Region 8
Superfund Program
National Information
Regional Information
Site Information
National Priorities List (NPL) History
Proposed Date
10/26/1989
Final Date
8/30/1990
Construction Completion Date
9/10/1999
Ellsworth Air Force Base
Click for an interactive map |
Site Type: Federal Facility Final NPL City: Ellsworth AFB County: Meade, Pennington Street Address: Ellsworth AFB ZIP Code: 57706 EPA ID: SD2571924644 Site ID: 0800585 SSID: 08K1 Site Aliases: None Congressional District: At Large |
Site Description
Ellsworth Air Force Base (EAFB) is a U.S. Air Force Air Combat Command base six miles east of Rapid City, South Dakota, next to the town of Box Elder. EAFB covers about 4,858 acres in Meade and Pennington counties. The base includes runways, airfield operations, industrial areas, housing and recreational facilities. EAFB is surrounded by farming and ranching lands, rural housing and light commercial activities.
EAFB began in July 1942 as the Rapid City Army Air Base, a training facility for B-17 bomber crews. In 1948, as part of the 28th Strategic Reconnaissance Wing, it became a permanent facility.
Historically, EAFB has been operations headquarters for a variety of aircraft, as well as the Titan I Intercontinental Ballistic Missile system and the Minuteman missile system. Presently, the 28th Bombardment Wing (B-1B bombers) is the host unit of EAFB.
A half century of military activities left contamination on the base and on private land beyond its boundaries. EPA added EAFB to its National Priorities List (NPL) on August 30, 1990. The Air Force, EPA, and the state of South Dakota have worked as partners to clean up EAFB.
Site Risk
Studies to identify hazardous substances were conducted in 12 general areas of EAFB, including landfills, a fire protection training area, spill sites, industrial areas, and an explosive-ordnance disposal area. The hazardous substances found most often on the base are solvents and jet fuels, located in both soils and groundwater.
Some groundwater contaminants have moved beyond the EAFB boundary to the east and to the south at low concentrations, but above federal drinking-water standards. Continued use of the contaminated groundwater over long periods for household purposes, particularly as drinking water, could pose unacceptable health risks.
| Media Affected | Contaminants | Source of Contamination |
| soil, sediment, surface water, groundwater | solvents, jet fuels | military activities |
Cleanup Progress
Construction Complete
The Air Force installed cleanup systems to address possible future health risks. Construction of cleanup systems is complete at all contaminated areas. The cleanup includes groundwater pump-and-treat systems, bio-dechlorination, landfill covers, soil treatment systems, excavation activities and natural attenuation (lessening). The systems are functioning properly.
EAFB obtains its potable water from the Rapid City Municipal Distribution System. In past years, EAFB obtained its water supplies from five wells that had been installed into deep bedrock aquifers at the base. These wells were taken out of service and have been abandoned in accordance with South Dakota requirements. Shallow groundwater in the area is used for domestic water supplies and for livestock watering.
Groundwater contamination has impacted the drinking water wells of some homes to the east and south of the base. In 1999, EAFB completed a water supply line to provide treated water from the Rapid City municipal water system to off-base residents. Water was supplied to off-base residents by EAFB until 2007, when a license for operation and maintenance of the water supply line by the city of Box Elder became active.
The Air Force capped landfills and has enforced institutional controls to prevent unauthorized access to those landfills and to prevent the caps from being disturbed.
Contaminated groundwater is pumped out of the ground and purified to drinking water standards. The treated water is then either discharged to a local drainage, to the EAFB wastewater treatment plant or re-injected into the aquifer. A contaminated groundwater plume extends off-site to the east. However, the plume has been stopped at the site boundary and a gap in the plume is now evident. Natural attenuation of the remaining contamination will continue to be monitored.
These groundwater cleanup systems will be in operation for 20 to 30 years to complete the cleanup. However, treatability studies are being implemented to enhance and possibly replace current pump-and-treat technologies. The relatively low levels of contamination in off-base areas are expected to lessen within the same time frame.
Cleanup of the entire EAFB, including 20 years of groundwater treatment, is expected to cost approximately $30 million. All cleanup activities are being performed by the Air Force. EPA and the state of South Dakota provide regulatory oversight.
Five-Year Review
The third five-year review of the remedial actions implemented at EAFB has been completed by the Air Force, as required by Section 121 of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, also known as Superfund). The review was conducted from March 2010 through September 2010.
The five-year review determined that groundwater remedies at EAFB are in place and operating, and that they protect human health and the environment because contaminated groundwater is contained at the base boundary, high concentration source areas have been identified and are being treated, and because land use controls and alternate water supplies prevent groundwater use.
All existing remedial systems require monitoring and occasional minor modifications. The EAFB environmental flight staff continue to conduct these efforts and ensure that the remedies remain protective of human health and the environment.
Community Involvement
In June 2010, 16 individuals were interviewed and asked for their impressions of how the environmental cleanup work at Ellsworth AFB is progressing. Each was asked a series of questions that were developed in May 2010 by the Ellsworth AFB RPM group. The interviewees comprise a cross-section of the local community and include four county or municipal employees or elected officials, two local businessmen or developers, two on-base residents, and eight off-base residents.
Overall, interviewees said they were aware of the cleanup, and seemed satisfied with the progress being made. Eleven people said the effort is going well, and five had no comment or no impression.
Site Documents
You will need Adobe Reader to view some of the files on this page. See EPA's PDF page to learn more.
Note: Best way to open a very large file: right-click and save it to a folder.
Annual Update to the Five-Year Review, August 2011 (PDF, 1 pg, 43K)
Third Five-Year Review Report, September 2010 (PDF, 308 pp, 4.5MB)
Contacts
EPA
Patricia Smith
Remedial Project Manager
U.S. Environmental Protection Agency, Region 8
1595 Wynkoop Street (8EPR-F)
Denver, CO 80202-1129
303-312-6504
800-227-8917 ext. 312-6665 (toll free Region 8 only)
smith.patricia@epa.gov
John Dalton
Community Involvement Coordinator
U.S. Environmental Protection Agency, Region 8
1595 Wynkoop Street (8OC)
Denver, CO 80202-1129
303-312-6633 or
800-227-8917 ext. 312-6633 (toll free Region 8 only)
dalton.john@epa.gov
DENR
Joane Lineburg
South Dakota Department of Environment & Natural Resources
Joe Foss Building
523 East Capitol
Pierre, SD 57501-3181
605-773-3296
joane.lineburg@state.sd.us
USAF
Jerry Styles
Remedial Project Manager
U.S. Air Force
28CES/CEANR
2125 Scott Drive
Ellsworth AFB, SD 57706-4711
605-385-2677
jerald.styles@ellsworth.af.mil
View Documents at:
The Administrative Record
28CES/CEANR
2125 Scott Drive
Ellsworth AFB, SD 57706-4711
605-385-2677
South Dakota Air & Space Museum
2890 Davis Drive, Building 5208
Ellsworth AFB, SD 57706
605-385-5188
Links
Ellsworth Air Force Base Site at the South Dakota Department of Environment & Natural Resources
