Gov. Mark Dayton showed a surprisingly fierce environmental side on Tuesday when he defied Republicans by creating a citizens’ board to advise the state on pollution issues, challenged citizens to demand cleaner water from farmers and acknowledged the wrenching decisions he’ll have to make on Minnesota’s first copper-nickel mine.

Dayton’s remarks came at the Minnesota Environmental Partnership’s annual meeting, which usually is closed to reporters. But he asked that his talk to the umbrella lobbying group for the state’s leading environmental organizations be open to reporters, and he used the opportunity to announce the creation of a citizens panel to advise the Minnesota Pollution Control Agency (MPCA), replacing a similar one that the Legislature abolished this year after lobbying from agricultural and other industries.

The new board will not have authority over the agency, as the last one did. But MPCA Commissioner John Linc Stine said that as chairman of the new board, he would consider the board’s views before making final decisions on such key issues as permits, environmental reviews and exemptions to pollution limits.

Dayton signed a bill that eliminated the MPCA’s Citizens’ Board, one element in a broader and contentious environmental bill that dragged the Legislature into a special session last spring. But he expressed misgivings at the time, and said he would work to restore it.

On Tuesday, he said Republicans viewed the legislation as a trophy they could take back to supporters who are “extreme ideologues” and cited it as an example of how they were dismantling government.

“It’s been in place for 50 years,” Dayton said at a news conference after his talk. “They stripped it away and refused to be reasonable about it.”

Rep. Denny McNamara, R-Hastings, who chairs the House Environment and Natural Resources Policy and Finance Committee and was instrumental in the push to end the Citizens’ Board, said he was blindsided by Dayton’s move.

“House Republicans are really proud of the bipartisan work we did with the bill, and the governor signed a couple of months ago, that speeded up the permitting process and removed the Citizens’ Board absolute permitting authority, so we’re kind of surprised by today’s development,” he said.

McNamara speculated that Dayton may be trying to mollify environmental groups, some of which felt burned at the end of the legislative session.

If so, that was not apparent at Tuesday’s meeting. One by one, representatives from the Sierra Club, Transit for Livable Communities and the Land Stewardship Project stood and expressed their thanks for Dayton’s work by giving him cookies. It was in exchange, they said, for the time last spring when he came out and gave them cookies as they rallied outside on the lawn of the governor’s residence.

Dayton also answered questions about critical environmental issues facing Minnesota, providing a rare glimpse into the way he weighs the legacy his generation will leave for its children and grandchildren.

Among them is a proposal by PolyMet Mining Corp. to build a copper-nickel mine in northeastern Minnesota — a plan that, Dayton said, has the potential to tear the state apart even more than the creation of the Boundary Waters Canoe Area Wilderness did decades ago. “This will be the most momentous, difficult and controversial decision I will make as governor,” he said.

The $650 million open-pit mine, which promises to bring some 300 to 350 jobs to the region, would be the state’s first copper-nickel mine and would bring unprecedented environmental challenges.

“The disagreement is what is possible up there to provide jobs, while still preserving the sanctity” of northeastern Minnesota, he said.

Dayton also said he regrets not tackling pressing agricultural water-quality challenges during his first term, but promised it would be a priority for the remainder of his second term. He said the farm buffer-strip bill he proposed and that passed during the session was a major accomplishment, considering that initially it was considered “dead on arrival.”

He said he believes most farmers are responsible, careful stewards of the land. But he pointed to a recent state report that found that more than 90 percent of the lakes and streams in southwestern Minnesota are too polluted by agricultural contamination for swimming, fishing or drinking.

“I refuse to believe we have to accept this kind of contamination because it’s farm country,” he said. “If that makes me an enemy of agriculture, I regret that, but there is too much at stake here,” he said.

Staff writer Patrick Coolican contributed to this story.

Josephine Marcotty • 612-673-7394