Department of
Environmental Quality

On August 12, 2009, the EPA Office of Inspector General (OIG) accepted EPA Region 10's action plan for the East Mission Flats Repository. The OIG stated that the "planned corrective actions address the remainder of our concerns." The plan is to do enhanced monitoring at the repository to address technical uncertainties identified by the OIG, such as improving the understanding of the site’s vertical ground water gradients. The OIG did not require any changes to the repository design.

In response to public input, the repository height has been reduced from 62 feet to 34 feet. East Mission Flats will not be easily visible from the Old Mission. Only soils contaminated with mine waste will be accepted at the repository. Municipal wastes and residential garbage will not be accepted.

Now that OIG’s concerns are resolved, Region 10 and DEQ will continue preparation work at East Mission Flats. Starting August 20, DEQ will begin building the base pad for the decontamination facility near the entrance. The pad will be built with about 14,000 cubic yards of contaminated soils from residential area cleanups. This equals about 1,800 truck loads of yard soil waste. Once the material is placed, the soils will be stabilized to protect them from erosion should a flood occur next winter or spring.

The decontamination facility will be similar to the one now in use at the Big Creek repository. The base for the decontamination facility must be built this year to make sure the repository is up and running for the 2010 season. The base must settle for a few months before the concrete structures are built on top. This will ensure that the concrete won’t crack or warp.

EPA has received a number of inquiries about the Bunker Hill Superfund site and, specifically, the East Mission Flats repository. Some have asked for the Administrator to review the Region’s decision-making, some have asked for a moratorium at East Mission Flats, and some have expressed support for moving forward with East Mission Flats construction. Mathy Stanislaus, Assistant Administrator for EPA’s Office of Solid Waste and Emergency Response (OSWER), visited the Bunker Hill site to meet with stakeholders and see the cleanup, including East Mission Flats. As part of his review, the Assistant Administrator may reconsider the work being performed at East Mission Flats. This could include stopping development of the repository. As this review is completed, one of his main considerations will be to ensure that EPA is fulfilling its mandate to protect public health and the environment. This includes an assessment of the implications of delaying development of the East Mission Flats repository. A decision is expected soon.

DEQ, EPA, and UMG also are exploring possible locations for a long-term ICP repository in the Box. This may include further expansion to the west to cover the contaminated wetland soils. This long-term ICP repository would take in mining-contaminated materials from both the populated and non-populated areas of the Box.

Current efforts are focusing on determining the rate at which ICP material will likely be generated in future years throughout the Box. This rate will determine how big the long-term ICP repository would need to be. When the long-term ICP repository is to be created, the agencies will carry out a public involvement process.