WP1 Restoration of Contaminated Sites
Ballroom E, Level 4
2:10 PM - 5:30 AM, Wednesday, 12 November 2003
Chair: Barnthouse, Larry ,
(410) A Field Test of New Tools to Evaluate Management Options for Contaminated Sediments.
Schubauer-Berigan, J, Brenner, R1, Lazorchak, J1, Lyons, T1, Foote, E2, Magar, V2, Abbott, J2, Eastep, J2, 1 U. S. Environmental Protection Agency, Cinainnati, OH, USA2 Battelle Memorial Institute, Columbus, OH, USA
ABSTRACT- Dredging, in-place treatment, capping and monitored natural recovery are the primary methods available to manage contaminated sediments. Understanding how well different approaches work in different environments is critical for choosing an appropriate approach to reduce human and ecological risks. We present the results of a field test of some new sampling devices we developed to evaluate the effectiveness of risk management strategies for PCB contaminated sediments. This work is part of a larger team effort that includes studies of sediment respiration, PCB sediment and water profiling, PCB sediment diffusion, PCB water/air volatilization, and PCB biota uptake. The work was conducted at Lake Hartwell, SC, a reservoir contaminated with PCBs and currently being managed using Monitored Natural Recovery. Commercial semipermeable membrane devices (SPMDs), combined with new in-situ sampling devices developed for this study, were evaluated and used to quantify PCB movement between sediments and overlying water. Three locations in Lake Hartwell were examined, a background site (Bkgd), a site with moderate contamination (M-N) and a site of high contamination (O). PCB movement and availability was quantified using stainless steel (SS) racks (R) designed to hold SPMDs in contact with surface sediments, SS domes (D) designed to enclose and suspend SPMDs at the sediment water interface and SS cages, deployed in the water column (W)SPMDs. Caged fish and clams were also deployed. Congener-specific PCB analysis was performed via mass spectrometry. SPMD accumulation rates were linear (W > R). SPMD PCB accumulation rates were highest at site O (D:473; R:1290; W:1607 ng/g/d) > M-N (D:194; R: 883; W: 1023 ng/g/d) > Bkgd site (D: 5; R: 16; W: 21 ng/g/d). PCBs accumulation rates were highest in the WSPMD's (1607 ng/g/d) > RSPMDs (1290 ng/g/d)> DSPMD's (473 ng/g/d). RSPMD accumulation differed with respect to site (O> M-N > Bkgd).
Key words: semipermeable membrane devices, contaminated sediments, monitored natural recovery, PCB, POP