Two copper-nickel mines proposed for the Boundary Waters area are the subject of a raging tug-of-war between mining and environmental interests.
Conservationists oppose the PolyMet and Twin Metals projects because this type of mining invariably produces sulfuric acid that could devastate Minnesota’s water. Mining interests argue that with modern technology, it is possible for responsible companies to operate pollution-free copper-nickel mines.
A key example they use is the Flambeau Mine, located on the Flambeau River near Ladysmith, Wisconsin. This mine produced copper, gold, and silver for four years in the 1990s. Since its closure, it's become the site of 10 acres of wetlands, and miles of public hiking and horseback riding trails.
In a 2013 letter addressed to Gov. Mark Dayton, Mining Minnesota asked the governor to follow Wisconsin's lead, citing Flambeau as proof that “copper, nickel and other much-needed metal production can has been done safely and successfully, without polluting local waters.
“Right next door in Wisconsin, the Flambeau Mine is an excellent example of a copper mine that operated for several years, and now has been closed and reclaimed for more than 10 years in full compliance with Wisconsin laws.”
The mine’s parent company, London-based Rio Tinto, wrote in a news release in 2013, "Testing shows conclusively that ground water qulity surrounding the site is as good as it was before mining."
But the Flambeau Mine's own data shows otherwise, according to Dr. Robert Moran, a hydrologist and geologist whose resume includes consulting work for nonprofits, mining companies, and government agencies worldwide.
In light of a Wisconsin state senator's recent proposal to revoke mining-related environmental standards, the Sierra Club hired Moran to review decades' worth of historical reports that the Flambeau mine submitted to the Wisconsin Department of Natural Resources.
He saw that far from being pollution-free, concentrations of toxic elements such as zinc, arsenic, and sulfate in the surrounding groundwater greatly exceed pre-mining levels, as well as standards of survival for many aquatic lifeforms.
But what the Flambeau mine didn't report could have far greater consequences, Moran says.
Typically, mines will specify whether their water testing samples were filtered for comparison with drinking standards, or unfiltered for comparison with wildlife and recreation standards. Naturally, the level of toxins in filtered water would be much lower than that of unfiltered water, but the Flambeau reports were largely ambigous about which were used, Moran says.
"Part of the problem is a lot of this data just isn't there," he says. "There's decades of information, and it's still ambiguous. As far as we can tell, these are filtered samples. But the fish and other organisms, they don't drink filtered water."
Flambeau would also pick and choose which tests to include in their routine reports, Moran says. Arsenic, uranium, and other "controversial" metals are largely left out of water quality updates. The methodology of Flambeau's reports to the public were flawed to begin with, so it's nearly impossible to tell through a historical review just how bad the situation really is, Moran says.
"In short, the Flambeau Mine is the poster child for a severely flawed permitting and oversight process."