PM08 Sediment Quality Assessment
Exhibit Hall
8:00 AM - Monday
(PM125) Spatial and temporal trends of PCBs in fish in response to natural recovery in sediments.
Booth, P1, Edwards, M1, Nielsen, D1, 1 Exponent, Inc., Bellevue, WA, USA
ABSTRACT- Twelvemile Creek and portions of Lake Hartwell, South Carolina comprise Operational Unit No. 2 (OU2) of the Sangamo-Weston Superfund Site. Sediment in OU2 of Lake Hartwell contains elevated concentrations of polychlorinated biphenyls (PCBs) and there is a fish consumption advisory for the area due to elevated PCBs in fish. A Record of Decision (ROD) was completed in 1994 stipulating monitored natural recovery as the preferred remedy. The remedy was selected on the basis of sampling and modeling that indicated that the concentration of PCBs in surface sediment was declining over time and would be at or below the ROD cleanup goal of 1 mg/kg in all areas of OU2 within a period of ten years. EPA is in the process of completing its five year review of the ROD that includes additional sampling and modeling. Fish and Corbicula clams have been sampled annually for over ten years as part of the CERCLA process and these data have been reviewed qualitatively by others with mixed results. This poster presents a multiple linear regression analysis of the fish data. The results of the MLR analysis indicate significant trends of decreasing concentrations of PCBs in channel catfish and largemouth bass at all locations, but no statistically significant temporal trend of PCBs in hybrid bass. Inter-species differences in bioaccumulation patterns may be attributable to differences in the life histories of the fish and these factors are explored.
Key words: bioaccumulation, monitored natural recovery, polychlorinated biphenyl, lake hartwell