Association tackles Colorado county cyanide ban

The Colorado Mining Association (CMA) has launched legal action against a ban on heap-leach cyanide mining in Colorado’s Summit County.

The Denver-based association filed the challenge against the Summit Board of County Commissioners (BOCC) in Summit District Court in late February. The CMA wants the ban declared void.

The commissioners voted for the ban to protect the public from the potential dangers of heap leaching. In fact, the county commissioners received more than 300 e-mails, phone calls and letters supporting a ban.

The CMA says that mines are already regulated by the Mined Land Reclamation Act and the Colorado Water Quality Control Act. It argues that since state and federal laws allow cyanide heap-leach mining, the county, as part of the state, cannot ban the process.

“The Summit Board of County Commissioners exceeded its statutory authority by adopting new performance standards for toxic and acidic chemicals,” says Paul Seby, an attorney representing the CMA.

The Alliance for Responsible Mining said the three mines in Colorado to use open-pit cyanide mining have done so irresponsibly. Most notable was the Summitville mining disaster that resulted in environmental contamination. The U.S. Environmental Protection Agency declared the mine a “Superfund” site or one designated for clean up by the U.S. government because of health and environmental concerns.

Heap leaching extracts precious metals, such as gold, from lower-grade ore. Cyanide or other toxic chemicals percolate through the ore and separate metal from ore more efficiently than other recovery methods. The cyanide-metal solution collects on thick mats below the ore.

Critics say the mats are not effective and that cyanide runoff pollutes watersheds and streams.

The county’s cyanide ban adversely affects the Climax molybdenum mine. Although mothballed, Climax still has an estimated 140 million tons of molybdenum.

The commissioners have a month or so to file a response to the lawsuit.