A 10 ft layer of artificial fill overlies fractured bedrock. Ground water is 8 to 9 ft. bgs.
Targeted Environmental Media:
 Dense Non-aqueous Phase Liquids (DNAPLs) - Fractured Bedrock
Major Contaminants and Maximum Concentrations:
- Trichloroethene (88,000 µg/L)
- Vertical Chemical Profiling
- Other
Comments:
Pump test to determine interconnection of fractures.
- Fracturing
Comments:
In the 2002 pilot test, the geologic matrix was pneumatically fractured and then a high purity micro scale iron powder was injected into four boreholes to treat soil and ground water to about 30 ft below ground surface. The zero valent iron slurry is delivered in a liquid atomized form using nitrogen gas as a carrier fluid. Each well treated about a 25' radius in the fractured rock area. A total of 16,000 lbs of iron was injected during the pilot test.
Source zone remediation
Within three months of the pilot injection, ground water concentrations of the target CVOC compounds had been reduced by 95-99%. Monitoring wells outside and below the pilot test area showed little evidence of contaminant migration outside the treatment area.
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