of Water Resources (DWR, 2005).
QAPP Information Reference(s): | Reports, data files, and QAPP documentation for characterization of surface waters of Lake Oroville and the Feather River (Butte County), associated with the Oroville Facilities Hydroelectric Project (FERC #2100).

DECISION ID | 12793
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. Two lines of evidence are available in the administrative record to assess this pollutant. Thirty-three 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. Thirty-three of 38 samples exceed 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 12793

LOE ID: | 22372
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: | 19
Number of Exceedances: | 14
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.Fish were collected at six locations in Lake Oroville:Spillway Arm near the Intake Structure: 3 of 3 composite samples (Coho salmon) exceeded 3.6 ng/g. The average concentration was 7.5 ng/g, wet weight.Bidwell Marina Arm: the single, individual sample (largemouth bass) did not exceed 3.6 ng/g. The concentration was 2.5 ng/g, wet weight.South Fork Arm near McCabe Cove: 2 of 2 composite samples (channel catfish and common carp) exceeded 3.6 ng/g. Middle Fork Arm, Upper Site: 4 of 4 composite samples (channel catfish and spotted bass) exceeded 3.6 ng/g. North Fork Arm near Bloomer Canyon: 4 of 5 composite and individual samples (channel catfish, white catfish, and spotted bass) exceeded 3.6 ng/g. West Branch Arm at Lime Saddle Marina: 1 of 4 composite samples (largemouth bass, spotted bass, and common carp) exceeded 3.6 ng/g. The average of total PCBs in the Lake Oroville samples was 18.0 ng/g. The range was 0.56 to 94.0 ng/g. The highest concentrations were found in samples of channel catfish and common carp.The fish sampled had total lengths greater than 150 mm. Composite samples were comprised of fillet samples from up to 12 individual fish of the same species. Most 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
| California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
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 throughout Lake Oroville from the major arms and near the dam.
Temporal Representation: | Fish samples were collected during seven sampling events from 03/10/2003 to 10/30/2003.
Environmental Conditions: | PCBs have been used in the Feather River Watershed in electric power generation and other activites. See also first line of evidence.
QAPP Information: | Data quality: Acceptable..
QAPP Information Reference(s):
LOE ID: | 22371
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: | 19
Number of Exceedances: | 19
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.Fish were collected at eight locations in Lake Oroville:Spillway Arm near the Intake Structure: 2 of 2 composite samples (spotted bass and channel catfish) exceeded 3.6 ng/g. Bidwell Marina Arm: 2 of 2 composite samples (spotted bass and channel catfish) exceeded 3.6 ng/g. South Fork Arm near McCabe Cove: 2 of 2 composite samples (spotted bass and channel catfish) exceeded 3.6 ng/g. South Fork Arm, Lower Site: 2 of 2 composite samples (spotted bass and channel catfish) exceeded 3.6 ng/g. Middle Fork Arm, Upper Site: 2 of 2 composite samples (spotted bass and channel catfish) exceeded 3.6 ng/g. Middle Fork Arm, Lower Site: 2 of 2 composite samples (spotted bass and channel catfish) exceeded 3.6 ng/g. North Fork Arm near Bloomer Canyon: 3 of 3 composite (channel catfish, common carp, and spotted bass) exceeded 3.6 ng/g. North Fork Arm near Foreman Creek: 4 of 4 composite (channel catfish, white catfish, common carp, and spotted bass) exceeded 3.6 ng/g. The average of total PCBs in the Lake Oroville samples was 30.5 ng/g. The range was 4.7 to 88.8. Composites of channel catfish had the highest concentrations. The lowest concentrations were found in spotted bass composite samples.The fish sampled had total lengths greater than 150 mm. Composite samples were comprised of fillet samples from up to 12 individual fish of the same species. Most 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 throughout Lake Oroville from the major arms and near the dam.
Temporal Representation: | Fish samples were collected between 04/05/2002 and 08/13/2002.
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):

DECISION ID | 5225
Pollutant: | Aluminum
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2006)
Revision Status | Original
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. A small portion 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. Thirty-nine of 651samples exceeded the chemical constituent water quality objective 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: | No new data were assessed for 2008. The Regional Board will update this decision when new data and information become available and are assessed.
SWRCB Board Decision / Staff Recommendation: | This is a decision made by the State Water Resources Control Board and approved by the USEPA in 2006 . No new data were assessed by the Regional Board for 2008. The decision has not changed.
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 5225

LOE ID: | 722
Pollutant: | Aluminum
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 651
Number of Exceedances: | 39
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Thirty-nine out of 651 samples exceeded the MCL criteria.
Data Reference: | Placeholder reference 2006 303(d)
Water Quality Objective/Criterion: | 0.2 ppm secondary MCL (CCR, Title 22).
Objective/Criterion Reference: | Placeholder reference 2006 303(d)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: |
Temporal Representation: |
Environmental Conditions: |
QAPP Information: | QA Info Missing
QAPP Information Reference(s):