Abandoned Mine Lands Report

[August 2000] Report to the governor and legislature on the "magnitude and scope" of the abandoned mined lands issue in California.

[2007 Updated Abandoned Mine Statistics]

• Estimates of the number of abandoned mine sites and abandoned mine features in California have been amended since an estimate of 128,800 mining features on 39,000 historic and inactive abandoned mine sites was first reported in the Department of Conservation’s 2000 publication California’s Abandoned Mines: A Report on the Magnitude and Scope of the Issue in the State. These numbers were based on statistical modeling and Geographic Information System (GIS) analyses and are subject to change as the models improve.
  
  

• Based on the above modeling, the Department also estimated in the 2000 Report that 48.5% of the abandoned mine sites were located on federal lands, 1.5% on other public lands, and 50% on private lands.
  
  

• In 2001, the Department completed an effort to scan and digitize all mine symbols on U.S. Geological Survey (USGS) 7.5-minute topographical maps of California, and staff began to field verify the data (see the Topographically Occurring Mine Symbols (TOMS) web page).
  
  

• Based on improvements made to the TOMS database since its release in 2001, the Department of Conservation has recalculated the estimates cited in the California’s Abandoned Mines Report. The new estimates are provided below.
   

  • The estimated number of abandoned mines in the state is 47,084.
    
    Of these, 5,200, or 11%, are estimated to present environmental hazards.
    Also, 39,400, or 84%, are estimated to present physical safety hazards.
     

  • There are approximately 164,795 mining features in the state.
    Approximately 62,000, or 38%, of these features are hazardous openings.
     

  • 67% of the abandoned mine sites in California are on Federal lands.
    31% are on private lands.
    2% are on state and local lands.
    
     

You will need Adobe Acrobat version 4.0 or greater to read this report.

• Overview
• Volume I
• Volume II

Contact Information:

Office of Mine Reclamation
801 K St., MS 09-06
Sacramento, CA 95814-3529
(916) 323-9198

National Association of Abandoned Mine Programs | California Geological Survey | State Mining & Geology Board
Department of Toxic Substances Control | California State Lands Commission
Bureau of Land Management | Mine Safety & Health Administration
Office of Surface Mining |  | U.S. Environmental Protection Agency 
U.S. Forest Service | U.S. Geological Survey