One Minnesota, the campaign theme of Gov.-elect Tim Walz, will be tested early and often, especially on three nagging environmental issues that have long defied middle-ground agreement.

Whether to open Minnesota’s first copper-nickel mine in the Arrowhead is the most highly charged environmental issue since wilderness designation of the Boundary Waters Canoe Area in the 1970s. That one fractured Walz’s DFL Party so deeply that some wounds won’t mend to this day.

Another rupture exists over whether an oil pipeline should be trenched near some of the state’s most popular recreational lakes and wild rice marshes prized by indigenous people.

And still another conflict, over nitrogen runoff from farm fields, has come to define Minnesota’s rural-urban divide as much as any dispute.

For the first time in 30 years, Minnesota will have a governor with rural bona fides in Walz, a Mankato educator who has represented the largely-rural First District in Congress for a dozen years. A “Main Street” populist with a welcoming personality, Walz is driven to be a bipartisan healer.

But, oh boy, it will be a steep climb out of the rocky chasm opened between Minnesotans by eco-issues. Along the way there lurks more prickly buckthorn than Showy Lady’s Slippers.

An early task will be appointing leaders to the Minnesota Pollution Control Agency and the departments of Natural Resources and Agriculture who can ignore walls of bureaucratic silos and become a team. While Minnesota has a deep bench of highly regarded professionals with sparkling résumés, this time the state needs folks with walrus-thick skin, patient and welcoming personalities like Walz’s and a genuine, focused desire to drive issues to “yes.”

Walz would do well to put the copper-nickel issue behind him early. The DNR recently issued permits to Toronto-based PolyMet to mine near Hoyt Lakes, after a decade of environmental review. There are serious issues here: Mining these metals has a dreadful eco-history, and exhausted mines have been abandoned with taxpayers stuck with cleanup.

But after a painstaking review, the DNR is satisfied that the myriad concerns have been dealt with, and it’s time to accept reality that this project will proceed. Labor (the “L” in DFL, after all) wants it for the economy-goosing jobs the region needs, and a squadron of powerful GOP and DFL legislators strongly support it.

Walz could better turn attention to the next proposed mine, being explored by Twin Metals, that poses a serious danger to the famous Boundary Waters Canoe Area Wilderness.

The Enbridge Line 3 pipeline recently received a “certificate of need” from the Minnesota Public Utilities Commission, and it, too, seems inevitable. There are legitimate concerns over routing, which snakes through prized northern lake and wild rice country. There are also real concerns that the line would carry crude oil from Alberta tar sands whose mines release staggering amounts of greenhouse carbon.

It might be best to involve Lt. Gov.-elect Peggy Flanagan to push routing Line 3 farther north along the corridor of the aging line it will replace. Flanagan, a member of the White Earth Nation with environmentalist support, would be especially welcomed by indigenous people opposed to the project.

Perhaps the most intractable issue is nitrogen runoff from farmland that’s responsible for killing and damaging our namesake lakes, for sending oxygen-depleting chemicals to the Gulf of Mexico and north to Lake Winnipeg, and for contaminating broad quantities of groundwater and rendering well water unsafe for drinking.

Walz knows this one and has suggested two good initial steps: increasing cover crops to soak up the stuff and planting vegetative buffers along drainage ditches and small streams. Big ag needs to get behind serious efforts to resolve a large problem they have created. Walz can talk farm talk, and for once in decades farmers should listen.

The list of additional eco-challenges is long, including runoff and stench from animal feedlots, further reducing greenhouse gases from coal-burning power plants and, of course, those walleyes and Lake Mille Lacs. That list will surely dog the new governor for as long as he’s in office, in important part because decisionmaking is shrouded in an ad hoc process that encourages political mischief outside public view. This inevitably breeds suspicion that will crimp the governor’s drive for “One Minnesota” solutions.

Walz would do well to get behind the re-creation of the policy-setting citizens board that well-served the Pollution Control Agency since it was created in 1967. The board was sent packing in 2015 in an ill-advised, late-session deal by legislators seeking more political influence over the PCA outside public view.

The citizens board was an open forum that built public confidence in consensus decisionmaking.

And while he’s at it, Walz could back legislation for a citizens board to govern the Department of Natural Resources.

One Minnesota is a worthy goal that simply cannot succeed behind closed doors.

Ron Way, of Edina, is a former official with the Minnesota Pollution Control Agency and the U.S. Department of the Interior.