OVERVIEW

Andy Davis

Geomega, Boulder, Colorado

Cynthia Moomaw

Geomega, Boulder, Colorado

George Fennemore

Geomega, Boulder, Colorado

Randy Buffington

Placer Dome, Bald Mountain Mine
Elko, Nevada

Approximately 2670 million metric tons of metal ore (e.g., copper, gold, iron, zinc) was handled at surface and underground mines in the United States in 1998, with surface mines accounting for 98 percent of the total (USGS, 2000a). Production in the metal industry accounted for 9790 million dollars in 1998, which was 0.1 percent of the gross domestic product (USGS, 2000b). The United States is second only to Africa as the world's largest producer of gold and second to Chile as the world's largest producer of copper (USGS, 2000b). Gold production in 1999 was dominated by mines located in Nevada and California, with a combined production accounting for nearly 80 percent of the U.S. total. The value of mine production in 1999 was approximately $3.1 billion.

Mining and mineral recovery generates many wastes. Mining overburden (material removed to gain access to the ore body) is excluded by EPA as a waste because it is not considered a discarded material within the scope of the Resource Conservation and Recovery Act (RCRA), and is thus exempt from Subtitle C [261.4(b)(3)]. Mining wastes fall into three categories, including extraction, beneficiation, and mineral processing. Extraction, beneficiation, and 20 specific mineral processing wastes are exempt from RCRA Subtitle C regulation [261.4(b)(7)] according to the Bevill Amendment. Other mineral processing wastes are regulated as hazardous waste if they exhibit one...