Doi

I. Background

Asarco owns and operates the Ray Mine complex in Gila and Pinal Counties, Arizona. The complex includes a 265,000 ton-per-day open pit copper mine, a copper smelter with an acid plant, solution extraction/electrowinning plants, mills, concentrators, leaching systems, and related support facilities. Ore from the mine is transported eighteen miles to the Hayden Smelter for processing. In 1996, the complex produced 430 million pounds of copper anodes, over 70 million pounds of copper cathodes, 1.3 million ounces of silver in concentrate, and 623,000 tons of sulfuric acid. The Ray Mine is the second most productive copper mine in Arizona and the third most productive copper mine in the United States. CENTER FOR BIOLOGICAL DIVERSITY v. USDOI 13275 In 1994, Asarco proposed a land exchange with the BLM in order to consolidate its holdings and to support and expand its mining operations at the complex. As amended in 1997, the proposed land exchange would convey to Asarco in fee simple thirty-one parcels of public land totaling 10,976 acres (the “selected lands”). In return, Asarco would convey to the BLM eighteen parcels of private land totaling roughly 7,300 acres…