The BLM Abandoned Mine Lands (AML) Program supports the overall BLM mission of public land and water conservation. The AML program addresses physical safety and environmental hazards associated with abandoned hardrock mines on public lands administered by the BLM.
Over the last 150 years depleted mining operations were abandoned or moved to other locations, leaving scarred and contaminated land across many parts of the West. In many cases these activities were not properly reclaimed. The BLM must address physical safety and environmental threats associated with abandoned mines.
BLM California has approximately 520 abandoned mines on public lands that have potential impacts on water quality in seventeen priority watersheds. Impacts include elemental and methyl mercury point and non-point discharge, acidic mine drainage from mine openings and dumps, asbestos mines discharge, and airborne erosion of mine wastes. All of these impacts are regarded as posing a serious public health risk. In addition California has over 120 high-risk mine openings.
Bureau of Land Management California Abandoned Mine Lands Program Web Page
State of California - Department of Conservation Office of Mine Reclamation - Abandoned Mine Lands Unit