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Settlement to Clean Up Contaminated Tailings and Develop 120 Acres of Connected Greenway in Butte, Montana

A September 16, 2020 settlement between the U.S. Environmental Protection Agency (EPA) and the Atlantic Richfield Company will result in approximately $150 million in new cleanup work to address contaminated tailings and treat contaminated stormwater and groundwater at the Silver Bow Creek/Butte Area Superfund site in Butte, Montana. Additionally, the consent decree sets aside 120-acres for connected greenways in Butte – natural park spaces with reconstructed wetlands, flowing water, abundant native plants, wildlife habitat, play areas, and interpretive features. Nearly eight miles of trails and boardwalks will allow all-season access to these areas.

“This is tremendous news and allows for an expanded cleanup in Butte and Walkerville that will benefit the community in the coming decades.  We look forward to continuing to work with the community to implement this consent decree which will create recreational opportunities and scenic greenway at the site and provide protections for human health and the environment.” EPA Regional Administrator (Region 8) Gregory Sopkin

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Information about Atlantic Richfield Company

The Atlantic Richfield Company, primarily owned by British Petroleum, and operating worldwide, currently produces, refines, and markets oil and gas, and conducts exploration of fossil fuels. As a result of a merger with the Anaconda Company (also known as the Anaconda Copper Mining Company) in 1977, Atlantic Richfield is the successor-in interest to, and assumed the liabilities incurred by the Anaconda Company and/or its subsidiaries and related corporations or businesses, and predecessors, which were owners and operators of "facilities" within and adjacent to the Butte Site and the Anaconda Smelter facility. 

Information about the Silver Bow Creek/Butte Area Superfund Site

The Silver Bow Creek/Butte Area Superfund site, in and around Butte, Montana, includes 26 miles of stream and streamside habitat downstream from Butte. Since the late 1800s, mining wastes have been dumped into areas in and around Butte, as well as into streams and wetlands near mining operations.  Additionally, smelters and mills produced aerial emissions contaminated with arsenic and heavy metals. These activities contaminated soil, groundwater and surface water with heavy metals.

The Butte Priority Soils Operable Unit (BPSOU) cleanup will: remove contaminated tailings at the Northside and Diggings East Tailings areas and along Silver Bow and Blacktail Creeks; treat more contaminated stormwater and groundwater to keep that water out of the creeks; and cap and revegetate additional mine waste areas on Butte Hill. The amended Record of Decision also expands the successful Residential Metals Abatement Program to more homes in Butte and Silver Bow County.

More information about the site is available from the Agency’s Silver Bow Creek/Butte Area Superfund site profile webpage.

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Overview of the Consent Decree

The BPSOU consent decree and supporting documents approved by the Federal District Court of Montana addresses many cleanup actions to be accomplished over the next several years in Butte and Walkerville, Montana. The consent decree requires Atlantic Richfield to undertake or finance over $150 million in cleanup actions, provide financial assurance for future cleanup actions, and provide enhanced community benefits through the implementation of end land use plans along the Silver Bow Creek Corridor.

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Contact Information

For more information contact

Nikia Greene
Remedial Project Manager
U.S. Environmental Protection Agency
Region 8
10 West 15th Street Suite 3200
Helena, MT 59626
(406) 457-5019

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