Superfund Site Profile

Thermal remediation using Electrical Resistance Heating technology was completed in November 2016.  Approximately 5,000 ponds of tetrachloroethylene (PCE) were removed from the subsurface.


The South Municipal Water Supply Well Superfund site is located in Peterborough, New Hampshire. Installed in 1952, the South Municipal Water Supply Well provided water to Peterborough for nearly 30 years. On October 22, 1982, the New Hampshire Water Supply and Pollution Control Commission (now the New Hampshire Department of Environmental Services) found over 100 parts per billion of total volatile organics in a sample of water from the South Well.  At the recommendation of the EPA and the State, the Town of Peterborough discontinued the use of the South Well in December 1982.  Subsequent investigations determined that solvent use and disposal at the NHBB facility had resulted in a plume of contaminated groundwater extending from under the NHBB property to the vicinity of the South Well.  The principal solvents NHBB had used and that were detected in the groundwater were tetrachloroethylene (PCE), trichloroethylene (TCE), and 1,1,1-trichloroethane (1,1,1-TCA). The Site was added to the National Priority List on September 21, 1984.

The approximately 250-acre Site has been defined to include the South Municipal Water Supply Well (South Well), nearby commercial and residential properties along Sharon Road, a portion of the Contoocook River and U.S. Route 202, the adjacent wetlands, and the New Hampshire Ball Bearings (NHBB) property, which is located approximately two miles south of the center of the town of Peterborough in Hillsborough County, New Hampshire.  The NHBB facility is situated approximately 1,200 feet west-northwest of the South Well and approximately 800 feet west of the Contoocook River. The NHBB property currently consists of an active manufacturing facility, asphalt parking lots, the groundwater treatment system, and sedge meadow wetlands. 

The Site is situated in the Contoocook River Valley, on glacial/fluvial deposits ranging from approximately 20 to over 100 feet in thickness.  Deposits are predominantly sands and gravels, although silty layers are found dispersed both vertically and horizontally throughout the Site.  The general direction of groundwater flow is east-northeast in the vicinity of the NHBB plant and changes to a more northerly direction in the vicinity of the Contoocook River.

Land use in the vicinity of the Site, particularly east of the Contoocook River, is rural and undeveloped.  A fitness center and several apartments are situated adjacent to, and south of, the NHBB property.  Commercial establishments are located approximately 1,000 feet north and northwest of the South Well.  Residences are located to the west of the NHBB property along Old Jaffrey Road and two residences are located proximate to the Contoocook River along Sharon Road.

The Site and adjacent area are served by a municipal water system which receives water from three wells located north of the town center.  The closest residential wells are located approximately one-half mile north of the Site.