BIOACCUMULATION APPROACH Long-term annual or twice-a-year monitoring of resident fish

1. 1 0.9 0.8 0.7 0.6 ug/g 0.5 0.4 0.3 0.2 0.1 0 EFK 24.8 EFK 23.4 EFK 18.2 EFK13.8 EFK 6.3 PCK 6.9 PCK 1.6 CRK 15.0 2007 East Fork Poplar Creek Poplar Creek Clinch River CONTAMINANTS IN FISH FROM THE CLINCH RIVER WATERSHED PRIOR TO THE KINGSTON FLY ASH RELEASE: AN ASSESSMENT OF BASELINE CONDITIONSM.J. Peterson1, T.F. Baker2, T.J. Mathews1, W.K. Roy1, and G.R. Southworth11Environmental Sciences Division, Oak Ridge National Laboratory. Oak Ridge, Tennessee2Tennessee Valley Authority, Chattanooga, Tennessee IMPORTANCE OF BASELINE DATA Assessments of the impact of a point source contaminant release on lotic ecosystems often include before and after release comparisons. Ideally, long-term trends in contaminant concentrations in fish at locations around the point source would be available to provide a baseline for post-spill comparisons. Relative to the Kingston fly ash release, there is very little site-specific fish contaminant data available prior to the release. However, Oak Ridge National Laboratory (ORNL) and the Tennessee Valley Authority (TVA) have conducted long-term and extensive sampling of fish throughout the Clinch River system (Figure 1). Historical fish contaminant datasets were reviewed in an effort to define the likely pre-spill contaminant concentrations for some species that could be useful in assessing human and ecological risks associated with the Kingston event. In addition, determination of “background” contaminant concentrations in fish from the region can help define appropriate site-specific goals for fish contaminant reduction. CONTAMINANT RESULTS IN FISH Clinch River and Lower Watts Bar Reservoir Other metals Although recent data for metals (other than mercury) in Clinch/Emory River fish prior to the fly ash spill is limited, there are good regional historical datasets useful in defining background metal concentrations for some species, and for different tissue types (e.g., fish fillet and whole-body samples). Based on these historical data, the State of Tennessee has issued fish consumption advisories in the Clinch River and Watts Bar Reservoir that focus on concerns relative to PCBs and mercury. Polychlorinated biphenyls (PCBs) ( PCB concentrations in channel catfish from sites in the Clinch River have shown a steady decline over the last 20+ years, decreasing from levels in the 1.5 to 2 µg/g range in the 1980s and 1990s to levels less than 0.5 µg/g in recent years. data collected by ORNL data collected by ORNL data collected by TVA Long term trends for metal concentrations in whole body stoneroller minnows from Hinds Creek reference site Mercury Upper Clinch and Emory Rivers sources of mercury to downstream waters Mercury concentrations in fish from some sites are above the 0.3 µg/g EPA guidance value, with a clear spatial pattern of decreasing concentrations with distance from point sources upstream of Kingston. SUMMARY Map showing select ORNL fish sampling sites. Very little available information on fish contaminant concentrations, particularly for metals other than mercury, very near the spill site. Based on results from sites near the KIF in the Clinch River, fish have elevated PCB and slightly elevated mercury levels PCB levels in fish from the Watts Bar Reservoir near the KIF have been decreasing over time Mercury sources near Oak Ridge and upstream Emory but fish tissue concentrations decrease with distance downstream Fish tissue obtained prior to the spill from near the Kingston Fossil Plant (KIF) discharge has been archived and may be analyzed in the future, providing additional information regarding the potential baseline conditions near the spill site. To evaluate the role of the KIF fly ash release on fish concentrations, long-term monitoring of multiple reference sites is important BIOACCUMULATION APPROACH Long-term annual or twice-a-year monitoring of resident fish Watershed scale ORNL approach Human health assessment: Muscle tissue from game fish 6-8 individual fish analyzed per site standardized sizes, age, sex for comparability Ecological risk assessment: Typically 3 x 10-fish composites (forage fish) TVA approach composite sample of equal aliquots of 5 fish fillets Watts Bar sites Mercury concentrations in fish collected from Watts Bar sites around the spill site are similar to concentrations seen at many Tennessee Valley reservoir and tributary sites Acknowledgements: This work was sponsored by the U.S. Department of Energy, under contract number DE-AC05-00OR22725 with UT-Battelle LLC.