In Situ Chemical Oxidation; Fenton's reagent
- Geo-Cleanse's patented process for in situ chemical oxidation using Fenton's reagent
- Fenton's reagent - hydrogen peroxide (50%) and an equivalent volume of ferrous iron catalyst were delivered via injection to the subsurface
- Total of 44 injectors - 23 for Phase 1, including deep (42 ft bgs) and shallow (32 ft bgs) injectors; 21 injectors added for Phase 2, including deep (40 ft bgs) and shallow (35 ft bgs) injectors
- Phase 1 - two injections of Fenton's reagent into the subsurface, totaling 12,045 gallons (8,257 gallons November 2-21, 1998; 3,788 gallons February 8-14, 1999) of solution were injected.
- Phase 2 - two injections of Fenton's reagent into the subsurface, totaling 11,247 gallons (8,283 gallons June 3-11, 1999; 2,964 gallons July 12-15, 1999)
RCRA Corrective Action
State of Georgia Environmental Protection Division
205 Butler Street SE, Suite 1162
Atlanta, GA 30334
Clifton C. Casey, P.E.
Southern Division NAVFAC
Environmental Department (Code 18)
P.O. Box 190010
North Charleston, SC 29419- 9010
- PCE source was 120 feet long by 40 feet wide; 30 to 40 foot horizon below ground surface (bgs); PCE concentrations in landfill source area detected as high as 8,500 æg/L
- TCE, DCE, and VC detected at concentrations of more than 9,000 æg/L in groundwater within the landfill source area
- Because PCE concentrations were as much as 5 percent (%) of the pure solubility phase, the presence of dense non-phase aqueous liquids (DNAPL) was inferred
Leaks from a landfill
Type/Quantity of Media Treated:
- Estimated volume of groundwater treated during the Phase 1was 78,989 gallons ( based on a treatment volume of 1,778 cubic yards and a porosity of 22%)
- Information on volume of groundwater treated during Phase 2 was not provided
Purpose/Significance of Application:
Use of Fenton's Reagent to remediate chlorinated solvents in groundwater
Regulatory Requirements/Cleanup Goals:
- Cleanup goal for the RCRA corrective action at Site 11 was established by the state at 100 æg/L for total chlorinated aliphatic compounds (CACs), defined as the sum of PCE, TCE, cis-1,2 DCE, and VC concentrations in groundwater
- Phase 1 - after first injection, total CAC concentrations were reduced to below the cleanup goal in five of the seven monitoring wells, including one well located within the source area where concentrations had been reduced by >97%. However, total CAC concentrations remained above the cleanup goal in two downgradient monitoring wells; after second injection, total CAC concentration remained at or above the cleanup goal in the two downgradient wells and were found to have increased in other wells. As a result, a second phase of treatment was performed
- Phase 2 - after the first injection, total CAC concentrations were reduced to below the cleanup goal in all but one downgradient monitoring well; however, concentrations increased above the cleanup goal in two downgradient injectors. After the second injection, total CAC concentrations were reduced to below the cleanup goal in the downgradient injectors and remained below the cleanup goal in all wells except for the one downgradient well (total CAC concentration was primarily DCE)
- Sample results from August 1999 showed elevated concentrations of total CACs in one injector located to the east of the area of concern. The Navy has determined that there is a previously unknown source of contamination in this area and is addressing the cleanup of the area separate from the Site 11 area of concern. Data on this cleanup were not available at the time of this report
- Total proposed cost for application of in situ chemical oxidation of Fenton's reagent using the Geo-Cleanse process was approximately $223,000 for Phase 1, including costs for reagents, mobilization, onsite treatment time, injection and monitoring equipment, documentation, and injector construction oversight and materials
- No additional cost data were provided
Naval Submarine Base (NSB) Kings Bay, 16,000 acre facility in Camden County, GA, is the U.S. Atlantic Fleet home port to the next generation of ballistic submarines, and maintains and operates administration and personnel support facilities. Site 11 is the location of a former 25-acre landfill at NSB Kings Bay, known as the Old Camden County landfill, that was operated by the county during the mid-1970s to 1980. A variety of wastes from the local Kings Bay community and the Navy were disposed of in the landfill, including solvents and municipal waste. Site investigations found the groundwater in the area to be contaminated with PCE, as well as TCE, DCE, and VC. On March 18, 1994, NSB Kings Bay entered into a Corrective Action Consent Order with the Georgia Environmental Protection Division to address prior releases of hazardous constituents from Site 11. The Navy selected in situ chemical oxidation using Fenton's reagent for this site based on its successful use by the U.S. Department of Energy (DOE) in remediating chlorinated solvent contaminated groundwater at the Savannah River site. The Navy's approach to the cleanup of Site 11 was to use in situ chemical oxidation to reduce groundwater contaminant concentrations in the source area followed by natural attenuation to address residual contamination.
For the remeditation of Site 11, the Geo-Cleanse process, a patented in situ chemical oxidation technology using Fenton's reagent, was used. The Fenton's reagent consisted of hydrogen peroxide (50%) and an equivalent volume of ferrous iron catalyst that were injected into the subsurface under pressure. The remediation was performed in two phases. For Phase 1, 23 injectors were installed in and around the area of concern and there were two injections of Fenton's reagent into the subsurface, totaling 12,045 gallons. During Phase 2, the system was expanded to add 21 injectors and there were two injections of Fenton's reagent into the subsurface, totaling 11,247 gallons. After two phases of treatment using the Geo-Cleanse process, total CAC concentrations had been reduced to below the cleanup goal of 100 ug/L in all but one well located downgradient of the area of concern. The total CAC concentrations in this well were primarily DCE. The first phase of treatment (two injections) reduced total CAC concentrations to below the cleanup goal in five of the seven monitoring wells, including a reduction of >97% in the well located within the source area. Cost data provided by Geo-Cleanse indicated that the proposed cost for application of in situ chemical oxidation of Fenton's reagent was approximately $223,000 for Phase 1. No additional cost data were available.
In August 1999, elevated concentrations of total CACs concentrations were found in an injector located to the east of the area of concern, indicating the presence of an additional contamination source area in the shallow soil. The soil in this area has been excavated and the Navy is planning to use chemical oxidation to polish the groundwater in this area.