U.S. EPA Contaminated Site Cleanup Information (CLU-IN)


U.S. Environmental Protection Agency
U.S. EPA Technology Innovation and Field Services Division

Fractured Bedrock Project Profiles

Last Updated: August 21, 2002

Point of Contact:
Dan Bryant
Geo-Cleanse International, Inc.
4 Mark Road, Suite C
Kenilworth NJ 07033 
Tel: 908-206-1250 
Fax: 908-206-1251
Email: dbryant@
geocleanse.com

Letterkenny Army Depot, Oil Burn Pit
Chambersburg, PA


Hydrogeology:

Martinsburg Shale - dark gray to black -carbonaceous and fissile - interbedded with thin layers of siltstone and sandstone. Water table in bedrock approximately 30' bgs.

Targeted Environmental Media:
  • - Dense Non-aqueous Phase Liquids (DNAPLs)
  • - Fractured Bedrock

Contaminants:

Major Contaminants and Maximum Concentrations:
  • - 1,1-Dichloroethane (89,000 µg/L)
  • - 1,1,1-Trichloroethane (1,000,000 µg/L)
  • - Tetrachloroethene (20 µg/L)
  • - Trichloroethene (20,000 µg/L)

Site Characterization Technologies:

  • - Borehole Geophysics
    • Natural Gamma
    • Caliper
    • Acoustic Televiewer
    • Other
  • - Fluid Loggings
    • Temperature
    • Conductivity/Resistivity
  • - Vertical Chemical Profiling
    • Packer Isolation
  • - Other

Comments:
acoustic velocity, variable density, vertical hydraulic gradient, horizontal gradient.


Remedial Technologies:

  • - Chemical Oxidation (In Situ)
    • Fenton's Reagent
Comments:
This was a pilot scale test. Geophysical logs and packer tests in boreholes were used to determine injector locations and contaminant characteristics of water bearing fractures.
Remediation Goals:

To determine the level of contaminant distruction in bedrock.


Status:

During the fourth post injection sampling round (1 year after the pilot study) the reductions in total VOCs ranged from 27% to 86%. Additional injectors were installed to locate the upgradient and downgradient edges of the free phase product


Lessons Learned:

Destruction of the contaminants was qualified by chloride measurements. Vigorous reaction caused the release of oxidation fluids, sediments, etc., to the ground surface in pools. Some post-injection sampling indicated increases in VOC concentrations. This could be due to turbulence from the reaction which mobilized more organics than could be destroyed by the radicals and/or because the reaction increased the temperatures which may have increased the solubility of the organic contaminants.

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