It’s been more than 10 years since Lewis County first identified chemical contamination in an aquifer that sat below its Central Shop on Forest-Napavine Road and provided water to surrounding residents.

    Since then, the county has paid one resident more than $200,000 as a settlement and hooked a total of nine households to city water after wells in that area along Jackson Highway near North Fork Road were found to have chemicals above federal standards.

    More than 590 tons of contaminated soil — the likely result of a truck washing station that released solvent on the site decades ago — has been removed and the aquifer has been treated periodically.

    Now, the county has agreed to continue efforts to monitor and treat the water source for at least the next ten years. The Lewis County Commission agreed to a renewed deal with the Washington State Department of Ecology during its regular meeting Monday.

    Under the deal, the county has agreed to monitor and treat the aquifer. The commission also voted to renew its contract with a consultant to conduct the work. Lewis County Central Services Director Mike Strozyk said he expects the county to monitor the situation in-house after 2010.

    The renewed agreement comes as both Ecology and Lewis County officials claim success in dealing with the contamination a decade after it was identified.

    In 1998, routine water testing revealed the presence of industrial solvents in the groundwater at the Lewis County Central Shop. Later testing found traces of tetrachloroethene and trichloroethene in several wells nearby. These chemicals can cause cancer over long periods of time.

    Since then, the county and Ecology have spent close to $1 million, according to Strozyk. Through a grant, Ecology has covered 75 percent of the total costs thus far. The commission on Monday accepted another $450,000 to be used over the next two years. The county’s match will be $112,000.

    Ecology Site Manager Guy Barrett said the efforts of the two entities over the past ten years have resulted in a largely repaired water source, though a cloud of contamination still remains.

    “I think this is going to be a success story,” he said Monday.

    Barrett, the second manager to oversee the project, said the use of permanganate has significantly reduced the levels of contaminants in the groundwater, and the continued treatment could bring the cleanup to fruition within 11 years.

    He said Lewis County’s contaminated site is not unique. Ecology lists dozens of similar sites across the state on its Web site, and Barrett said that many dry cleaners have caused similar contamination over the years.

    The question of when the contamination actually occurred has not been answered.

    “This could have been going on in the ‘70s, ‘80s, maybe even in the ‘50s,” Strozyk said.

    Barrett agrees. He said it was likely the result of washing trucks on the property — perhaps in the ‘50s or ‘60s — which resulted in the leakage of solvent into the aquifer over time.

    The facility south of Chehalis has been used by the county since the late 1950s for general automotive repair and maintenance, equipment washing and storage.

    Sometime during that span, solvent, benzene compounds and tetrachloroethene seeped through the ground and into the aquifer.

    Strozyk said that he’s pleased with the progress that has been made, and is confident the issue is on the road to being resolved.

    “We’re very comfortable with where we’re at,” he said. “We’ve made significant progress.”