Data Used to Assess Water Quality: |
Fish were sampled for tissue analysis at two locations from the Thermalito Afterbay. A total of 3 out of 33 samples exceeded the USEPA fish tissue criterion for human health. 1) North Thermalito Afterbay: The average wet weight mercury concentration in fish tissue was 0.17 ppm for the 17 samples collected at this location. The number of fish collected per sample, the measured mercury concentrations in fish tissue, and the number of exceedances are, by species: Bluegill- one 2-fish composite sample, 0.05 ppm, no exceedances; Carp- 5 samples, 0.1-0.21 ppm (average 0.16 ppm), no exceedances; Largemouth Bass- 9 samples, 0.13-0.4 ppm (average 0.21 ppm), 1 exceedance; Redear Sunfish- 2 samples, 0.03 and 0.05 ppm, no exceedances. 2) South Thermalito Afterbay: The average wet weight mercury concentration in fish tissue was 0.21 ppm for the 16 samples collected at this location. The number of fish collected per sample, the measured mercury concentrations in fish tissue, and the number of exceedances are, by species: Carp- one 5-fish composite sample, 0.13 ppm, no exceedances; Largemouth Bass- 15 samples, 0.1-0.53 ppm (average 0.21 ppm), 2 exceedances. All 33 composite and individual 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. |
|
DECISION ID |
11663 |
|
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. Eight 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. Five of 7 composite fish and crayfish tissue samples collected at three locations in Thermalito Afterbay in 2002 exceed the OEHHA fish contaminant goal for human health and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. In addition, 3 out of 4 fish tissue samples collected at two locations in Thermalito Afterbay in 2003 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: |
|
|
|
|
LOE ID: |
21834 |
|
Pollutant: |
PCBs (Polychlorinated biphenyls) |
LOE Subgroup: |
Pollutant-Tissue |
Matrix: |
Tissue |
Fraction: |
Fish whole body |
|
Beneficial Use: |
Commercial or recreational collection of fish, shellfish, or organisms |
|
Number of Samples: |
7 |
Number of Exceedances: |
5 |
|
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 at three locations in Thermalito Afterbay:Northern Region: 1 of 1 composite crayfish sample exceeded 3.6 ng/g; concentrations was 7.3 ng/g.Southern Region (Ski Cove): 1 of 1 composite crayfish sample and 2 of 2 fish samples exceeded 3.6 ng/g; concentrations were 5.6 and 112.4 ng/g in largemouth bass and common carp composites, respectively. Potter's Pond: 1 of 1 composite common carp sample and 0 of 2 largemouth bass composite samples exceeded 3.6 ng/g. Concentrations were 22.5 ng/g in the common carp and 1.9 and 3.4 ng/g in the largemouth bass samples. Fish collected had fork lengths greater than 240 mm. 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 and southern regions of Thermalito Afterbay. Fish were not found in the northern region, but crayfish were sampled there. |
Temporal Representation: |
Samples were collected on: 05/28/02, 09/12/02, 09/13/02, 09/18-20/02 and 12/03/02. 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). |
Environmental Conditions: |
|
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): |
|
|
LOE ID: |
21835 |
|
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: |
4 |
Number of Exceedances: |
3 |
|
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 at two locations in Thermalito Afterbay:Northern Region: 0 of 1 composite largemouth bass sample exceeded 3.6 ng/g; concentrations was 3.2 ng/g total PCBs.Southern Region (Ski Cove): 3 of 3 composite fish samples exceeded 3.6 ng/g. The concentration of the largemouth bass composite was 6.9 ng/g total PCBs. Concentrations in the common carp composites were 39.7 and 93.6 ng/g total PCBs. 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. 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: |
General Protocol for Sport Fish Sampling and Analysis. Pesticide and Environmental Toxicology Branch. Office of Environmental Health Hazard Assessment. California Environmental Protection Agency. December 2005 |
|
Spatial Representation: |
Samples were collected in northern and southern regions of Thermalito Afterbay. |
Temporal Representation: |
Fish samples were collected on 04/17/03 and 06/11/03.PCBs were used in the Feather River watershed in electric power generation and other activities. See also first line of evidence. . |
Environmental Conditions: |
|
QAPP Information: |
Data quality: Acceptable.. |
QAPP Information Reference(s): |