EIELSON AIR FORCE BASE ALASKA EPA ID# AK1570028646
EPA Region 10 Fairbanks North Star Borough Fairbanks
1st Congressional District Other Names:
Last Update: September, 2007
Site Description Threats and Contaminants
Media Affected:Groundwater & Soil
Groundwater contains lead and volatile organic compounds (VOCs) such as benzene, xylene, and toluene. Several areas of subsurface petroleum-contaminated soil and floating petroleum product are the sources of continuing groundwater contamination. Ingesting or coming into direct contact with contaminated groundwater or soil may pose a potential health threat. Polychlorinated biphenyl (PCB)-contaminated fish were found in a slough that runs through the base.
The site is being addressed in five long-term actions focusing on cleanup of two fuel contaminated areas, trichloroethylene spills, drum burial area, landfills, and a comprehensive evaluation of the entire site.
Fuel Contaminated Areas: In 1991, the Air Force began investigating the nature and extent of fuel contamination at the site. In late 1994, EPA and the Air Force selected bioventing and soil vapor extraction (SVE) as the remedy to treat the fuel-contaminated source areas. Construction activities were completed by the Air Force in early 1997.
TCE Spill Areas: In 1992, the Air Force began an investigation of the TCE spill areas at the site to determine the type and extent of contamination. In 1995, SVE was the remedy selected to clean up the areas. A pilot scale SVE implemented in 1996, indicated that only minimal amounts of contamination remained. Therefore, a full scale SVE was not installed, and instead, institutional controls and monitoring were implemented in 1997.
Drum Burial Areas: In 1992, the Air Force began an investigation into the nature and extent of contamination at the drum burial areas. In 1995, EPA selected a remedy that includes capping one drum burial area and bioventing/SVE for a historic on-site gas station. These remedies were subsequently amended, based on additional data. Soil removals at the gas station largely removed the soil contamination. Lead contamination in the groundwater is immobile and a Technical Impracticability waiver was used to waive the action level for lead. Institutional controls and monitoring were implemented in 1995. Capping of the drum burial site was subsequently determined to be unnecessary because the area did not pose an unacceptable risk for plausible future land uses.
Landfill Areas: In 1992, the Air Force began an investigation into the nature and extent of contamination at the landfill areas on the site. In 1995, EPA selected a remedy that includes capping the site's largest historic landfill to prevent direct exposure to landfill waste. Groundwater adjacent to the landfill does not exceed regulatory levels. The Air Force completed construction in 1997.
Entire Site: In 1991, the Air Force began an investigation to evaluate any comprehensive risks due to the nature and extent of contamination at the entire site. This investigation evaluated any cumulative human health and environmental risks remaining at the site after remedies for individual areas have been selected. In September 1996, EPA selected a remedy which included the removal of PCB-contaminated sediments and soils above ten parts per million (ppm) at Garrison Slough. Materials with contamination levels up to 50 ppm were disposed of in an existing on-site CERCLA landfill. Materials with contamination levels greater than 50 ppm were treated or disposed of in accordance with the Toxic Substance Control Act. The Air Force completed construction in 1998.
The Air Force, in conjunction with EPA and the Alaska Department of Environmental Conservation, continues to monitor ongoing cleanup actions and environmental conditions under an annual site-wide monitoring program.