Image # 3104
Mining Leachate at Abandoned Mine Near Ouray, Colorado
Seeking silver, lead, and later gold, hardrock miners founded many of Colorado's historic mountain communities. But while many of these high-altitude settlements have been long abandoned, the mines continue to affect water quality downstream. The Upper Colorado River Basin, which includes Ouray County, is a NAWQA site. Water samples taken from stream channels near mining sites have concentrations of copper, arsenic, zinc and lead in excess of the Canadian standards of safety for aquatic biota, (no US standards currently exist) and some streams, such as this one, are unable to support any aquatic life. In January 2001, the Bureau of Land Management adopted new rules which, for the first time, attempted to set environmental performance standards for hardrock mining. The rules also required mining companies to post bonds to help insure restoration of mining sites and allowed the BLM to deny mining permits if companies failed to meet these standards. President George W. Bush suspended these regulations on March 23. The BLM has since decided to retain the financial bonding requirements (with a time extension granted to mining companies) but has not yet issued a decision on the other proposed rule changes. According to the EPA's 2001 Toxic Release Inventory, the hardrock miing industry ranks first in the production of toxic waste. Clean-up costs are estimated to run between $32 billion to $72 billion dollars.