Abandoned Mineral Lands

Abandoned mineral lands (AML) are among the many types of disturbed lands in the National Park System. AML sites are 1) underground and surface mines, 2) placer and dredge sites, 3) oil, gas, and geothermal wells, and 4) associated facilities. Commodities mined at these sites range from "hard rock" minerals, mainly those that contain metals such as gold, silver, lead, and copper, to "soft rock" minerals such as coal, salt, and sand/gravel. Sites often have waste rock piles (unprocessed, sub-grade mined rock), tailings (mined rock that has been processed to remove the desired commodities), abandoned roads, fuel storage tanks, drainage diversions, buildings such as mills and assay shops, deteriorating structures such as headframes and tramways, and abandoned heavy equipment.

Not surprisingly, the legacy of abandoned mineral lands spans North America. Mining for flint, obsidian, and native copper for tools and weapons, turquoise for jewelry, and clay for pipes began with the arrival of prehistoric peoples. During the 16th century, expectation of mineral wealth drove Coronado's conquistadors beyond the edge of civilization to the heart of an unknown continent. Later, the lure of gold and the prospect of great wealth were responsible for Europeans settling in the western United States. With the beginning of the industrial age, the young nation, hungry for energy, exploited its mineral resources of coal, oil, gas, and uranium, and this too left its mark on the land. Deserted, these sites stand in silent testimony to those who pioneered this country in search of mineral wealth.