Services:

Air Force Center for Environmental Excellence Site Assessment, Remediation & Risk Assessment King Salmon Air Station, Alaska

Issue:

The King Salmon Air Station, located in a sub-arctic region of Alaska, has a long history and more than its share of environmental concerns: drum landfills; groundwater contaminated with free-phase fuel product, chlorinated solvents, and petroleum hydrocarbons; fuel seeps to surface water; impacted wetlands adjacent to anadromous streams; and potential indoor contaminant vapors. Logistics are often complicated since the site is not located on the Alaskan road system - equipment must be mobilized on barges or aircraft to facilitate completion of site assessment or remediation work scopes.

Solution:

OASIS personnel have performed a full array of environmental services for the Air Force at King Salmon for more than a decade - subcontracted through this time period by five different prime contractors at the request of the Air Force, thereby providing institutional knowledge and program consistency. All actions at King Salmon have been performed in accordance with CERCLA under the oversight of the Alaskan Department of Environmental Conservation (ADEC) and U.S. Environmental Protection Agency (EPA)-Region 10. Various contracts have focused on collecting data necessary to update remedial investigation/feasibility studies; design, install and maintain bioventing systems; perform bioventing pilot tests; and complete risk assessments. Treatment methods evaluated and/or implemented at this installation by the OASIS team include reactive iron wall, in-situ biological treatment, bio-slurping, air sparging, bioventing, monitored natural attenuation, diversion walls, phytoremediation, and capping. Data collected during the RI were used for modeling and development of a food web. Sensitive indicator species were identified, and both aquatic upland habitats and species important for subsistence and recreational activities were evaluated. OASIS provided a streamlined and efficient method to perform these risk assessments, using data already collected during other projects at King Salmon. OASIS has also supported the King Salmon community relations program for the last decade.

Results:

A number of sites at the King Salmon Air Force installation have been closed out or relegated to simple monitoring status over the last decade as a result of remedial actions or risk assessments accomplished by the OASIS team. Risk-based cleanup levels (RBCLs) were approved by agencies for several sites. A number of sites required no further action (NFA) on the basis of human health and ecological risk assessment results. Also, several remedial systems were maintained and optimized - for instance, respiration tests and system maintenance were performed on bioventing systems to verify remediation was actually occurring and to determine which sites were clean and ready for closure. In 2005 four bioventing systems were shut down because testing showed that remediation goals had been met. OASIS participated in public outreach meetings by delivering power point presentations regarding feasibility studies and fielded questions, prepared proposed plans and Record of Decisions (RODs), and corresponded directly with members of the community in support of the Air Force.

Case Studies

British Petroleum Exploration (Alaska), Inc.

BPXA's Remediation Management (RM) manages assessment and remediation of contaminated sites...
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U.S. Air Force

The King Salmon Air Station, located in a sub-arctic region of Alaska...
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Alaska Department of Environmental Conservation

Historic petroleum releases at tank farms located in remote Alaska villages can present threats to the environment and local water supplies.
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ADEC

The River Terrace site was a former dry cleaning facility adjacent to the Kenai River in Soldotna, Alaska.
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