The site is composed of Silurian dolostones and shales, which have little primary porosity. Ground water flows through secondary porosity features, including joint sets and bedding planes. Hydraulic conductivity of the fractured bedrock was calculated to range between 10-3 and 10-6 centimeters per second (cm/s).
Targeted Environmental Media:
 Fractured Bedrock
Major Contaminants and Maximum Concentrations:
- Tetrachloroethene (0 µg/L)
- Trichloroethene (0 µg/L)
- cis-1,2-Dichloroethene (0 µg/L)
- trans-1,2-Dichloroethene (0 µg/L)
- Vinyl chloride (0 µg/L)
- Other
- Bioremediation (In Situ)
- Reductive Dechlorination (In Situ Bioremediation)
Comments:
Emulsified vegetable oil in the form of Edible Oil Substrate (EOS)TM was applied using 24 bedrock injection wells in a 4,000-square-foot area. The injection wells were 4 inches in diameter and approximately 40 feet deep. The overburden was 15 feet thick and was cased off. A packer assembly and pump were used successfully to inject and distribute stoichiometric doses of EOSTM throughout the fracture network. Baseline samples were collected before the injection event. After injection, ground water samples were collected every quarter for 1 year.
The goals of the test were to evaluate the impact of emulsified vegetable oil, EOSTM, on concentrations of chlorinated hydrocarbons in the off-site plume of dissolved-phase contaminants in ground water within a fractured bedrock aquifer and to develop a basis for full-scale design.
The first quarterly sampling event indicated accelerated dechlorination of tetrachloroethene (PCE) and trichloroethene (TCE) in the pilot area, with increases in concentrations of c-1,2-dichloroethene (DCE), vinyl chloride (VC), ferrous iron, methane, and trans-1,2-DCE as well. The second and third quarterly sampling events showed a decrease in concentrations of trans-1,2-DCE and cis-1,2-DCE as well as VC to below 50 micrograms per liter (µg/L). The results indicate that the contaminant concentrations have been reduced to below New York State ground water criteria. Based on the successful results, the data obtained from the pilot study will be used to develop a full-scale design for EOSTM injection throughout the plume.
EOSTM at the site induced anaerobic biological activity and promoted strong reductive dechlorination of the chlorinated solvent contamination.
References: Gutmann, Michael, Craig Pawlewski, and Vivek Nattanmai. Remediation of Dissolved-Phase Chlorinated Hydrocarbons in Fractured Bedrock Using Emulsified Vegetable Oil. The Ninth International In Situ and On-Site Bioremediation Symposium. May 7 - 10, 2007. Baltimore, Maryland.
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