The hydrogeologic setting in this region consists of surficial unconsolidated material and an underlying fractured bedrock system. The stratigraphy at the site consists of 5 to 30 feet of sand and gravel fill, 20 to 30 feet of sand and gravel glacial deposits, and then 5 to 10 feet of till overlying the bedrock. The surficial fill is typically unsaturated, but the underlying stratified unconsolidated glacio-fluvial or glacio-lacustrine material is a water-bearing zone. The depth to the water table aquifer fluctuates up to
10 feet seasonally. Groundwater flow in this unit is toward the Passaic River in a general southwest direction. Hydraulic conductivity for this unconfined aquifer is estimated to be 30 feet per day (ft/day), and the transmissivity is estimated at 750 ft2/day. Till material underlying the unconsolidated aquifer consists of silty sand and gravel which can potentially act as an aquitard.
The bedrock formation underlying the unconsolidated material is known as the Passaic Formation, formerly designated as the Late Triassic Brunswick Formation. The bedrock consists of interbedded red/brown sandstone and mudstone. The bedrock does not outcrop at or near the Clariant site. Bedding
in the vicinity of Clariant strikes about six degrees east of north, and dips about seven degrees westerly. The top 30 to 50 feet of the bedrock is fractured, and flow within these fractures is generally to the southwest. Primary porosity in the Brunswick Formation is negligible, but bedrock groundwater flow does appear to occur within fractures and along bedding planes. According to the most recent bedrock groundwater evaluation, flow in this unit ranges from south to southwest as it travels off site. The vertical groundwater gradient in the shalllow bedrock is up.
Targeted Environmental Media:
 Dense Non-aqueous Phase Liquids (DNAPLs) - Fractured Bedrock
The horizontal extent of the ODCB-SM/VOC groundwater plume has been estimated to be approximately 350 feet by 500 feet extending to the downgradient edge of the property along the Passaic River.
Major Contaminants and Maximum Concentrations:
- Chlorobenzene (35,000 µg/L)
- 1,2-Dichlorobenzene (353,000 µg/L)
- 1,3-Dichlorobenzene (765 µg/L)
- 1,4-Dichlorobenzene (4,720 µg/L)
- Methyl tert butyl ether (2,000 µg/L)
- Tetrachloroethene (16 µg/L)
- Trichloroethene (14 µg/L)
- Methylene chloride (12 µg/L)
- Chromium (221 µg/L)
No technologies selected.
- Pump and Treat
Comments:
The concentrations given in the table above are for 1996 for chlorobenzene and 1,2 dichlorobenzene and 2004 for the remainder.
The pump and treat system became operational in 1995.
New Jersey Groundwater Quality Standards such as PCE and TCE equal to 1 ug/L.
The concentrations in the plume and treatment influent have been declining but are still above cleanup goals.
Thought is being given to using chemical oxidation for treating hotspots,
http://www.epa.gov/region02/waste/fsclaria.htm
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