By Kirk Ross
Staff Writer

Orange County Solid Waste Management director Gayle Wilson said the county plans to quickly and aggressively deal with a plume of contaminants found in groundwater in the closed section of the Eubanks Road landfill.

Wilson said the county is waiting to hear back from state environmental officials on a plan the county developed after monitoring wells showed contaminants — including benzene and vinyl chloride — drifting east from the closed portion of the Orange County Landfill near the intersection of Millhouse and Eubanks roads.

“We plan to hit it hard,” he said. “We’re not going to spend $2,000 and then wait a year and see if it works and spend another $4,000 and wait another year.”

Wilson said the materials appear to be coming from the closed portion of the landfill on the north side of Eubanks Road. That portion of the landfill opened in 1972 and is unlined. It stopped receiving waste in 1995 and was covered in 1996. It’s closure received final approval from the state in 1998.

The closed construction and demolition landfill is also near the area were the contaminants are located but does not appear to be the source. The materials, Wilson said, are consistent with the lechate from similar landfills and are likely the result of the natural breakdown of man-made chlorinated materials.

The level of the five contaminants — benzene; 1,4-dichlorobenzene; cis-1,2-dichloroethene; trichloroethene; and tetrachloroethene — exceed acceptable state levels for groundwater quality but are lower than the maximum contaminant level under federal rules for drinking water. Levels for vinyl chloride exceed acceptable levels under both measures.

After the plume was discovered in 2007, the state’s Department of Environment and Natural Resources required that additional wells be put in, with some near the property line to track its direction and the speed at which it is moving.

Wilson said so far the wells show the contaminants do not seem to be migrating off county property.

Wilson expects to hear back from the state within six weeks to four months.
Once the county has gotten an OK from regulators, the plan is to install two injection wells, which will force a mix of water and Sodium permanganate into contact with the plume to neutralize the chemicals.

Wilson said he did not know how long the process will take to be effective since there are so many variables at work.

“Our hope is that in a matter of six months, we’ll see some serious results,” he said.