– Minnesotans quoted Theodore Roosevelt, advocated for the blue-spotted salamander and invoked God as they spoke from their hearts to a panel of federal officials Thursday about the economic promise of mining and its threats to the state’s northern forests and lakes.

The evening meeting at the Duluth Entertainment and Convention Center drew about 1,000 people. It marked the start of a two-year environmental impact investigation that will determine whether the federal government will ban copper-nickel mining for two decades in the Superior National Forest near the Boundary Waters Canoe Area Wilderness and Voyageurs National Park.

Blue-hatted mine supporters sat on one side of the auditorium, with sign-bearing lovers of the BWCA on the other. Drawn at random in a lottery, speakers got up one by one. Each spoke for three minutes along lines that have divided the state for a decade.

“Mining is what we do for a living,” said St. Louis County Commissioner Tommy Rukavina. “It’s what we’ve done for 135 years and you people get to come up to the wilderness that we’ve taken care of.”

Those on the other side said copper-nickel mining is not the same as the taconite and iron ore mining that have long been the economic backbone of northern Minnesota.

Waste from the mining of sulfide ore produces an acid that would leach toxic metals and other contaminants into water flowing into the BWCA and the national park. Similar mines have contaminated thousands of miles of streams across the United States, and often require perpetual water treatment to remove contaminants.

“Sulfide mining in that watershed will wreck thousands of outdoor sustainable jobs for short-term benefit,” said Eric Jensen of Backcountry Hunters & Anglers, a national group dedicated to advocating for public lands.

The stakes are high

In December, the federal Bureau of Land Management and the U.S. Forest Service announced a two-year moratorium on mineral exploration on federal lands near the BWCA. That will give the agencies time to conduct an environmental impact review driven by the significant risks to the wilderness and the national park.

If the government decides the risk is too great, that would put the Boundary Waters and Voyageurs on a par with other iconic places across the country, such as the Grand Canyon, Yellowstone National Park and the Front Range in Montana, all of which have been granted similar protections.

The two-year moratorium and the prospect of a two-decade ban have sparked a national landslide of legal and political action, pitting outdoor businesses and environmentalists against labor unions and mining interests. Already, the Forest Service has received more than 30,000 comments — so many that it agreed to extend the comment period from 90 to 120 days and add a second meeting on the Iron Range (not yet scheduled).

Labor and businesses interests, in the meantime, are lobbying the Trump administration to reverse the decision to conduct the mining review, arguing that thousands of jobs and millions of dollars in economic development are at stake.

Though the federal agencies had considered the decision to conduct the review for two years, it was finalized in the waning days of the Obama administration.

Those in favor of the ban are making a jobs argument as well. Some 200 outdoor businesses, from California-based Patagonia to Ely-based Piragis Northwoods Co., have formed a coalition to argue that northern Minnesota’s pristine lakes and forests are an economic engine that deserve protection. Altogether in Minnesota, outdoor recreation generates $11.6 billion in consumer spending and 116,000 jobs, according to data from the national Outdoor Industry Association.

For now, only one company — Twin Metals Minnesota, a subsidiary of Chilean mining giant Antofagasta — is affected by the ban. It was actively exploring federal lands for copper-nickel as it developed a plan for a $2.8 billion underground mine and waste-storage facilities on the Kawishiwi River just outside the BWCA. Last fall, Twin Metals sued the federal agencies, claiming they had no right to deny the company’s renewal of two mineral leases it’s held for decades on federal land.

The state’s politically powerful mining industry argues that the ban would cripple the nascent copper-nickel industry in Minnesota.

“These are the minerals that the good Lord put here so we can extract them,” said St. Louis County Commissioner Pete Stauber. It doesn’t have to be one or the other, mining or clean water, he said: “It’s time we work for a solution for one and the other.”

But retired forester Denny Fitzpatrick of Grand Marais said animals like the blue-spotted salamander are “canaries in the coal mine.” The creatures already are suffering the effects of pollution, and mining might be too much, he said, adding, “Keep them in your analysis.”

A broad impact

The federal review is likely to have a wider impact than just on federal lands. Gov. Mark Dayton has pledged to halt new mineral exploration on state-owned lands near the Boundary Waters and within the Rainy River watershed. Geologists say about two-thirds of the known precious-metal mineral deposits in Minnesota lie within that watershed, and more than half are controlled by the state and federal governments.

But outside the Rainy River watershed, other mining companies are moving ahead. PolyMet Mining Corp., which is one-third owned by the international conglomerate Glencore, is applying for permits to build an open-pit mine near Hoyt Lakes that would drain into the St. Louis River and Lake Superior. Kennecott mining continues to increase its exploration footprint around a copper deposit near Tamarack that would drain into the Mississippi and St. Croix rivers.