Washington's Department of Ecology is asking for public input on plans to partially clean up contaminated soil and ground water at the old Pasco Sanitary Landfill.
About 30,000 drums of waste and many tons of bulk chemical wastes were buried at the landfill from 1972-74.
The landfill, on Dietrich Road by the intersection of Kahlotus Road and Highway 12, was listed as a federal Superfund cleanup site in 1990 because the drums had deteriorated and were leaking chemicals into the surrounding soil, according to Ecology officials.
About 5,000 drums of herbicide-manufacturing wastes were removed in 2002, but the remaining drums continue to leak other types of chemicals, including plywood resin wastes, wood treatment wastes, lime sludge, solvent wastes and more, the agency said.
Those chemicals slowly are making their way to the ground water beneath the landfill. Water samples from monitoring wells show that ground water contamination extends from the landfill to at least as far south as "A" Street, a distance of about two miles, Ecology officials said.
Use of well water within the contaminated area is restricted, so the city supplies water to homes and businesses in that area.
Studies completed in 1999 identified acetone as the contaminant of most concern in the soil at the landfill. They also identified chromium and several volatile organic compounds, including vinyl chloride, tetrachlorethlyene and dichloroethylene, as the contaminants of most concern in the ground water.
More cleanup work at the landfill is intended to help keep more contaminants from entering the ground water and to remove the contaminants already there, Ecology said.
The proposed work includes upgrading the existing soil-vapor extraction system, which is meant to better capture chemicals being released into soil before they reach ground water, Ecology said. Also proposed is construction of an enhanced protective cap to replace a temporary cover in the area where the herbicide wastes were removed.
More than 40 government agencies and companies have been identified as the parties who are liable for the cleanup, the agency said.
The public is being asked to review and comment on the work plans and associated documents through Aug. 10.
Documents that are available for public comment are at the Pasco branch of the Mid-Columbia Library, 1320 W. Hopkins St., or through Ecology's website: ecy.wa.gov/programs/tcp/sites/pasco/pasco_lf_home.html
Comments and technical questions can be submitted to Chuck Gruenenfelder, project manager, Toxics Cleanup Program, Washington Department of Ecology, 4601 N. Monroe, Spokane, WA 99205; or by e-mail at email@example.com.