Overburden material at this site consists of sand and gravel outwash, and possible kame terrace deposits of late Pleistocene age. Holocene fluvial deposits associated with the nearby Ipswich River are also present. The bedrock surface dips to the southeast; depth to bedrock varies from approximately 12 feet to > 40 feet. Bedrock at the site varies from granodiorite subjected to low grade metamorphism to weakly foliated gneiss.
Targeted Environmental Media:
 Dense Non-aqueous Phase Liquids (DNAPLs) - Fractured Bedrock
Multiple small releases/ spills of chlorinated solvents (primarily PCE) at this former dry cleaning supply company have resulted in a plume of PCE approximately 400 feet wide by at least 600 feet long.
Major Contaminants and Maximum Concentrations:
- Tetrachloroethene (7,400 µg/L)
- Vertical Chemical Profiling
- Coring
- Pump and Treat
- Soil Vapor Extraction
Comments:
The ground water pump and treat system at this site, which consists of two recovery wells, and treatment with a low profile air stripper and activated carbon, has been in operation at this site since May, 1994. The system has recently been improved by the replacement of original overburden recovery wells (originally designed for mass removal in the overburden aquifer), by bedrock recovery wells drilled to about 45 feet.
A soil vapor extraction system was originally installed in 1994 to mitigate high levels of VOCs in the vadose zone. Because recovery concentrations have leveled off the system has been run intermittently.
Altough concentrations in monitoring wells have leveled off, concentrations in a municipal well 800 ft from the site have decreased significantly.
None provided
In September, 2003, state officials are confident that the system is containing the plume. This is based on the levels in the monitoring wells and the municipal well. The SVE system will remain off for a few months to see if a rebound occurs.
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