The subject property is about 70 acres and located at 355 Clouser Road, Hanover (Union Township), Adams County, Pennsylvania, in a rural and agricultural area southeast of Gettysburg. A single-family home where the owner lives is located on the subject property. The source of contamination at the Site is a 40-acre Landfill that accepted household and municipal wastes and certain types of industrial and construction debris, some of which contained hazardous substances.
Keystone Sanitation Company operated the landfill from 1966 through 1990. In 1982, in accordance with Commonwealth of Pennsylvania permitting requirements, ground water monitoring for VOCs was first conducted. VOC contamination was detected in the on-Site potable well and in a nearby spring located east of the Landfill Property.
In 1984, sampling conducted in response to complaints from local citizens identified the presence of low levels of VOCs in some residential wells. Subsequent investigations confirmed this contamination was Site-related.
In 1987, the Site was added to the National Priorities List (NPL), the list of uncontrolled hazardous substance releases that are priorities for long-term remedial evaluation and response.