Gov. Mark Dayton may direct the state Health Department to conduct a major review of potential health risks from the proposed copper-nickel mine in northeast Minnesota, the first sign that long-standing concerns from top public health officials about drinking water contamination are now gaining traction.

At a news conference Tuesday, Dayton said that such a review won’t delay the upcoming permitting phase of the controversial mine PolyMet Mining Corp. is proposing to build at an old taconite site near Hoyt Lakes. But if unavoidable adverse impacts to human health are found, “it certainly could” have a bearing on final approval of the $650 million project, Dayton said.

“Credible medical people” have asked for the health assessment, Dayton said, and he will discuss it later this week with health Commissioner Ed Ehlinger.

Ehlinger, the Minnesota Nurses Association, Minnesota Public Health Association, Minnesota Medical Association, and others in public health have urged the state to include a human health assessment as part of the massive environmental impact analysis of the mine. In his public comment issued a year and a half ago, Ehlinger asked the Minnesota Department of Natural Resources to complete a separate review of health risks, and officials from the two state agencies discussed it earlier this year as well.

But in its final version of the 3,000-page environmental impact statement (EIS) completed Nov. 6, the DNR said no. It said it had reviewed the risks, but found no significant potential health impacts. Doing a broader review would delay completion of the final document, and would not “significantly inform the regulatory permits required for the project,” the authors of the EIS said.

A PolyMet spokesman declined to comment, other than to say that the environmental review is completed, and that it concluded there are no public health impacts.

Michael Schommer, a health department spokesman, said that “Commissioner Ehlinger looks forward to discussing the issue with the governor later this week, and to addressing any of his questions about the requests for a health impact assessment.”

PolyMet is the first of several mining companies eager to tap into a major copper-nickel deposit that reaches from the Iron Range up into the Boundary Waters Canoe Area Wilderness. Its NorthMet mine would create an estimated 350 jobs and has brought hopes of an economic rebirth to the Range.

Different risks

But the mine also presents different and greater environmental risks than the taconite industry that has dominated the region for decades. The copper-nickel deposits are contained in sulfide ore, which, when exposed to air and water, produces acid that leaches heavy metals and other contaminants out of the rock and, potentially, into nearby lakes, streams and groundwater.

In his 2014 comments about the proposed mine, Ehlinger listed 21 concerns about whether the environmental review adequately measured the risk to people. He suggested that the DNR demand more detailed environmental information. He questioned whether PolyMet, which provided the data underlying the conclusions, had correctly measured groundwater flow and movement from the mine site. He said that the DNR had used groundwater evaluations for lead, copper, arsenic and other contaminants that were higher than drinking water standards, raising questions about how that might affect the drinking water for the city of Hoyt Lakes and private wells in the area.

He also wanted an inventory of water quality in local wells in order to track whether the mining operations affected them in the future.

A health impact assessment would provide critical information on how to “balance health and citizens’ concerns with economic benefits of the project,” he said in the letter. Such assessments are widely used in environmental reviews, he said, and can include such things as the impact from added traffic and the influx of workers.

The state’s other leading medical organizations echoed those concerns both in public comments made in the EIS and in letters to state agencies.

The Minnesota Public Health Association said in a letter sent to state agencies and the governor that it is concerned the mine could have significant adverse health impacts from air and water pollution, and mercury contamination in fish.

Plea from doctors

Last week the Duluth News Tribune published a plea from a group of northeast Minnesota family physicians asking for a more thorough health review. They said that several independent experts have pointed out flaws and gaps in the EIS data, which was provided by PolyMet and its consultants.

“Once sulfide mining is permitted to move forward, there will be no going back,” it said. “We ask Gov. Mark Dayton and his commissioners to join our call for a thorough, independent and objective assessment of health risks related to the PolyMet sulfide mine project.”