Early in 1999, Brookhaven National Laboratory (BNL) will ask the community for input on cleanup alternatives for contaminated soils at the lab site. This public meeting will cover information from three documents relating to BNL soil contamination that are being released simultaneously for public review and comment. These documents are the Operable Unit II/VII Remedial Investigation Report, the Feasibility Study Report- Operable Unit I and Radiologically Contaminated Soils, and the Operable Unit I Proposed Plan. A 30-day public comment period will be held on these documents.
Operable Unit I
Operable Unit (OU) I covers areas in the southeastern portion of the BNL site, including the lab's former Hazardous Waste Management Facility (HWMF). In this area of BNL, the principal contaminants are cesium-137 and strontium-90. Low levels of other radionuclides and heavy metals (such as lead and mercury) have been found in a few locations.
The greatest area of concern is the former HWMF, where the highest levels of cesium-137 have been detected. This facility was used from 1947 - 1997 for processing, storing and shipping radioactive wastes, and from 1979 - 1997 for processing, storing and shipping hazardous wastes.
Radiological contamination has also been found at and near the Reclamation Facility, which was used to clean radioactive material from clothing and equipment.
An incinerator ash landfill contains contamination including both radioactive materials and heavy metals.
The Meadow Marsh ponds and two storm recharge basins serve as breeding grounds for the endangered tiger salamander. Heavy metals and organic chemicals have been found at these locations.
Operable Unit II/VII
The areas covered by Operable Unit II/VII include the Waste Concentration Facility, which was used to store and process liquid radioactive waste, as well as several lawns and landscaping soils near BNL buildings. These areas were identified by aerial radiation surveys and later studied using soil sampling and analysis to search for any contamination.
The only soil contaminants found in these areas were radiological, mainly cesium-137. These contaminants were found in the top layer of soil, less than two feet below the surface. Soils deeper than two feet were not contaminated, except for one location where tritium and sodium-22 were found. No chemical contaminants were found in these areas.
The primary contamination in OU II/VII is found in the soils. Therefore, the soils of OU II/VII were incorporated into OU I to facilitate plans for cleanup.
Cleanup options
Several alternatives are being proposed to address the radiologically contaminated soils:
Preferred options
The third alternative, excavation and off-site disposal of radiologically contaminated soils, is being recommended by the N.Y. State Department of Environmental Conservation, the U.S. Environmental Protection Agency and the U.S. Department of Energy. The agencies determined that this alternative would be most protective of human health and the environment because all radiologically contaminated soils above cleanup levels would be removed. Excavated soils would be disposed at a licensed off-site facility, so no on-site maintenance and inspection would be required.
Removal of contaminated soils and reconstruction of wetlands are proposed for the Meadow Marsh basins, a known breeding area for tiger salamanders. Continued monitoring is proposed for the storm recharge basins, which have lower levels of contamination.
Public comment is encouraged on all of the cleanup options discussed above. The final remedies chosen could be any one or a combination of the options, depending on public comments and any additional technical information. After community input is gathered, a final decision will be made by the regulatory agencies and the cleanup will begin.
Other areas of contamination, such as 55 former waste pits and all three on-site landfills, have already been addressed. The on-site landfills have been capped to keep out rainwater that could move contamination into the groundwater. The waste pits have been excavated to remove their contents. The materials removed have been sorted and are being disposed of off-site.