The Rock Creek Mine’s plan to pump wastewater into the Clark Fork River needs a higher level of scrutiny, the Montana Supreme Court said in a ruling Thursday that voids the mine’s discharge permit.
The proposed silver-copper mine is expected to produce 3.3 million gallons of wastewater daily that likely will be tainted with arsenic, ammonia, nitrates and heavy metals, the ruling said. Revett Minerals, the mine’s operator, planned to treat the water before pumping it into the Clark Fork, which flows into Lake Pend Oreille.
But after mining operations cease in 30 to 35 years, water will keep flowing from the mine. The water might need perpetual treatment to be clean enough to discharge into the river, the Supreme Court said.
Given the uncertainty, the court said Montana’s Department of Environmental Quality made an “arbitrary and capricious” determination that the discharges wouldn’t harm the Clark Fork’s water quality.
The Rock Creek Mine would tunnel three miles to reach a silver-copper deposit under the Cabinet Mountain Wilderness in Western Montana. Once the horizontal tunnel is drilled, water would start flowing out of the rock formation, the ruling said.
“… It is a given that the mine will close in a few years, Revett will be gone and the polluted discharge will continue and cannot be shut off,” Justice John Warner wrote in the majority opinion.
The Clark Fork Coalition of Missoula was one of five environmental groups that challenged the mine’s wastewater discharge permit. “This will require treatment forever,” said Garrett Budds, staff attorney with the coalition. “If the company closes up shop, who do you turn to? The state’s citizens – the taxpayers – get left holding the bag.”
According to court documents, the DEQ would have required a $14 million to $45 million bond for long-term water treatment from Revett Minerals, a Spokane Valley company.
Carson Rife, Revett’s vice president of operations, said the company isn’t abandoning plans for the mine, which would produce an estimated 6 million ounces of silver and 52 million pounds of copper annually. “I would view this as another delay for the project,” Rife said. “It’s unfortunate that we aren’t able to move forward and start employing people up there.”