Butte Priority Soils
Butte is a city that grew directly within and around mining activity. Homes, schools, and neighborhoods were built among mine shafts, waste rock dumps, and processing areas long before the health risks of metals like lead and arsenic were fully understood. The Butte Priority Soils cleanup focused on protecting people — especially children — where they live.
Why residential soils were a concern
Historic mining left metals such as lead and arsenic in soils around homes and yards.
These metals can pose a health risk when soil is tracked indoors, dust accumulates in attics, or children play in bare soil.
Because exposure can occur in everyday settings, residential areas were prioritized early in the Superfund process.
What "Priority Soils" means
"Priority Soils" refers to residential areas where contamination levels warranted action, people lived full-time, and exposure pathways were most direct.
These areas were addressed before many other parts of the site because protecting residents was the highest priority.
How cleanup was done
Cleanup in residential areas focused on reducing exposure rather than changing the entire landscape.
Typical actions included removing contaminated surface soils, replacing soils with clean material, installing protective vegetation, and removing and replacing attic insulation when needed.
Work was performed yard by yard, often while people continued living in their homes.
The Residential Metals Abatement Program (RMAP)
RMAP was created to test residential soils and attic dust, perform cleanup where needed, and provide these services at no cost to residents.
The program has operated for decades and remains an important part of protecting health in Butte.
The scale of the work
Cleanup under the Butte Priority Soils Operable Unit involved thousands of properties, extensive sampling and analysis, coordination with homeowners, and long-term follow-up.
This was one of the largest residential soil cleanup efforts in the country.
Much of this work has now been completed.
What protections remain today
Even after major cleanup work is complete, monitoring continues, re-testing is available if conditions change, and maintenance of clean soil and vegetation is encouraged.
If you disturb soil during construction, plan major landscaping, or have questions about your property, help is available.
Stormwater and urban runoff
Rain and snowmelt can carry metals from urban areas into Silver Bow Creek.
To address this, stormwater ponds are being constructed, runoff is treated before entering waterways, and new green spaces are being created.
This work builds on residential cleanup to protect downstream areas.
Why this work matters
The Butte Priority Soils cleanup represents a core promise of Superfund: protect people where they live.
It reflects decades of effort to reduce exposure, support families, and create safer neighborhoods — while respecting the city's history and character.