On July 16, 2012, the Washington State Department of Ecology issued water quality violations along with monetary penalties to Crown Resources Corporation, a fully owned subsidiary of Kinross Gold, for numerous water quality violations at the Buckhorn Mine in Okanogan County. A string of violations occurred in the spring and summer of 2011, and some are ongoing. The violations involve failure to adequately capture and treat contaminants emanating from the mine, including: discharge from a surface pile of Potentially Acid Generating (PAG) rock into surface water; a large slope failure; and unpermitted discharge of mine water into surface water. The assessed penalty is $395,000.
“The Buckhorn Mine has water quality problems, and water quality standards should be strictly enforced,” states David Kliegman, Director of OHA. “We hope that the issuance of these long overdue violations will help motivate Crown/Kinross to prioritize control of contaminants from the mine.”
According to an Ecology news release, Lorraine Powell, the Ecology hydrogeologist responsible for overseeing the mine permitting, said, “Crown Resources is required to establish and maintain a groundwater capture zone at all times to protect water quality outside the capture zone. Water has to be pumped out of the mine workings and surrounding capture zone areas and treated onsite so water quality is protected while mine operations continue.” The Ecology press release states, “Water management during spring snow melt has been a well-documented problem at the mine.”
Failure of the capture zone around the mine means that instead of Crown/Kinross having control over the water impacted by mining, contaminated water is escaping into the environment. This lack of control has been ongoing since shortly after the mine began operating in 2008. In April 2009, Crown was fined $40,000 for inadequate capture of mine contaminants. Additional dewatering wells were drilled to try to control the unregulated discharges, but elevated mine-related contaminants have continued to adversely affect ground water on the east side of the mine and surface water to the west -- all located outside the capture zone.
In spring 2011, the discharged treated mine water, combined with spring snow melt, caused a steep slope below the treatment facility to give way, uprooting trees and releasing a landslide of mud that scoured Gold Bowl Creek for about half a mile. Water quality testing of Gold Bowl Creek clearly showed that contaminants from waste rock leachate were entering the creek, and the effects were evident for months.