News Releases from Region 08

EPA releases proposed plan to complete Butte, Montana Superfund site cleanup

Proposal advances the final cleanup of the Butte Priority Soils operable unit in Butte, Montana

Helena, Mont. (April 11, 2019) -- The U.S. Environmental Protection Agency (EPA) today released a proposed plan to complete final cleanup actions at the Butte Priority Soils Operable Unit (BPSOU) of the Silver Bow Creek/Butte Area Superfund site in Butte-Silver Bow County, Montana. The proposed plan was developed by EPA in consultation with the Montana Department of Environmental Quality (DEQ) and is based on recent evaluations of what is needed to complete the BPSOU remedy. This announcement coincides with the start of a 60-day public comment period in which EPA will solicit public comments on the proposed plan. The comment period starts April 11, 2019 and goes through June 11, 2019.

“EPA remains committed to securing a final cleanup plan for the Butte Area Superfund site that will deliver results and bring closure to the community,” said EPA Acting Regional Administrator Deb Thomas. “This proposal reflects the collective progress we have made toward a detailed plan to address remaining soil, waste and water quality concerns. We look forward to receiving feedback from the Butte community as we work to finalize a plan by the end of the summer.”

While responsible parties (Atlantic Richfield Company, Burlington Northern Santa Fe Railway Company, Union Pacific Railroad Company and Butte Silver Bow County) at the Silver Bow Creek/Butte Area Superfund site have completed much of the actions specified in a 2006 Superfund Record of Decision, work remains to complete the cleanup and protect human health and the environment. Last year, EPA set a goal of completing final actions and beginning the deletion process for the site by 2024. To meet that goal, EPA and DEQ have been in discussions to define remaining actions and determine how they will be implemented.

EPA’s proposed plan proposes to amend the 2006 Record of Decision (ROD) for the cleanup of the site and details a path forward on several concerns to the community, including the resolution of additional investigation and cleanup actions related to soils, waste removal, and surface and ground water quality. All these actions comprise the final elements of the surface water portion of the BPSOU remedy.

The 2006 BPSOU ROD established in-stream water quality standards for the BPSOU remedy. Based on extensive data collection and modeling, EPA has determined that some of these standards are technically impracticable to achieve. To facilitate moving forward on final cleanup actions, the agency is proposing to amend current in-stream acute water quality standards for copper and zinc (which apply during storms and other high-flow events) and replace those standards with EPA promulgated water quality criteria. Other changes include defining expanded areas for floodplain removal, expanded groundwater controls, removal of the Diggings East and Northside Tailings and the construction of stormwater retention/detention basins in those areas, and the construction of other stormwater control basins and fixtures. The proposed plan also seeks public comment on removing existing contingency requirements for construction of a physical stormwater treatment plant, in-stream flow augmentation and infiltration barriers from the BPSOU remedy.

EPA will conduct two public meetings to describe the proposed plan and solicit comments before a Record of Decision Amendment is released later this year. EPA will carefully consider all public comment, and the final Record of Decision Amendment may vary from EPA’s proposed plan based on public input.

All actions required under the amended ROD will be implemented through a Consent Decree entered in federal district court or through other enforcement mechanisms provided to EPA in the Superfund law.

The two public meetings will be held on April 23, 2019, and May 23, 2019, at the Montana Tech Campus Library Auditorium, 1300 West Park St., in Butte from 6:00-8:30 p.m.

The proposed plan, associated documents, and information on how to submit comments can be found at www.epa.gov/superfund/silver-bow-butte.