The Cleanup, by Area
The Butte–Silver Bow Superfund site is vast. Cleanup work does not happen everywhere at once, or in the same way.
To manage this complexity, the site is divided into specific geographic areas. Each area focuses on a particular set of environmental challenges — such as mine flooding, residential soils, stream contamination, or tailings ponds.
These areas are known as Operable Units, but you can think of them simply as places where different kinds of work are happening.
How to use this page
You do not need to understand every area to understand the cleanup.
- Click an area that is familiar to you
- Start with where you live or recreate
- Or explore out of curiosity
Each area page explains what happened there, what cleanup work has been done, what is ongoing, and what comes next.
You can always return here to see how the pieces connect.
Butte Mine Flooding
More than 10,000 miles of underground mine workings beneath Butte, along with the Berkeley Pit, filled with groundwater after mining stopped. This area focuses on managing contaminated water to prevent uncontrolled release and protect surrounding waterways.
Ongoing water management and treatment
Explore Butte Mine FloodingButte Priority Soils
Residential neighborhoods in Butte were affected by contamination from historic mining. Cleanup focuses on protecting residents by removing and replacing contaminated soils and attic insulation.
Largely completed; monitoring ongoing
Explore Butte Priority SoilsStormwater and Urban Runoff
Rain and snowmelt can carry metals from urban areas into Silver Bow Creek. New stormwater ponds are being constructed to capture and treat runoff while also creating public green space.
Construction ongoing
Stormwater cleanup and future amenitiesStreamside Tailings (Silver Bow Creek)
For decades, Silver Bow Creek carried mine tailings and contaminated sediments downstream. Cleanup has involved removing contaminated material, rebuilding the creek channel, and restoring floodplains.
Major cleanup completed; monitoring ongoing
Explore Streamside TailingsWarm Springs Ponds
The Warm Springs Ponds were constructed to capture tailings before they entered the Clark Fork River. They now serve as both a key part of cleanup strategy and an important wildlife and recreation area.
Long-term remediation planning
Explore Warm Springs PondsWest Side Soils
This area includes waste rock dumps and contaminated groundwater outside urban Butte. Investigations are underway to understand risks and determine long-term cleanup approaches.
Investigation ongoing
Explore West Side SoilsBlacktail Creek Investigation
Blacktail Creek flows through mining-impacted areas west of Butte. Investigations are evaluating conditions in soil, surface water, and groundwater as part of the West Side Soils work.
Investigation ongoing
Explore Blacktail CreekHow these areas connect
Although each area is managed separately, they are environmentally connected.
Water flows downhill. Sediments move during floods. Groundwater travels through rock and soil.
That's why cleanup decisions are made carefully, with attention to how actions in one area affect others.
If you're curious about the broader picture: