The landfill is situated along a central anticline running north and south. The core of this anticline is comprised of the Tonoloway Formation, a Silurian Age formation composed of medium gray, thinly bedded to massive limestone. It is believed that the Tonoloway Limestone underlies the entire site to great depths. The Tonoloway is bounded on either side by synclinal structures composed of limestone. The upper section is interbedded with shale, and the basal section contains nodular and cherty limestone. The old port formation is composed of an upper member, Ridgely Sandstone, and a lower member, Shriver Shale. The Ridgely Sandstone is a fine-grained sandstone with silty siltstone. The Shriver Shale is a massive calcareous dark gray shale.
The site subsurface is generally composed of a minimum four-foot-thick clay loam over a natural sandy loam to loam material ranging from several feet to 20 feet thick. Beneath the loam lies fractured bedrock including limestone, shale, sandstone, and siltstone. While the bedrock types generally have low porosity, the extensive joints and bedding planes can increase secondary porosities to greater than 20 percent. The depth to static water level ranges from several feet in the northeast to over 100 feet in the majority of the landfill area. Thus, the ground water flow is predominantly in the bedrock. piezometric and pumping test data indicate that the aquifer behaves as a single unconfined unit.
Targeted Environmental Media:
 Fractured Bedrock
Not given in ROD or five-review reports.
Major Contaminants and Maximum Concentrations:
- Tetrachloroethene (Not given)
- Trichloroethene (37 µg/L)
- 1,2-Dichloroethene (1,050 µg/L)
- Vinyl chloride (410 µg/L)
- 1,1-Dichloroethane (135 µg/L)
- 1,2-Dichloroethane (Not given)
- Chloroform (Not given)
No technologies selected.
- Pump and Treat
Comments:
The contaminant levels given above are estimates from graphs contained in the 2006 Five-Year Review.
There are six extraction wells that became operational in 1996 with three more added later. The original system had dischared treated water to a surface water. This was changed by an 1995 ESD to discharge to a POTW.
Cleanup goals were set at MCLs.
The system continues operation. Contaminant trends in the recovery wells are flat with one indicating an increase. Contaminant trends in perimeter monitoring wells have concentrations going below MCLs or detection limits indicating the plume is contained.
http://cfpub.epa.gov/supercpad/cursites/csitinfo.cfm?id=0301982
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