Subsurface soils consist of silty clays to depths ranging from 10 to 60 feet. The clays are underlain by limestone and dolomite of the Epler Formation, Beekmantown Group. Groundwater flow occurs in secondary porosity along solution channels or bedding and fracture planes in the rock. Groundwater is encountered approximately 90 feet below ground surface.
Targeted Environmental Media:
 Fractured Bedrock
The total site area exceeds 8 acres.
Major Contaminants and Maximum Concentrations:
- Tetrachloroethene (402 µg/L)
No technologies selected.
- Flushing (In Situ)
- Chemical Oxidation (In Situ)
- Soil Vapor Extraction
- Bioremediation (In Situ)
- Other (ART In-Well Technology)
Comments:
The ART In-Well Technology combines in situ air stripping, air sparging, soil vapor extraction, enhanced bioremediation/oxidation, and subsurface circulation and flushing in a wellhead system. The system is designed to accommodate a 4-inch well.
In May 2002, two existing 4-inch wells were retrofitted with the ART In-Well Technology. A third well was installed 50 feet upgradient of the compliance monitoring point. The system began operation in August 2003.
Cleanup goals are the Pennsylvania action limits for tetrachloroethene (PCE) (5 µg/L).
The concentration of PCE as of January 2004 was 16.5 µg/L. Analytical testing in April 2004, 9 months after startup of the system, indicated that PCE concentrations were reduced to below the action limit. The system remained in operation and concentrations have been reduced further.
The client has received a Relief of Liability letter from the Pennsylvania Department of Environmental Protection (PADEP) (Re: Jerry Olenick PADEP 570-826-2498).
This case study demonstrated that the ART In-Well Technology is an effective alternative technology that is capable of stimulating site remediation and significantly reduces VOC concentrations over a short time at fractured bedrock sites.
Reference:
http:www.clu-in.orgproductstins : The ART In Well Technology: An Effective and Cost-Efficient Remedy for Soils and Groundwater in Fractured Bedrock Formations. From Pucke, Steve; Marco Odah; Charles Reed. Proceedings: 2004 U.S. EPANGWA Fractured Rock Conference: State of the Science and Measuring Success in Remediation, Portland, Maine, 13-15 September 2004. p 59-67, 2004. Available at: http:www.clu-in.orgproductssiteprof2004fracrockconfcdr_pdfsindexedgroup1059.pdf
|
