Characterization and closure of the Met Lab Carolina Bay at the Savannah River site, Aiken, South Carolina

The Met Lab Carolina Bay is subject to Subtitle C of RCRA and CERCLA requirements. Located in the northwestern section of the Savannah River Site, the Met Lab Carolina Bay is a marshy, oval-shaped natural depression covering approximately six acres. The Carolina Bay received wastes from three sources: the Met Lab Basin A-007 drainage outfall, the A-Area coal-fire power plant A-008 drainage outfall and the A/M-Area vehicle maintenance parking lot stormwater runoff A-009 outfall. Two characterization efforts conducted in 1988/89 and 1991 indicate the presence of metals in the sediments and soils of the bay. The greatest concentrations of the metals and organics being in the north-central portion of the bay. The metals and organics were primarily associated with surface sediments and the organic-rich soil layer to a depth of about two feet. Conclusions from the Human Health Baseline Risk indicate the future on-unit resident exposure to sediments and soil poses an unacceptable level of risk to human health. However, the assumptions built into the calculations lead to conservative human health risk findings. A qualitative Ecological Risk Assessment was performed on the Carolina Bay. This ecological assessment, based on historical and existing sampling data, was found to be insufficient to more » make a definitive decision on the contaminants` effects on the ecology of the bay. The proposed action for the Carolina Bay is to conduct an ecological characterization. It appears that the ecological risks will be in the driving factor in determining the remedial action for the Met Lab Carolina Bay. « less