EPA to study Superfund site (5/6/10)

May 6, 2010

By Greg Duggan

Observer staff

The Environmental Protection Agency has scheduled meetings with the community this week to discuss the status of a Superfund site on Commerce Street in Williston.

A plume of so-called volatile organic compounds rests underground in an area that extends from Commerce Street to South Brownell Road. The federal EPA plans to spend the spring and summer delineating the extent of the contaminated area, said remedial project manager Karen Lumino.

Meetings with affected landowners were scheduled for Wednesday evening, after press deadline, and Thursday morning. Lumino said the meetings would cover the history of the contaminated site and preview upcoming work, while giving attendees a chance to ask questions.

Based on information from the EPA, a groundwater study conducted by the state in 1999 and 2000 showed the contaminated plume originating at the northern end of Commerce Street and spreading to the south. The area became a federal Superfund site in 2005.

The plume contains high concentrations of trichloroethylene, tetrachloroethylene and BTEX compounds — benzene, toluene, ethylbenzene and xylene. According to the Agency for Toxic Substances and Disease Registry, trichloroethylene is used as a solvent for cleaning metal parts; inhaling or drinking large amounts of the chemical can cause nervous system effects, liver and lung damage, abnormal heartbeat, coma and death. Tetrachloroethylene is used for dry cleaning and metal degreasing, and exposure to high concentrations can cause dizziness, headaches, sleepiness, confusion, nausea and death.

Because the buildings in the area use municipal water rather than wells, the EPA believes there are no health risks from the contaminated groundwater. The agency plans to confirm that belief with its work this summer, and will also test for vapors of the chemicals. Lumino said the EPA does not feel the site requires immediate action.

Instead, the EPA plans to take groundwater samples from more than 20 wells in the area that had been installed for testing. Lumino said the agency will then see how those samples have changed since 2008, the last time tests were done. New wells could also be drilled for more tests.

“One of the goals we hope to achieve with the additional work this summer is to get a better handle on the groundwater plume,” Lumino said.

After delineating the plume and hopefully determining a source, the EPA will conduct a risk assessment, looking at exposure points for humans and the environment. If health risks exist, Lumino said, the EPA will conduct a feasibility study to determine a remedy to the problem. The entire process could take three to five years, Lumino said.

Lumino said solutions could range from digging up the area or sucking out the contaminants to imposing institutional controls on properties in the area, such as forbidding drinking wells. Another possibility, if it’s deemed safe, is to do nothing.

Regardless of the outcome of the studies, Lumino said the EPA will present its plan to the public when one is established.

“No one here is drinking the groundwater,” Lumino said. “That gives us a little breathing room. The site will be addressed, but there’s no imminent threat.”