The bedrock beneath the site consists of fractured quartzite (Hardyston Formation) and crystalline limestone (Leithsville Formation) overlain by soil derived from weathered bedrock.
A large fault, which is a fracture along which two separate blocks of the bedrock have moved, exists south of the site. The fault is significant in that it separates crystalline limestone, which is also beneath the site, from red shale. As ground water moves towards the fault it may move upward and discharge at the surface in the form of springs.
Lithology of one source area monitoring well was 1-25 feet, weathered, highly fractured gray sandstone, limestone, and quartz with voids at 18-20 feet; and, 25-38 feet, highly fractured sandstone, and limestone with quartz and fault breccia. Groundwater was encountered at 3 feet in the weathered bedrock but the majority of water entering the well was from a depth of 34 to 38 feet.
Targeted Environmental Media:
 Fractured Bedrock
The plume is approximately 2,500 feet long and 300 feet deep.
Major Contaminants and Maximum Concentrations:
- Tetrachloroethene (15 µg/L)
- Trichloroethene (37 µg/L)
- 1,1-Dichloroethene (1,734 µg/L)
- 1,1,1-Trichloroethane (1,052 µg/L)
- 1,1,1-Trichloroethane (1,052 µg/L)
No technologies selected.
- Pump and Treat
Comments:
The pump and treat system became operational in 1998. It consisted of nine 8" diameter groundwater extraction wells along the eastern and southeastern perimeter of the Site to capture the contaminated groundwater plume which generally runs in a northwest to southeast direction beneath the Site. The extraction wells were installed into the bedrock aquifer at depths ranging from 250 to 350 feet and screened at depths ranging form 20 to 350 feet.
Cleanup goals are MCLs.
The system continues to run. Through May 2008 and based on the calculated average influent and effluent concentrations, approximately 27.5 pounds of the Site COCs have been removed from the aquifer since system start-up. Concentrations in pumping well influents have fallen.
http://cfpub.epa.gov/supercpad/cursites/csitinfo.cfm?id=0300602
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