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Iron Range sulfide mining can be done without harming wild rice or raising mercury levels

Minnesotans should work together with the mining industry to create a win-win scenario for the entire state.

I support environmental activism. As a nation, we’ve made great strides thanks to the efforts of environmentalists.

Harlan Christensen

“Minnesota and mining: Our children, our waters and wild rice are political pawns,” published April 15 by Ely resident C.A. Arneson, paints a frightening picture of political intrigue and dangers to our children and communities. With this masterpiece of environmental fear-mongering, Arneson reveals a disturbing problem with the environmental lobby in Minnesota.

Increasingly radical environmentalism, with its “all or nothing” approach, seems bent on destroying rather than working with the mining industry industry.

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By using selective scientific data, Arneson’s commentary implied to Minnesotans that our children are in danger as a result of the political intervention of Iron Range legislators. But those legislators did the right thing.

Please allow me to fill in some blanks. I will not argue Arneson’s contention of sulfide effects on wild rice and methyl mercury. What I will argue, however, are some key omissions.

Important MPCA evidence and other scientific studies offer evidence that rice beds and waters containing elevated levels of iron significantly reduce mercury methylation and make sulfide nontoxic to wild-rice seedlings. Iron makes the difference, and we are talking about the Iron Range, right?

Iron can render sulfide nontoxic

The March 2014 MPCA Wild Rice Sulfate Standard Study Preliminary Analysis revealed that iron presence in mud at levels greater than 1 milligram per liter causes sulfide to bond with the iron and renders it nontoxic to wild rice. Field testing revealed a whopping 8.0 to 84.6 mg/L of iron present in waters throughout the proposed future copper/nickel/PGM mining area in northeastern Minnesota.

Source: MPCA
Iron presence in mud at levels greater than 1 milligram per liter causes
sulfide to bond with the iron and renders it nontoxic to wild rice.

The MPCA report contains an entire section on iron’s ability to make sulfide nontoxic to wild rice, and considers it important enough to include an illustration formatted for publication. I’ve yet to hear it mentioned by an environmental group.

After acknowledging that some people may not care about wild rice, Arneson moves on to describe how sulfite can lead to methyl mercury and damaging effects to developing embryos, but fails to disclose widely accepted scientific evidence that iron reduces mercury methylation.

“Reduction of Net Mercury Methylation by Iron … Implications for Engineered Wetlands,” published in Vol. 37, No.13, 2003 Environmental Science & Technology by University of California, Berkeley researchers, provides extremely detailed evidence that mercury methylation decreases with increasing concentrations of iron, which the researchers write is “a variable not previously considered in mercury methylation studies.”

The Northmet SDEIS demonstrates a net reduction of the level of mercury downstream from the Embarrass and Partridge Rivers. This isn’t modeling. PolyMet has been testing for over five years at a remote plant site to provide solid evidence. For Arneson to imply that PolyMet would even consider harming my children and grandchildren is unfathomable.

Regional differences

My wife and I love to watch home-renovation programs on HGTV and are often flabbergasted when a house that would sell for under $200K in Minnesota is listed for $700K to $900K in Boston. Imagine what would happen if state/federal legislators decided to enact laws that disregard any regional differences and set your property tax at the highest home value.

This is what is happening to the Minnesota mining industry.

Minnesota’s stringent 10 mg/L sulfate standard was enacted to protect wild rice. According to the MPCA, no other state has this wild-rice water standard.  I do not hesitate to tell you that the MPCA study validates this level in waters that contain no iron.

The Minnesota Department of Health states 400 mg/L is safe for infant formula in its 1999 publication Sulfates in Well Water. But the 10mg/L wild rice sulfate standard will force towns and cities to spend hundreds of millions of dollars for unnecessary upgrades to water treatment facilities that cannot meet the standard.

In a recent Star Tribune article, Kathryn Hoffman, an attorney with nonprofit law firm Minnesota Center for Environmental Advocacy, commented that the state’s environmental standard remains in place because the state’s research supports it. “And this is science,” she said. “Not democracy.”

This is science, chemistry to be more accurate. The 10mg/L sulfate standard is defensible in waters that contain no iron content. But this is not Boston. Iron Range waters are loaded with iron. The 1973 standard was enacted without taking regional differences into account.

Enormous benefits, without harming environment

Why do environmentalists fail to mention the enormous tax benefits of mining an estimated $3 trillion in copper, nickel and precious metals? Revitalized mining will help pay for improving our schools, our roads and many other projects important to voters, even cleaning up rivers in the metro area. Minnesota legislators are running out of ways to tax you to pay for it all.

If I thought that children and grandchildren of mine or yours are in danger, I would not support PolyMet for a second. The PolyMet NorthMet mine will meet all current environmental standards. Modern scientific evidence clearly demonstrates that mining in the iron-rich Minnesota Arrowhead region can be done without harming wild rice or increasing mercury levels.

Iron Range legislators were right to intercede with Gov. Mark Dayton. The governor needs to demonstrate the courage to direct MPCA to update Minnesota’s antiquated and unreasonable “one-size-fits-all” 1973 wild-rice sulfate standard.

I can do nothing to prevent environmentalists from writing offensive articles other than to make a heartfelt appeal to work together with the mining industry to create a win-win scenario for all of Minnesota.

Harlan Christensen is a Polymet Shareholder, formerly of Duluth, who resides in the Twin Cities.


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