EPA Research Partner Support Story: Passive remediation alternative
Partner: Idaho Department of Fish and Game (IDFG), Washington State Department of Ecology
Challenge: Development of a passive remediation alternative at the Bunker Hill Superfund Site (Lane Marsh)
Resource: Technical Investigation
Project Period: 2015 – Present
The Lower Coeur d’Alene River Basin in northern Idaho and eastern Washington is an active habitat for migratory birds (including the Canadian Tundra Swan) and part of the Bunker Hill Superfund Site, a former lead refining and smelting facility. Historical and ongoing transport of contaminated sediment to floodplains, marshes and side lakes from the Bunker Hill site has resulted in annual acute lead toxicity of migratory birds that utilize the surrounding wetlands for feeding during migration. The concentration of lead in some sediments is so elevated that acute effects of lead toxicity are seen within as little as a two-week period. The loss of bird life has also resulted in reduced use of the river basin for recreational activities. The historical release of contaminated materials has led to the contamination of more than 18,000 acres of prime water fowl habitat. The size and scope of the sediment contamination prohibits the use and application of traditional remediation practices at this site, including sediment removal. A passive treatment option that reduces the potential for biological uptake of lead is required. EPA ORD is collaborating with state partners to develop a passive soil amendment option that would reduce bioaccessible lead concentrations in wildlife.
“The Washington State Department of Ecology appreciates ORD’s involvement in the Bunker Hill Superfund Site. The tools being developed by ORD will not only ensure that lakes and marshes receive appropriate cleanups and reduce contaminant transport into Washington, but also may assist us in determining the best remedial strategies at our own cleanup sites.” – Washington State Department of Ecology, Toxics Cleanup Program Hydrogeologist Sandra Treccani
“Abundant natural resources and clean functioning ecosystems are highly valued by local and regional residents and a huge part of why we choose to live here. The IDFG is committed to restoring healthy and productive ecosystems in the lower basin. We are happy to have been able to support and partner with EPA ORD in the effort to find new, innovative, and cost-effective approaches to the wildland contamination problems we face there.” – IDFG Regional Wildlife Habitat Biologist David Leptich
EPA ORD in collaboration with Region 10 (Pacific Northwest) have conducted an initial site investigation to evaluate geochemical cycles, contaminant distribution and chemical speciation of lead throughout Lane Marsh. This information was used to develop laboratory conditions for bench scale studies evaluating the performance of sediment amendments to reduce lead bioavailability. Research is ongoing as scientists begin selecting specific materials for field trials.
ORD’s partners will use the results of the bench scale testing and field trials to determine the best options for passive remediation efforts. In addition, the potential for remedy selection based upon existing geochemical properties and contaminant speciation will be employed at other locations within the Lower Coeur d’Alene Basin. Successful identification and deployment of affordable and effective passive sediment remediation technologies will ultimately result in a reduction of bioavailable lead improving the ecosystem by protecting migratory birds and subsequently revitalizing recreational activities in the Lower Basin.
More information can be found on the Bunker Hill Superfund Site profile.