Along with over 2,000 other people, I was an interested observer at last week’s metro meeting on comments involving the Supplemental Draft Environmental Impact Statement (SDEIS) for Polymet’s proposed copper-nickel mine in northeastern Minnesota. Besides the comments made by citizens, Polymet, the Minnesota DNR, and federal agencies had experts there to answer all kind of questions posed to them.
The proposed mine site and the treatment plant to treat wastewater from mining activities are bordered on either side by the Partridge and Embarrass rivers. New information has come up that shows the flow rate of the Partridge river is greatly underestimated in the water model contained in the SDEIS.
This is vitally important because it becomes very hard to estimate how much contaminated water from waste rock leaching and groundwater movement may be released from the mine site. Without having accurate numbers to judge the flow rate of the Partridge river, it becomes merely guesswork to judge the longterm cost of financial assurance to clean up mine pollution.
Both the Partridge and Embarrass rivers drain into the St. Louis river watershed, which flows into Lake Superior. The St. Louis river watershed already is contaminated with sulfates, which play a role in converting mercury into a form accumulating in fish tissue. And Polymet’s early testing shows that mercury that leaches from mining waste rock is four times more than the state’s water quality standard.
Then there is the issue of climate change and our extreme weather patterns. Just two years ago, the St. Louis river experienced a “once in a lifetime” flood that caused upwards of $60 million dollars in damages, with losses to Jay Cooke State Park, the community of Fond du Lac, and western Duluth.
In my last post, I wrote about the St. Louis being an “area of concern” within the Great Lakes for pollution, and how the state and federal governments are committed to spending large amounts of public money to remove the area as a pollution hotspot by 2025. There may be a great risk to spending all these public dollars when a mine upstream may suffer from a tremendous flood that can bring significant contamination down the river.
When we don’t know the amount of contaminated water to be removed from Polymet’s mining site, and we haven’t accounted for more likely severe weather events bringing a higher degree of contamination to the St. Louis river watershed, it becomes apparent that the SDEIS needs more work and better data before any mining permits are ever issued.