Soil Vapor Extraction:
- Eight vertical vapor extraction wells and one horizontal air injection well
- 32 soil probe clusters
- Vapor-liquid separator; vapor-phase carbon vessel
- One positive displacement vacuum blower for extraction wells
- Range of total system flow rates - 268 to 499 cfm, with an average of 409 cfm; range of flow rates at the well heads - 22 to 132 cfm.
- Well head vacuums ranged from 3.9 inches to 7.0 inches Hg, with an average of 5.8 inches Hg.
- ROD signed: September 24, 1993
|EPA Remedial Project Manager:|
U.S. EPA Region 4
61 Forsyth Street
Atlanta, GA 30303-3415
Phone: (404) 562-8538
|Naval Facilities Engineering Command |
Remedial Project Manager:
Katherine H. Landman
MCB Camp LeJeune
Atlantic Division, Code 1823
1510 Gilbert Street
Norfolk, VA 23511-2699
Regulatory Requirements/Cleanup Goals:
- The ROD identified the following cleanup goals for soil: TCE - 32.2 µg/kg, PCE - 10.5 µg/kg, benzene - 5.4 µg/kg.
- No air emission standards were specified for this application, however the State of North Carolina required the facility to provide documentation about potential air emissions for this application and to include carbon treatment for air emissions.
- Results of confirmation soil boring samples showed TCE and benzene at nondetectable levels in all soil boring samples. PCE was reported at levels below the cleanup goal of 10.5 µg/kg in all but one sample.
- According to LANTDIV, EPA approved shutdown of the system because the single exception was slightly above the soil remedial goals and the contaminated groundwater under the area of concern was being addressed by a pump-and-treat system.
- For the discharge stack, concentrations ranged as follows: TCE - ND to 2.2 µg/L; PCE - ND to 147.4 µg/L; benzene - ND to 10.2 µg/L; and ethylbenzene - ND to 7.4 µg/L.
- Total cost of $469,949 was expended for remedial activities at Area A including $222,455 for capital costs and $247,485 for operation and maintenance (O&M) costs.
- The total cost of $469,940 corresponds to a unit cost of $27 per cubic yard (yd3) for 17,500 yd3 of soil treated.
Camp LeJeune Military Reservation (also known as Marine Corps Base Camp LeJeune), established in 1941, is a 170-square-mile installation near Jacksonville, North Carolina, that provides housing, training, logistical, and administrative support for Fleet Marine Force Units. Site 82 is was used for waste disposal and, in 1994, drums and debris were removed from the site. Area A was a portion of Site 82 at which residual soil and groundwater contamination remained after removal of drums and debris. Soil at Area A was contaminated with volatile organic compounds (VOC), primarily TCE, PCE, and benzene. The ROD specified SVE for remediation of contaminated soil.
The SVE system used at Area A included eight vertical vapor extraction wells (installed to a depth of 15 to 16 feet bgs), one horizontal air injection well (horizontal displacement of 330 feet; total depth of 15 feet bgs), 32 soil probe clusters (for measurement of subsurface vapors; each cluster consisted of one shallow and one deep probe at approximately 6 feet and 12 feet bgs, respectively), a vapor phase separator, a vapor-phase carbon vessel (granular activated carbon), and a vacuum extraction unit (VEU) that included a positive displacement blower that was used to apply vacuum to the extraction wells. The results of confirmation sampling showed that TCE and benzene met the cleanup goals in all soil boring samples. For 23 of 24 soil boring samples, PCE was reported at levels below the cleanup goal of 10.5 µg/kg. For one soil boring sample, PCE was reported at 29 µg/kg compared to the cleanup goal of 10.5 µg/kg. According to LANTDIV, EPA approved shutdown of the system because the single exception was slightly above the soil remedial goals and the contaminated groundwater under the area of concern was being addressed by a pump-and-treat system.
According to the Naval Facilities Engineering Command Remedial Project Manager, the SVE system at Area A was cost-effective. Significant other work was being performed at the site, including the construction and operation of a 500-gallon-per-minute (gpm) pump-and-treat plant to treat groundwater contaminated with VOCs, and helped to keep costs down because overhead and operations costs were shared. In addition, an on-site laboratory was being used for other analytical work on the base, and the shared cost of the use of that facility also helped to keep the cost of the SVE application low.