EPA to Review Cleanup Progress at Gilson Road Site in Nashua, NH

Release date: 08/24/04

Contact Information:

Contact: Peyton Fleming, EPA Public Affairs Office, 617-918-1008

Darryl Luce, EPA Project Manager, 617-918-1336

For Immediate Release: August 24, 2004; Press Release # 04-08-14

BOSTON --The U.S. Environmental Protection Agency announced today that it will review the effectiveness of ground water treatment remedies in place at the Sylvester Superfund Site, also known as the Gilson Road site, in Nashua, NH.

The study, called a five-year review, will ensure that soil and ground water treatment remedies are protecting the public health and environment. This is the third five-year review for the Gilson Road site.

In a 1982 “record of decision,” EPA called for construction of a slurry wall around the site and a cap over the site to contain the most contaminated ground water. During this time, the City of Nashua connected potentially affected homes to a municipal water source and fenced in the property. After a second record of decision in 1983, EPA built a ground water treatment plant, which operated for 10 years between 1986 and 1996. During this time, more than 1.5 billion gallons of ground water were treated and 216 tons of contaminants were removed from the ground water.
Since the water treatment plant stopped operating in 1996, EPA and the NH Department of Environmental Services have been monitoring the concentrations of contaminants in ground water and surface water at the site. Ground water at the site is not now used for drinking water, but concentrations of organic and inorganic chemicals in the ground water, although reduced, remain at levels above health-based standards for drinking water consumption.

EPA will examine the protectiveness of the existing conditions at the site. EPA’s team is reviewing reports prepared by the state and is:

• interviewing site workers and local officials;
• collecting information from local officials (zoning changes);
• reviewing monitoring reports to evaluate how cleanup levels are being met;
• conducting site visits to inspect the remedy components;
• assessing records and reports.