The Berkeley Pit

The Berkeley Pit is a large, abandoned open-pit copper mine in Butte, Montana, filled with toxic groundwater that has been heavily contaminated by minerals and chemicals from mining activities. Over the years, rainwater and groundwater have seeped in, creating a dangerous lake with extremely acidic water containing high levels of metals like arsenic and copper. It is considered an environmental hazard due to potential seepage into nearby water supplies and its impact on local ecosystems. Efforts are ongoing to manage and remediate the site, but it remains a notable example of industrial environmental legacy.