The geology at the Site consists of an uppermost overburden unit consisting of heterogeneous fill composed of various materials ranging from silty clay to coarse gravel and cobbles. Generally, the thickness of the fill is approximately 10 feet in the vicinity of the former main building. The underlying unit is composed of water saturated, silty fine sand, with a varying thickness from only a few feet to almost 30 feet in the (project)
northwest corner of the Site. Underlying the silty fine sand unit is till/weathered bedrock, ranging from
approximately 2 to 10 feet thick. The till is a reddish-brown clay or silt, derived from the Passaic Formation.
The till is very dense and can contain large rock clasts or pebbles of gneiss, quartzite, sandstone, and quartz.
The upper surface of the bedrock tends to be weathered with clay filled fractures alternating with seams of
competent rock and silty clay. The depth to bedrock ranges from approximately 20 to 50 feet below land
surface. The bedrock elevation is highest in the central portion of the Site. All strike and dip values show a
very similar trend, northeast-southwest strike and gentle northwest dip. Groundwater at the Site exists in the
overburden, shallow bedrock, and deep bedrock. The average depth to ground- water at the Site is between 10 to 40 feet bgs.
Shallow bedrock was defined to be approximately the upper 30 feet of the bedrock. Similarly to the overburden groundwater, localized depressions in the water table are due to the pumping associated with the interim free product recovery system for LNAPL and installation of the containment system. Outside the pumping influences, groundwater flow conforms to the regional flow towards the southeast
Targeted Environmental Media:
- Fractured Bedrock
- Light Non-aqueous Phase Liquids (LNAPLs)
The intermediate bedrock aquifer is contaminated and extends to 100 feet bgs. The lateral extent is not given.
Major Contaminants and Maximum Concentrations:
- Trichloroethene (380 µg/L)
- 1,2-Dichloroethene (450 µg/L)
- Vinyl chloride (170 µg/L)
- Tetrachloroethene (44 µg/L)
- 1,1,1-Trichloroethane (36 µg/L)
- 1,1-Dichloroethane (200 µg/L)
- 1,1-Dichloroethene (82 µg/L)
- Borehole Geophysics
- Vertical Chemical Profiling
- Pumping Tests
- Pump and Treat
- Other (Monitored Natural Attenuation in overburden and shallow bedrock)
Comments:
Concentrations for the shallow bedrock above are from 2003/2004.
The pump and treat system was operated to recover LNAPL in the overburden and shallow bedrock.
Cleanup levels are the New Jersey Groundwater Quality Standards.
The site is in long term monitoring and has been redeveloped into a golf course.
http://www.epa.gov/region02/waste/fshyatt.htm
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