Meeting Oct. 8 on Proposed Water Line for Groundwater Contamination

The New Hampshire Department of Environmental Services (NHDES) will hold a public meeting in Londonderry to address groundwater contamination recently identified in residential drinking water supply wells in the vicinity of the Tinkham Garage Superfund Site.

The Tinkham Garage Site Responsible Parties group has agreed to provide in the coming months households with impacted wells a connection to the nearby Pennichuck water line, according to a press release the U.S. Environmental Protection Agency (EPA) issued this week.

In the meantime, the State has provided impacted households with point of entry water treatment systems and/or bottled water, depending on the analysis of the water and concentrations of the compounds found.

A waterline was installed in 1983 to provide alternative water to more than 400 residents living southwest of the site.

The EPA and NHDES will hold a public informational meeting on Oct. 8 at 6 p.m. in the Merrill Conference Room on the second floor at Town Hall to discuss the details of the proposal, as well as how the agencies will be moving forward with the proposed connection.

The Tinkham Garage Superfund Site, located along Route 102 (Nashua Road) in Londonderry, covers about 25 acres of wooded land bordered by residential and agricultural land.

During the 1970s, oil, oily materials, washings from septic tank trucks and other substances were discharged on the site, according to the press release.

In May 1978, the State ordered the site owner to prevent further degradation of surface water and ground water.

In November 1981, the EPA detected chemicals in ground water at the site; and in October 1982, volatile organic chemicals were identified in surface water and ground water in areas adjacent to the site.

According to the NHDES, Methyl-tertiary-Butyl Ether (MtBE) contaminates were identified near the site last year while the agency was conducting free well water testing for contamination at homes on Bockes Road near the intersection with Mammoth Road, as well as homes near the intersection of Nashua Road and Gilcreast Road.

In the following months, the NHDES completed additional testing, where residential well impacts were found to be greater than drinking water standards.

The testing was subsidized with funds from the initial $90 million in settlements the State received from gasoline suppliers for spills at sites across the State.

Additional bedrock investigations are expected to continue through 2016 at the site.

A Draft Explanation of Significant Differences, which establishes the contaminants found in the residential area are similar to those found at the Tinkham Garage Site, has been posted on the Town website at www.londonderrynh.org.

More information is also available on the EPA’s website at www. epa.gov/region1/superfund/sites/tinkham.

See related story on page 2.