Scientist: Mine needs more study

COEUR d'ALENE — A Colorado scientist is concerned the proposed Rock Creek mine and impacts on the Clark Fork river haven't been explored enough.

"Well, on the Rock Creek mine they took between seven and 10 rock samples and analyzed them," said Ann Maest, a water quality geochemist. "I know there mines in Nevada that have hundreds of samples."

Maest is worried the mine could spread pollutants and unwanted nitrates all the way to Lake Pend Oreille.

"Sediment will still flow toward Idaho," Maest said.

She and other conservationists say water quality predictions prepared by federal land management agencies as part of the permitting process for precious metal mines during the past 25 years were routinely off the mark in concluding the mines would not cause water pollution.

"When we compared the government's predictions with actual water quality reports we found the predictions did not generally agree with reality," said Maest, who co-authored the study released Thursday by the Washington, D.C.-based conservation group Earthworks.

"Over three-quarters of the mines we reviewed in detail had pollution exceedances over water quality standards."

Many of the failures of the water quality predictions in the permit approval studies were due to regulators ignoring previous experiences with hard rock mines, relying on private consultants who have a bias toward satisfying mining clients and failing to take adequate samples to determine overall impacts, Maest said.

"At the proposed Rock Creek Mine in Montana, under a designated wilderness area, they have used only a handful of ore and waste samples from the site to predict the amount of acid drainage," she said. "They need to look at more samples."

Mining industry officials said they were still reviewing the conservation group's analysis, but questioned the inclusion in the study of mines that went bust, were abandoned and may not have been built to agreed-upon environmental protection standards.

"There may be some things in this report that we certainly need to act upon, but it looks to me like a quarter of the mines they decided to look at are abandoned and that may be a little unfair," said Carol Raulston of the National Mining Association in Washington. "There are some mines in their database that are not characteristic of modern mining."

James Kuipers, a Butte, Mont., mining engineer who also authored the conservationists' study, said the findings that water quality protection predictions seldom hold true should prompt regulators to better scrutinize proposals for new mines, including northeast Washington state's Buckhorn gold mine, and the gold and copper Pebble mine in Alaska.

"Mines like the Rosemont copper mine in Arizona and the Atlanta gold mine in Idaho, at least as they are presently being proposed, appear to suffer from many of the same failures as those that were permitted years ago," he said.

Kuipers compared the proposed Atlanta mine to the closed Zortman-Landusky mining complex in northern Montana, where taxpayers must foot the bill for treating contaminated water for decades to come. Atlanta wants to use cyanide to leach gold from the ore left from old mines on a tributary upstream from the Boise River. Environmental groups have warned it could pollute the source of drinking water, irrigation and recreation for the state's most populous river valley.

"The Boise River is more precious than gold," said John Robison of the Idaho Conservation League.

Raulston said the mining industry has launched an acid drainage initiative to find ways to better prevent the discharge of acidic pollutants and heavy metals such as arsenic, cadmium, mercury and lead that are leached out of rock during mining and can be deadly to stream ecosystems. And, modern mines are continually monitoring water quality and adjusting operations to prevent pollution discharge, she said.

"They are required to look at what is happening on the ground and recalibrate those prediction models if the assumptions don't match what they are seeing," she said. "This notion that these prediction models are faith-based initiatives is just not something that really happens in our experience."

— Staff and The Associated Press contributed to this report.