KEARSARGE METALLURGICAL CORP.
On this page:
- What Is Being Done to Clean Up the Site?
- What Is the Current Site Status?
- Activity and Use Limitations
- Operable Units (opens new page)
- Cleanup Progress (opens new page)
The 9-acre Kearsarge Metallurgical Corporation (KMC) is located in Conway, New Hampshire on the north shore of Pequawket Pond. KMC made precision stainless steel castings on site from 1964 until the company went out of business in 1982. The manufacturing process produced castings using the lost-wax process. That process created waste casting sands, wax and solvents that KMC dumped in a wooded wetland just east of the facility. Investigations conducted by the New Hampshire Department of Environmental Services (NHDES) and EPA after KMC ceased operations showed that in addition to a large pile of mixed casting sands and solvents, groundwater at the Site was contaminated with volatile organic compounds (VOCs), predominantly 1,1,1-trichloroethane (1,1,1-TCA), and its breakdown products, particularly 1,1-dichloroethene (1,1-DCE).
EPA investigated the Site and issued a cleanup decision in September 1990 splitting the remedy into two efforts: removing the surficial source materials, and then addressing the groundwater through a pump-and-treat remedy. EPA completed the source control remedy in September 1992, removing 13,620 tons of waste pile material, 41.85 tons of crushed drums, a solvent-contaminated septic tank and 12 yards of contaminated septic soils.
EPA built the groundwater treatment plant in 1993, and NHDES operated it until 2005. The extraction system cleaned up all groundwater contaminated from the Site on the west side of Hobbs Street by 2003. The east side, where the waste pile had lain, significant contamination remained in soils and groundwater.
To address these soil issues, EPA funded, and NHDES contracted, a soil excavation effort in the affected area. From October through December 2003, NHDES contractors excavated, dewatered, and disposed of 5,670 tons of soils contaminated with chlorinated solvents from the east side. NHDES then filled the excavated area with gravel and installed a new extraction well, EW-13B. Pumping and treating of water from this area began in February 2004 and continued until December 2005.
In December 2005, EPA and NHDES agreed that contaminant concentrations had declined significantly in the culvert area and discontinued pumping to assess the potential for a rebound of contamination. Ultimately, EPA and NHDES determined that contaminant concentrations were not abating. NHDES then designed and implemented a soil mixing / soil treatment remedy in fall 2015.
What Is Being Done to Clean Up the Site?
EPA has conducted several five-year reviews that document conditions at the Site. These reviews ensure that the remedies put in place protect public health and the environment, and function as intended. The most recent review concluded that response actions taken at the site are in accordance with the remedy selected by EPA, and that the remedy continues to be protective of human health and the environment in the short term. Continued long-term protectiveness of the remedy requires ongoing monitoring of the Site’s institutional controls and continued groundwater monitoring.
What Is the Current Site Status?
The 1992 removal, the eleven years of pumping and treating groundwater, the 2004 soil removal and the 2015 soil mixing / soil treatment remedy have addressed all Site contaminants. Currently, NHDES is monitoring groundwater at the Site to determine the effectiveness of the 2015 soil mixing / soil treatment remedy in destroying the remaining contamination at the Site.
The Town of Conway took ownership of the property on August 27, 2012. In December 2012, the Town removed the eastern, dilapidated section of the old KMC building, and left intact the structurally sound and newer, eastern wing of the building. The Town also removed the contents of the former groundwater treatment plant and auctioned the property to a local business. Presently there is a towing company and a heating & air-conditioning business operating at the former KMC building, and a truck repair shop operating in the former groundwater treatment plant.
Activity and Use Limitations
At this site, activity and use limitations that EPA calls institutional controls are in place. Institutional controls play an important role in site remedies because they reduce exposure to contamination by limiting land or resource use. They also guide human behavior. For instance, zoning restrictions prevent land uses – such as residential uses – that are not consistent with the level of cleanup.
For more background, see Institutional Controls.
Institutional controls are required for this site.
This site requires ICs because a decision document, such as a Record of Decision, has documented some level of contamination and/or remedy component at the site that would restrict use of the site. These ICs are required to help ensure the site is used in an appropriate way and that activities at the site do not damage the cleanup components. These ICs will remain in place for as long as the contamination and/or cleanup components stay on site. The matrix below is a general summary of the restrictions at this site at the date of this report. The information in this matrix is a general description of the restrictions at the site only. The site contacts should be consulted if there are questions on the ICs for this site.
The following IC Instruments provide media-specific use restrictions that have been implemented by EPA for protecting human health, the environment and remedial engineering on this site. Instruments are documents used by EPA or other organizations to implement the use restrictions at a site. To know about other media-specific use restrictions that are planned but not implemented at this site, please contact the Regional Office using the Site Contact listed above. Note that where multiple entries occur, it will impact more than one pathway.
Click here for IC Instruments implemented for this site. http://semspub.epa.gov/src/collection/01/SC31715
ICs are generally defined as administrative and legal tools that do not involve construction or physically changing the site. Common examples of ICs include site use and excavation restrictions put in place through State and local authorities like zoning, permits and easements. ICs are normally used when waste is left onsite and when there is a limit to the activities that can safely take place at the site (i.e., the site cannot support unlimited use and unrestricted exposure) and/or when cleanup components of the remedy remains onsite (e.g., landfill caps, pumping equipment or pipelines). Effective ICs help ensure that these sites can be returned to safe and beneficial use.
Disclaimer: This information is being provided by EPA as an informational tool to further assist the public in determining the types of restrictions that may be in place at National Priorities List sites being addressed by EPA under the Superfund program. In addition to the areas addressed by the institutional controls identified on this web site there may be other areas on the property that require restrictions on use of the property that are not captured in this EPA database. States and other entities may have implemented laws or restrictions applicable to this site. The information provided herein does not replace a title search or meet "All Appropriate Inquiry" requirements. U.S. EPA encourages users to review the Site files to obtain information regarding remedy components, containment systems and the land use for which cleanup standards were selected for these sites. More information and links can be found in the Institutional Control instrument collection of document, above, and the EPA regional offices may also be contacted.
During cleanup, a site can be divided into a number of distinct areas depending on its complexity. These areas, called operable units (OUs), may address geographic areas, specific problems, or areas where a specific action is required. Examples of typical operable units include construction of a groundwater pump and treatment system or construction of a cap over a landfill.