Remedial Work at Diggings East Begins
BUTTE, Mont. (September 28, 2026) -- Today, U.S. Environmental Protection Agency (EPA) announced the start of cleanup work at Diggings East, one of the largest remaining corridor projects in the Butte Priority Soils Operable Unit (BPSOU). The project marks major progress in cleanup actions in Butte. The work includes the excavation and disposal of hundreds of thousands of cubic yards of contaminated soils, tailings, and wastes; the construction of lined stormwater basins; and the construction of community amenities such as accessible trails and boardwalks.
The area designated as Diggings East, at Kaw Avenue and George Street, formerly served as an unpermitted municipal landfill, receiving wastes like mine tailings, construction debris, and municipal waste. Approximately 345,000 cubic yards of waste will be removed and disposed of at the Butte Mine Waste Repository (BMWR) during construction. Residents around the project area can expect to see machinery excavating materials and trucks hauling materials away.
“Reaching this major milestone is a meaningful step forward as we work with our partners at every level to serve the community of Butte,” said EPA Region 8 Administrator Cyrus Western. “This construction kickoff is the culmination of years of hard work on design and planning and clearly demonstrates how projects, especially on a massive scale like Diggings East, benefit from collaboration and shared goals of environmental protection.”
“Montana Department of Environmental Quality is excited to see the advancement of this critical work at Diggings East,” said DEQ Director Sonja Nowakowski. “Diggings East is one of the largest remaining cleanup projects in Butte, and the start of construction is a significant milestone for the community. DEQ will continue working closely with our partners to ensure thorough, protective implementation of corridor projects in Butte.”
“Breaking ground at Diggings East marks a major milestone in the ongoing remediation of the Silver Bow Creek corridor. This project will help strengthen the health of the Silver Bow Creek watershed while delivering lasting benefits to the Butte community," said Patricia Gallery, president of Atlantic Richfield Company. "We appreciate the partnership of the EPA, Montana DEQ, and Butte-Silver Bow, and thank the Butte community for their support and the design and construction teams for their dedication to moving this project forward."
“Diggings East is one of the largest remaining corridor projects within the Butte Priority Soils Operable Unit,” said Chief Executive of the City and County of Butte-Silver Bow J.P. Gallagher. “Reaching this stage reflects years of planning, coordination, and partnership among agencies, organizations, and community members. This progress is the result of persistent hard work and collaboration, and it is encouraging to see these long-awaited efforts move forward.”
Preliminary staging work began on August 31. Major hauling of materials to the Butte Mine Waste Repository will begin in the coming weeks. After the construction of stormwater basins, community amenities and vegetation in line with the natural landscape will be installed. The massive project is anticipated to take approximately four years to complete. Eventually, when the project is fully operational, contaminated sediments captured by the system will be periodically removed and disposed of in the BMWR.
Diggings East is one project in a series of remedies to address metals-contaminated stormwater runoff that affects surface water bodies like Silver Bow Creek. Other projects, like Butte Reduction Works and Grove Gulch, are underway or completed. Remedial action at other large project areas, including Northside Tailings and Buffalo Gulch, will begin in the coming years. Under the 2020 consent decree, the settling defendants Atlantic Richfield and Butte-Silver Bow are required to design and implement remedies in the BPSOU corridor under EPA and Montana Department of Environmental Quality oversight.
Since finalization of the 2020 consent decree, settling defendants and the agencies have been working on remedial design for the Diggings East project as well as the other project areas as described in the decree’s statement of work. Designs are carefully reviewed and progressed through different stages until they are finalized. At that point, remedial action can begin.
Other cleanup in the BPSOU, including residential yard sampling and remediation, is also ongoing.
Background
Decades of mining, milling, smelting, and other activities in Butte resulted in large amounts of contamination, wastes, and dumps spread throughout the town. During large storm events, some of this contamination is carried by stormwater downhill, where it then enters into streams and can infiltrate into the groundwater. These separate but interconnected projects in the BPSOU corridor together will help prevent contaminated stormwater and sediments from harming ecosystems and will also reclaim parts of town for community and ecosystem benefit.