Less than four-tenths of a mile. That's how close the new location eyed by a Chilean copper mining conglomerate for a future ore-processing facility is to northern Minnesota's Birch Lake, whose waters flow north into the state's beloved Boundary Waters Canoe Area Wilderness.

The proposed Twin Metals copper-nickel mine is years, maybe even a decade, away from completing state and federal environmental reviews, and there are no guarantees it will successfully navigate those hurdles.

But as the project comes into focus, as it did recently with the new information about the facility's alarming move closer to Birch Lake's shore, it is Minnesotans' duty to track developments and understand the risks and economic benefits inherent in the venture. That is especially true in an election year.

The state's next governor and its incoming legislators will be in office when Antofagasta-owned Twin Metals submits its formal proposal — expected in the next 18 months — kicking off an arduous review and permitting process. With U.S. Environmental Protection Agency Administrator Scott Pruitt's scandals casting a pall over his agency, the state's scientific review takes on even greater importance.

Minnesota needs leaders who grasp the significance and who will ensure that the resources are in place at state agencies to conduct a rigorous, technology-driven and independent analysis. That includes appointing agency heads who not only have expertise in this critical subject area but the backbone to stand up to special interests wielding political pressure either for or against the project.

As the 2018 campaign ramps up, the new information from Twin Metals is a reminder of how high the stakes are. Unlike PolyMet, another proposed copper mine in northern Minnesota, Twin Metals is located within the Boundary Waters watershed (though not within the BWCA itself, as sometimes is mistakenly believed). Still, within the watershed is a big concern because acid runoff is a historic risk from mines like this.

In May, Twin Metals publicly updated the location for the ore-processing facility. This is where mined rock is milled and put through a "flotation" process that uses water and other chemicals to separate out copper and other metals. The site, which had been planned for a location 1.36 miles to the west of Birch Lake, is now planned near the underground mine just to the lake's east.

The new location, which would encompass 100 acres, is 0.38 miles from Birch Lake's eastern shore. The BWCA is another 5.5 miles to the northeast.

Twin Metals officials contend that the new location will make the operation more efficient, and they say being closer to the lake is a nonissue because the project will have to go through the same regulatory hurdles to ensure that mining can be done responsibly in this location. But the ore-processing facility's proximity to the shoreline does matter, and it defies common sense to suggest it doesn't add risk.

Even rigorous review and permitting provide no guarantee against accidents. The new location shortens pollutants' pathway to the water and may make it more difficult for interventions to work. At risk is the nation's "most heavily used wilderness area,'' attracting 250,000 visitors annually who enjoy its canoe routes, expansive forest and hiking trails.

The facility is also a massive change for Birch Lake, a popular area for fishing and other recreation. Mining operation photos on the website for Michigan's well-run Eagle Mine give a sense of how disruptive the facility will be. Keep in mind the Twin Metals facility is projected to process 10 times the volume of ore each day that Eagle does. The $1.2 billion mine project is expected to create 650 jobs, according to company estimates, as well as 1,300 spinoff jobs in the region.

Those seeking the state's highest offices have to do more than they've done in the past: reflexively tout the jobs this new industry will bring or provide vague assurances about environmental protections. Candidates instead should prove that they are committed to a state review process that is fair, expert and thorough. And that they will stand by it even if the conclusion is this: Mining cannot be done responsibly in this location.