Final California 2010 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: Thermalito Diversion Pool
Water Body ID: CAL5187001020041214114430
Water Body Type: Lake & Reservoir
 
DECISION ID
11665
Region 5     
Thermalito Diversion Pool
 
Pollutant: PCBs (Polychlorinated biphenyls)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. One 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. One of 2 samples exceeded the OEHHA fish contaminant goal for human health 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 11665, PCBs (Polychlorinated biphenyls)
Region 5     
Thermalito Diversion Pool
 
LOE ID: 21831
 
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: 2
Number of Exceedances: 1
 
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.Total PCBs in the composite of Sacramento sucker was 66.4 ng/L. Total PCBs in the crayfish composite was 3.9 ng/g. The sucker composite included 5 fish, with fork lengths 505-540 mm. Whole bodies of 10 crayfish were composited. Large crayfish were targeted for sampling.
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
 
SWAMP Data: Non-SWAMP
 
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: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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). There is only one fish sample in this dataset. People may eat crayfish from the Diversion Pool, but most consumption is expected to be of fish. Sacramento sucker are not commonly consumed. For purposes of assessing risk to human health, sucker may not be representative of PCB concentrations in other fish species that are commonly eaten.
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 at three separate locations on the Feather River downstream of Lake Oroville.
Temporal Representation: Samples were collected on 10/04/02 and 1/15/03.PCBs have been used in the Feather River watershed in electric power generation and in other activities (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):