Abandoned Mine Lands Program - Arizona
Bureau of Land Management (BLM) Arizona manages and conserves 12.1 million acres of public land and 17.5 million subsurface acres within Arizona. The lands managed by the BLM are consistent with the principle of “multiple use” which may include cattle grazing, wild horses, recreation, wildlife habitat, and mining. Widespread mining, both on- and off-site beneficiation, and smelting have occurred in Arizona's mining districts since the 1860s. Many of the lands originally mined were patented. However, abandoned mine sites commonly occur on public land near all of the historic mining districts. Many industrial mineral sites also occur in Arizona, but these are typically small and pose little risk to people or natural resources.
Significant mining areas in Arizona are:
- southeastern and eastern Arizona: Porphyry and vein deposits (copper, silver, molybdenum, gold, tungsten, lead, zinc)
- central Arizona: Vein and massive sulfide deposits (copper, led, silver, gold, manganese, tungsten, mercury)
- west-central Arizona: Vein deposits (gold, silver, copper, lead, zinc, manganese, uranium, tungsten)
- southwestern Arizona: Placer and vein deposits (gold, silver, manganese)
- northern Arizona: Breccia pipes and stratabound deposits (uranium, vanadium, manganese, copper)
The estimate for Arizona is over 200,000 abandoned mine features with an estimated 20,000 being located within the National System of Public Lands (NSPL). Currently the BLM has documented about 10,000 features in the Abandoned Mine and Site Cleanup Module (AMSCM) database. We continue to identify as many as 750 features each year through active inventory by our partners. Most sites are physical safety sites that require temporary fencing, backfilling or bat-friendly enclosures. Environmental remediation actions include the construction of repositories, in-place capping, and groundwater treatment systems. There are minimal features that directly impact watersheds, but do impact adjacent arroyos during rain events. Most impacted areas do not support fisheries, but do impact recreational and urban interface areas. The largest impact is the physical safety threat to recreational users.