Counterpoint: What you need to know about PolyMet and groundwater flows

A lead story in the Star Tribune on Sept. 1 suggested that water from PolyMet's mine could impact the Boundary Waters Canoe Area Wilderness (BWCA). A letter submitted to regulators late in the environmental review process by John Coleman, a wildlife ecologist who works for the Great Lakes Indian Fish and Wildlife Commission, asserts that groundwater could flow north from the PolyMet site to the Peter Mitchell taconite mine and eventually into the Boundary Waters some 20 miles away. This is simply not the case.

The reality is, existing field data from monitoring wells and surrounding lake elevations strongly support the conclusion that project groundwater will not move through the bedrock toward the Boundary Waters. All water quality and quantity data, as well as modeling analyses in the environmental-impact statement used to determine the impacts of the NorthMet project, are appropriate and adequate.

As part of the environmental review process, the co-lead agencies (the Minnesota Department of Natural Resources, the U.S. Army Corps of Engineers and the U.S. Forest Service) and their independent environmental engineering consultant have considered Coleman's allegations. A June 22 technical memo from the agencies concludes: "[T]he lack of hydrologic response at the proposed NorthMet project mine site supports a conceptual model whereby water from the proposed NorthMet pits would not flow into the Northshore pits." It continues: "[A]dditional modeling of flowpaths … would not be beneficial."

In a letter dated Aug. 5, the Environmental Protection Agency (EPA) submitted its comments on the preliminary final environmental-impact statement to the co-lead agencies. The EPA specifically addressed the "potential post-closure northward flow path in bedrock groundwater" and concluded that "the proposed strategy [is] an appropriate response."

This is exactly how the environmenta-review process is supposed to work.

In an e-mail to the agencies, Coleman admits that he is not "a groundwater modeling professional" and that "any analysis should be redone by professionals in the field of groundwater modeling." Coleman changed inputs to the environmental-impact statement model to show that groundwater could flow north. Of course, changing any inputs would affect the outputs. But those new outputs do not reflect reality.

The same assumptions that predict a north flow path would also predict that the Partridge River would be dry during much of the year. Additionally, the model would predict that current dewatering of the Peter Mitchell pit would already have caused a drawdown of water levels in wells that PolyMet already has in place, which is not the case. The changes that Coleman made to the model do not accurately portray actual conditions.

Even though it is unlikely that groundwater would ever flow north toward the BWCA, PolyMet has already proposed to implement proactive measures to ensure that water does not flow north. New monitoring wells will be installed before operations begin, which would allow for more than 10 years' worth of additional data collection prior to any potential for a northerly flow to occur. If the actual data suggest that northerly flow could occur, mitigation measures would include maintaining the water in the NorthMet mine pit at a lower elevation, ensuring that the water stays within the St. Louis River watershed.

So what's next for the environmental-review process? Coleman's issues will be addressed in the final environmental-impact statement coming out later this fall. PolyMet is committed to developing Minnesota's first copper-nickel mine the right way. A way that is safe and protective of the environment and accomplished by our employees who live there, work there and raise their families there. This is PolyMet's commitment to the state of Minnesota and the community where we will mine. We are doing this right.