MADISON, Wis. — Gov. Scott Walker voted to ban copper and gold mining in Wisconsin two decades ago. Now he may be asked to lift the one of-a-kind prohibition as his fellow Republicans push to continue opening up the state’s north woods to mining.

Conservationists have warned pollution from mining for so-called sulfide ores such as copper, zinc and gold could devastate northern Wisconsin’s water — one of the reasons the Legislature adopted a de facto moratorium on such mines in 1998. But after relaxing the state’s iron mining laws four years ago, GOP lawmakers have introduced a bill that would lift the prohibition. They say they want to jump-start the economy in the rural, sparsely populated northern half of the state.

The measure could put Walker in a tough situation, forced to choose between sticking with his long-ago vote when he was in the Assembly or signing the bill in hopes of sparking a slumbering industry. Supporting the measure would be a reversal he might have to explain on the campaign trail next year.

“Support for repeal (of the moratorium) would be a complete contradiction and a clear indication that the governor is not concerned about people and wildlife being exposed to toxic pollutants,” said Sarah Barry, a lobbyist for environmental advocacy group Clean Wisconsin.

So far, Walker hasn’t said what he’ll do.

Mining gold, copper, zinc, nickel and other metals isn’t as simple as sifting rocks through a pan. The metals are often bonded to sulfur, forming sulfide compounds. Such compounds produce sulfuric acid when exposed to oxygen and water, creating the risk that mining runoff could pollute streams and rivers.

In Utah in 2008, the U.S. Department of the Interior, Fish and Wildlife Service sued the Kennecott Utah Copper Corporation, alleging its copper and gold mine near Salt Lake City released selenium, copper, arsenic, lead, zinc and cadmium that injured migratory birds, wetlands and aquatic habitats. The company ultimately reached a consent decree to give land to The Nature Conservancy to preserve as wetlands.

And in British Columbia, Canada, officials in 2014 imposed a drinking water ban and closed a salmon fishery after a dam on a wastewater pond at a gold-and-copper mine failed, sending millions of cubic meters of water and silt spilling into lakes and rivers.

At least 11 states are currently home to active sulfide mines.

Wisconsin lawmakers passed a bill in 1998 that requires sulfide mining applicants to prove that a sulfide mine has operated somewhere in North America for 10 years and that a mine has been closed for 10 years without causing pollution. Conservationists refer to the statutes as the “Prove It First” law. Critics consider it a moratorium on sulfide mining. So far no companies have come forward to offer examples of operations that fit the standards.

No other state has a similar restriction, although Minnesota lawmakers are considering an identical one. No sulfide mines are currently operating in Minnesota, but two companies are considering sites in the state’s Arrowhead region north of Lake Superior.

Wisconsin Republicans have been pushing to re-start mining since 2011, when Walker was elected governor and the GOP took full control of the Legislature. In 2013, Walker signed Republican state Sen. Tom Tiffany’s bill to dramatically relax state iron mining regulations. The bill was designed to help Gogebic Taconite develop an open-pit iron mine near Lake Superior. With strong opposition from American Indian tribes and environmentalists, the company ultimately gave up on the project after deciding wetlands around the potential site made the project unfeasible.

Now Tiffany is working to open the door for sulfide mining. His proposal would eliminate the moratorium, allowing large-scale sampling without environmental impact statements. It also would prevent administrative law judges from blocking DNR mining application decisions. Administrative law judges handle disputes involving government regulations at a level below a trial court; the bill would force mine challengers to go to circuit court.

Ronald Kuehn, a lobbyist for the American Exploration and Mining Association and mining company Aquila Resources Inc. Aquila, is seeking permits to mine zinc and gold in Michigan’s Upper Peninsula and is considering two potential sites in northern Wisconsin’s Taylor and Marathon counties. He said the moratorium is handcuffing mining companies. Since there’s no guarantee the DNR would agree with an applicant that a mine hasn’t polluted, no one wants to invest in exploring Wisconsin deposits, he said.

“What you see is a total inability to even apply for a license to mine,” Kuehn said.

Tiffany, whose district borders the Upper Peninsula, echoed the same arguments he made for the iron mining bill four years ago, saying mining could help a region where unemployment generally is worse than the statewide average.

A Flambeau Mining Company operation near Ladysmith that ran for four years before closing in 1997 proves sulfide mining can be done safely, he said. Flambeau employed about 70 people and brought millions in tax dollars to city, county and state government.

“Tourism is wonderful, but it’s the icing on the cake,” Tiffany said. “It’s not a bread-and-butter industry. Something like mining can be that.”

The bill has yet to get a committee vote, but opposition is mobilizing. Half a dozen environmental groups and three American Indian tribes have formed a coalition opposing the measure. They contend the Ladysmith mine is still polluting 20 years later, pointing to elevated levels of copper and zinc in a stream that runs near the site.

“(Walker’s moratorium vote) helped ensure mining could only proceed if it proved the industry’s claims,” said Dave Blouin, mining chair for Wisconsin’s Sierra Club chapter. “A vote for Sen. Tiffany’s mining giveaway bill would put his stamp on our Legislature’s race to the bottom of environmental standards.”


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