EPA set to review Merrimack site

MERRIMACK – The Environmental Protection Agency is actively involved in Superfund studies and cleanup at 22 sites in New Hampshire, and will be begin reviews of four Superfund site cleanups this year, including New Hampshire Plating Co., in Merrimack.

The EPA plans to conduct comprehensive reviews of four National Priorities List Superfund sites by performing required five-year reviews. One of those sites also includes a federal facility.

Congress established the Superfund program in 1980. The program investigates and cleans up the most complex, uncontrolled or abandoned hazardous waste sites across the country. They also facilitate activities to return those sites to productive use.

The Superfund cleanup process goes through many phases, including considering future use and redevelopment at sites, as well as conducting post cleanup monitoring of those sites.

According to the EPA’s website, New Hampshire Plating Co. is a 13-acre site where an electroplating facility operated from 1962 to 1985. During this time, wastewater containing metals, solvents and cyanide used in the electroplating operations was discharged into drainage channels in the former building floor, flowing into unlined lagoons north of the building. Those contaminants then affected on-site wetlands, contaminated surface and subsurface soils and reached the groundwater. Operations and maintenance activities are ongoing following the cleanup.

The website also states that full-scale remedial construction activities began in the summer of 2005. This included the excavation of all remaining contaminated soils and sludge from the site, treatment of contaminated soils through chemical fixation, backfilling treated soils on site, regrading excavated areas and the construction of a two-foot soil cover system over the backfilled treated soils. Those activities wrapped up in December 2006.

The EPA expects that contaminant levels in groundwater will naturally attenuate to safe drinking water levels in 26 to 58 years. Additionally, water sampling will continue in multiple areas under the direction of the New Hampshire Department of Environmental Services until groundwater contaminant levels attenuate.