Groundwater Containment at Site LF-12, Offutt AFB, Nebraska

Site Name:

Offutt Air Force Base

Location:

Nebraska

Period of
Operation:

Not available;
system was operating in January 1997

Cleanup
Type:

Full-scale cleanup

Vendor:

Information not provided

Technology:
Hydrualic containment consists of three recovery wells. The system operates at an average flow rate of 105 gpm. Groundwater is treated with air stripping and effluent is discharged to a local POTW.

Cleanup Authority:
Installation Restoration Program

Regulartory Point of Contact:
Information not provided
Additional Point of Contact:
U.S. Air Force Air Combat Command

Contaminants:
Volatile Organic Compounds (VOCs)

- Levels of VOCs in soil vapor included 18 ppm acetone, 0.077 ppm toluene, and 0.031 ppm xylene
- Contaminants in groundwater included 500 ppb TCE, 16,000 ppb DCE, 3.3 ppb chloroform, and 7 ppb bromodichloromethane

Waste Source:
Disposal of refuse, waste solvents, and sewage sludge.

Type/Quantity of Media Treated:
Groundwater - Groundwater is encountered between 9 and 18 feet below ground surface.

Purpose/Significance of Application:
Containment of groundwater using active pumping

Regulatory Requirements/Cleanup Goals:
Information not provided

Results:
Limited performance data are available for this application. The volume of contaminant removed as of January 1997 was 12.81 gallons. The average concentration of TCE in the extracted groundwater was 151 ppb.

Cost Factors:
The capital cost for the system was $540,000. The O&M costs average $20,000 per year. Monthly O&M data were not provided.

Description:
Site LF-12 is located at Landfill 4 at Offutt AFB in Nebraska. An estimated 40,000 cubic yards of refuse, waste solvents, and sewage sludge were disposed at Landfill 4, resulting in contamination of soil and groundwater at the site. Low levels of VOCs, including acetone, toluene, and xylene, were detected in the soil vapor. TCE (500 ppb), DCE (16,000 ppb), chloroform (3.3 ppb), and bromodichloromethane (7 ppb) were detected in the groundwater.

A hydraulic containment system was installed at the site, and was operating as of January 1997. Information on the start date for the system was not provided. The system consists of three recovery wells, and operates at an average flow rate of 105 gpm. Groundwater is treated with air stripping and effluent is discharged to a local POTW. Only limited cost and performance data are available for this application. The volume of contaminant removed as of January 1997 was 12.81 gallons. The average concentration of TCE in extracted groundwater was 151 ppb.

The capital cost for the system was $540,000, including design, labor, equipment, materials, and startup. O&M costs average $20,000 per year and include electrical, monitoring, equipment and materials, and operations. No data on actual monthly O&M costs were provided.