An independent consultant will study the potential for mine acid pouring into the Salmon River under a settlement between conservationists and the Thompson Creek mine.
The Boulder-White Clouds Council and Idaho Conservation League on Tuesday announced a settlement in their lawsuit in federal court over acid-generating pyrite. They sued to block the dumping of 186,000 tons of the material into a 500-acre tailings pond.
It requires the Thompson Creek Mining Co., to pay $60,000 for an independent consultant, to be hired by the Forest Service, who will evaluate the long-term options to protect the river. The Forest Service must make all its information on the mine available to the public.
And the agency must select a long-term acid plan for the molybdenum mine, five miles away and 2,000 feet above the river.
“The more public scrutiny and independent review which this mine receives, the better,” said Lynne Stone of the Boulder council.
The Forest Service and the Bureau of Land Management had approved the mine plan to separate pyrite from other tailings material at the processing mill and then use the so-called clean sand to install new drains at the base of the tailings dam.
The pyrite material can create sulfuric acid when mixed with air and water.
Officials at Thompson Creek, which has never violated water-quality regulations in 15 years of operation and has received an environmental award from the Idaho Conservation League, disputed the assertion of acid mine drainage.
They contended there was only a potential for it at the mine, and this month launched a program to improve the drains at the tailings pond.
The settlement allows the summer dumping of acid wastes. In turn, the Forest Service commits to greater public involvement in the mine’s long-term future.
The review will take place in an environmental impact statement, with a draft version issued late this year, the conservationists said.
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