The contamination will be removed in a two-phase project.
By Bill Bartleman firstname.lastname@example.org
The first phase of the work on the North-South Diversion Ditch involves installing new piping to divert water from the ditch into lagoons and eventually to a treatment plant. A basin also will be built to handle large amounts of water after the ditch is plugged so that no runoff can leave the plant site.
The second phase involves excavating contaminated soil from the ditch. Department of Energy officials estimate that 90 percent of the soil will be disposed of in the plant's landfill if the Kentucky Natural Resources Cabinet modifies the landfill permit.
The work will cost about $12 million and be completed by December 2003, according to Gordon Dover, Paducah projects manager for Bechtel Jacobs, which is overseeing the work for DOE.
The ditch is contaminated with radiation and toxins from the C-400 building, which for years was where production equipment was cleaned with trichloroethylene, a chemical that has been linked to cancer.
Officials say that a broken drain in the building resulted in water contaminated with trichloroethylene and radiation leaking under the building and into the ditch. It has contaminated a groundwater plume and residential wells outside the plant that have been taken out of service.
Dover said all the soil taken from the ditch will be tested for contamination, and only what is below Environmental Protection Agency levels will be disposed of in the landfill. The rest will be shipped to an off-site hazardous waste landfill.
State regulators in the past have rejected the idea of disposing of any of the soil in the landfill because of the contamination. DOE, however, contends that 90 percent of the soil can be placed in the landfill, with the state's consent, because tests will show levels below what is allowed by the EPA.
Dover hopes the issue can be resolved before excavation begins in the spring. Requiring all the soil to be taken to an off-site facility would greatly increase the cost, according to previous comments by Don Seaborg, DOE's Paducah site manager.
After the soil is excavated, the ditch will be restored with a two-foot clay cover topped with about two feet of clean soil and grass, according to DOE's plans.