Technology:
In situ Chemical Oxidation Using Fenton's Reagent
- In situ chemical oxidation using Fenton's Reagent involved pressurized injection of concentrated hydrogen peroxide and ferrous iron catalyst to oxidize organic compounds in groundwater
- A two-phase treatment was performed using 23 injectors distributed in two vertical levels; Phase 1 was in the central portion of the plume and Phase 2 was in down-gradient areas
- A pump and treat system had been ongoing at the site since March 1994; as of July 1998, five recovery wells were operating at a combined flow rate of 55 gpm and a UV light system was added to replace a diffused aeration tank for treatment of extracted groundwater; the system was shut off in April 1999
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Cleanup Authority:
RCRA Corrective Action
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Contaminants:
Chlorinated Solvents
- Maximum concentrations - 8,500 ug/L for PCE, 550 ug/L for TCE, and 24 ug/L for cis-1,2-DCE |
Waste Source:
Leaks from a landfill |
Type/Quantity of Media Treated:
Groundwater
- Geology characterized as fine sands interbedded with silty and/or clayey fine sands and some medium sands
- Depth to groundwater is 6 ft, with a flow direction of generally northwest
- An unconfined surficial aquifer is approximately 90 ft thick, and has a hydraulic conductivity of 30 ft/day |
Purpose/Significance of Application:
Use of Fenton's Reagent to remediate chlorinated solvents in groundwater |
Regulatory Requirements/Cleanup Goals:
A cleanup objective for total VOCs in the source area was identified as 100 ug/L |
Results:
- The concentrations of total VOCs were reduced to below cleanup objectives in the central portion and down-gradient areas of the plume after the two phases of treatment
- An additional source of contamination was identified to the north of the treated area; a third phase of treatment using in situ chemical oxidation was planned to address sources of contamination both up- and down-gradient from the previous target areas |
Cost Factors:
- The cost for the first two phases of in situ chemical oxidation and UV oxidation treatment was $1,050,000, consisting of $900,000 for implementation, $65,000 for operations and maintenance, $40,000 for monitoring, and $15,000 for reporting
- Phase 3 was estimated to cost $282,000
- The pump and treat system had an initial capital cost of $1.5 million, with $400,000 expended each year for operations and maintenance ($12 million total projected cost)
- The use of in situ chemical oxidation was projected to save several million dollars compared with the continued use of pump and treat |
Description:
Naval Submarine Base (NSB) Kings Bay is a 16,000 acre facility in Camden County, GA. 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 and DCE. In 1994, a groundwater pump and treat system began operation. This system reduced concentrations of chlorinated solvents, however it was projected that it would require at least 50 years of operation to meet cleanup goals.
The Navy proposed use of in situ chemical oxidation using Fenton's reagent to reduce groundwater contaminant concentrations, followed by natural attenuation to address residual contamination.
The in situ oxidation remediation was performed in two phases, addressing the central portion and down-gradient areas of the plume. The concentrations of total VOCs were reduced to below cleanup objectives in these two areas of the plume. However, an additional source of contamination was identified to the north of the treated area, and a third phase of treatment using in situ chemical oxidation was planned. The cost for the first two phases of treatment was $1,050,000, with Phase 3 estimated to cost $282,000. The use of in situ chemical oxidation was projected to save several million dollars compared with the continued use of pump and treat |
