Mining company drops cyanide plan

NAMPA, Idaho – A California mining company that received a permit to use cyanide in the Boise River watershed has changed its plan and will use an alternative method to leach gold from ore.

The mine, scheduled to open next year, would be the first new gold mine to open in at least 20 years in the Boise River watershed, which provides drinking water to 200,000 people. Desert Mineral Mining of Laguna Beach, Calif., wants to process ore cast off by past miners on Three Point Mountain, 20 miles southeast of Boise on Blacks Creek Road.

The mining company received a permit in April from the Idaho Department of Environmental Quality to use cyanide, a poisonous chemical, to leach the gold from the rock.

During the approval process, neighboring ranchers and environmental activists sent letters, called Gov. Dirk Kempthorne and filled a hearing to protest the mine because of concerns over using the chemical.

But the company said recently that it will use sodium bromide to extract the gold instead.

Mine owners say sodium bromide has few long-term effects on the environment.

The company will also remediate past mining damage, said Dan Terzo, Desert Mineral’s chief operating officer.

“Our sister company’s past testing proves that we can restore heavy-metal contaminated waste piles to a safe organic state,” Terzo said.

The change of plans pleased John Robison of the Idaho Conservation League.

“The fact they found an alternative to cyanide is good news,” Robison said.

“We certainly appreciate Mr. Terzo being flexible to technology with less impact on the environment.”

The new process is more costly than cyanide leaching, but because it is not using cyanide, the mine will not require a tailings pond.

Terzo will have to return to the Idaho Department of Lands with a new reclamation plan before continuing.

Terzo earlier planned to mine 120,000 tons of ore but reduced that goal when he applied for the cyanide permit.

He hopes to build a pilot plant at the mine site to test methods of cleaning up pollution left by other mining operations.