The Bonita Peak Mining District site consists of 48 historic mines or mining-related sources where ongoing releases of metal-laden water and sediments are occurring within the Mineral Creek, Cement Creek and Upper Animas River drainages in San Juan County, Colorado. Historic mining operations have contaminated soil, groundwater and surface water with heavy metals.
Prior to listing as an NPL site, numerous mine reclamation and mine waste cleanup projects were completed in the area by Animas River stakeholders Group, EPA, Sunnyside Gold Corporation, BLM, USFS and the State of Colorado. The occurrence of the Gold King Mine spill in 2015 prompted neighboring downstream communities to place pressure on the Town of Silverton and San Juan County to list the site on the National Priorities List, and address these ongoing issues of draining mines and the impacts of legacy mining. The Bonita Peak Mining District site was added to the National Priorities List in September 2016 after lengthy negotiations with the Town of Silverton and San Juan County.