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St. Louis River estuary ‘cleanup’ ignores the source of the toxic mess

If the St. Louis River is to be cleaned up, responsible agencies must oversee the entire watershed.

In its April newsletter, the Natural Resource Research Institute (NRRI) at the University of Minnesota, Duluth, touted its role in new efforts to clean up the St. Louis River estuary. The newsletter lists past damage to the estuary including wood waste, PCBs, mercury, filling of wetlands and harm to life within the habitat.

Anne Stewart

However, cleaning up polluting sources at its mouth will not save the river unless the entire watershed is protected. NRRI’s activities at the river’s terminus are at odds with its activities at the headwaters, where NRRI geologists and economists actively promote copper mining. Dean M. Peterson, a UMD geologist, is also an officer of Duluth Metals, a company developing the Twin Metals mining operation near Ely. 

The St. Louis River, pristine at its source at Seven Beavers Lake in the Superior National Forest, flows westward through a wetlands area acquired under the federal Weeks Act (enacted in 1911) to preserve and protect watershed headwaters. The wetlands may soon be diminished. Rock peppered with copper-nickel and precious metals underlies the wetlands. PolyMet Mining plans to acquire a single parcel of 6,650 acres of Superior National Forest by trading to the U.S. Forest Service five privately held tracts scattered throughout. Some 912.5 acres of wetlands will be mined, but the effects will extend into the surrounding wetland. PolyMet will restore wetlands elsewhere as mitigation, but not necessarily in the St. Louis watershed, which means a loss of wetland area for the watershed.

Wetlands store water, filter water, and provide habitat.

Twin Metals will mine in the Rainy River watershed, but tailings will be deposited in the St. Louis River watershed not far from PolyMet. Sulfate pollution and wetland destruction will occur in the headwaters even before the river continues southwest into the heart of the iron mining region to receive treated municipal waste water and seepage from tailings basins and mine pits. Mercury will be added from Iron Range mines and airborne particles from coal-fired power plants.

Threat to plants and people

Sulfates plus mercury in the river system threatens wild rice and humans.

While mining planners promise to adhere to a maximum discharge of 10 mg/L of sulfates — a maximum that protects wild rice — any added load to an already contaminated river will do harm throughout the watershed.

Retired biology instructor and scientist Len Anderson, who lives downstream on the Fond du Lac Indian Reservation, sees methylation of mercury by sulfates as a large problem that lowering sulfate discharge levels will not solve. Mercury methylation is brought about by sulfate-activated bacteria that bind with the mercury in water to create methylmercury, a toxic form of mercury that is absorbed by organisms. Starting at the bottom of the food chain, it accumulates in greater amounts as it is consumed by each organism moving upward in the food chain – all the way to humans. 

In a study released in November 2011 by the Minnesota Department of Health, 10 percent of newborns tested in the Minnesota Lake Superior Basin had levels of mercury that exceeded EPA dose limits of 5.8 ugl/l. Wisconsin had 3 percent and Michigan 0 percent.  In other words, the lake area being fed by the St. Louis River had the highest mercury levels.

The Minnesota Pollution Control Agency (MPCA) withdrew from the study, a spokesperson explained, because modeling was “not sufficient to give the right answer” to relationships between such things as sulfates and mercury.

According to Anderson, any water containing more than 3 mg/L of sulfate may set off the methylation process. Fast-moving water over sand, clay or other mineral substrate is oxygenated and prevents methylmercury-creating bacteria from acting. But once the water hits slow-moving backwaters or receding floodplains, the bacteria may become highly active.

Anderson says that once you’ve reached 8 mg/L of sulfates in a watershed, it doesn’t matter how much higher the sulfate level, the methylation machine creating methylmercury has been set in motion big time. Downriver, the sulfate level may be lower than 8 mg/L, but when the water carrying higher concentrates of sulfates arrives — in beaver ponds, lakes, or river backwaters and the estuary — it sets off the methylation process. The entire downstream watershed is affected.

Generous variances

The MPCA is generous in giving discharge variances to mining companies – as it did to Mesabi Nugget – located in the headwater streams of the St. Louis River. In March, however, the EPA reversed its approval and the MPCA must resubmit the variance for approval.

The MPCA is one agency responsible for permitting new mines. How responsibly it enforces standards is important. In 2006, the Duluth League of Women Voters released “Examining a State Agency, Minnesota Pollution Control Agency,” a study that showed that in the 1970s the MPCA Citizens Review Board was populated with people with environmental and scientific interests. This changed. The agency became “‘customer focused,’ customers being, by and large, those seeking pollution permits.” Like the revolving door between political officeholders and lobbyists, the relationship between a regulating agency and those it oversees can become blurred.

A case in point: Brad Moore, executive vice president of environmental and government affairs at Polymet, is a former MPCA commissioner (2006-2008). His duties include helping his company seek permits from the MPCA.

If the St. Louis River is to be cleaned up, responsible agencies must oversee the entire watershed. Attention must be given to upstream polluting, water drawdown for processing uses, hilltop removal, and wetland fragmentation and destruction.

Land and water areas may be reclaimed, but they cannot ever be restored to their original state.

Anne Stewart, a freelance writer and author whose work has appeared in Boundary Waters Journal and other publications, lives next to Superior National Forest land and near proposed copper mines.


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Comments (6)

  1. Submitted by THOMAS REYNOLDS on 04/10/2014 - 12:16 pm.


    I often find that environmental researchers predict behavior of geologic formations as being inert and that any disruption causes environmental damage. The problem as I see it is that geologic formations are always changing and are never inert. As these formations change so does their compositions and we have a natural breakdown in compounds which leach into the environment.

    I do agree that mining does disrupt a status quo but responsible mining also can and does give rise to more benefits than harm to the environment.

  2. Submitted by Elanne Palcich on 04/10/2014 - 12:50 pm.

    Mr. Reynolds–Geologic

    Mr. Reynolds–
    Geologic formations are inert before they are blasted, crushed, and ground into powder. Geologic formations on their own change slowly over millennia–unless there’s some kind of major disruption like a volcano.
    As far as mining companies being responsible, where is the track record? Exactly what positive benefits to the environment are you talking about? Open pits, waste rock piles, dikes and tailings basins? Destruction of forests and wetlands? Use and pollution of our water resources?
    History shows that taconite mine operations have been polluting the St. Louis River watershed for the past 60 years, and that our agencies are doing little, if anything, to force these companies to comply to existing standards and/or to clean up legacy pollution. Instead the regulatory agencies grant “variances’ which allow the mining companies to continue polluting if they claim it is either too costly to install the best available clean-up technology, or if there is no proof that such technology will actually work within existing operations.
    The pollution record of the taconite mining industry, along with the inability of our agencies to properly regulate the industry, should clearly demonstrate the need to place a moratorium on all proposed copper-nickel mining. Now that would be responsible.
    Thanks for the great article, Anne.

  3. Submitted by Joe Musich on 04/10/2014 - 03:57 pm.

    My disappontment and ..

    state of discouragement have only been amplified by further reporting of the connections mining to the mpca.

  4. Submitted by Joe Musich on 04/10/2014 - 03:56 pm.

    Goliath seems to be winning …

    the action regarding mining in minnesota once again. It is pretty clear that the power of miining coupled with the subjucation of northern minnesota politicans has subverted logic and science yet again. Any discussion suggesting that moving ahead with this horrendous project is demeaned,discounted,minimized,bashed,repressed, outspent,trivialized,twisted,etc.
    It sort of like the Asian wars or the implmentation of nuclear power. There were warnings regard7ng the consequences. The lessons of hubris are going unheard.

  5. Submitted by Pat Brady on 04/10/2014 - 11:57 pm.

    Who are these regulators?

    As far as I can tell the permit for Polymet and behind them Twin Metals is now in the hands of the DNR and MPCA.
    These folks are appointed by the Governor? Confirmed by whom?
    Who are these folks and what are their backgrounds?

    I am seeing our MN polticans not asking hard questions,but just passing the buck to these agencies that are less than transparent.
    And the public for the most part are unaware these folks hold the keys to the kingdom for gobal mining interest over the rights of Mn citizens for generations.

  6. Submitted by Todd Hintz on 04/11/2014 - 08:51 pm.

    Mr. Reynolds

    A study of Montana’s mining history shows it would have been better to buy the ore on the open market and give it away than let companies come in and mine their ore. That’s how expensive the environmental damage is. Mining companies would typically vote bonuses for the executives right before they declare bankruptcy so they could avoid cleanup costs for their operation.

    It’s a classic case of privatizing profits and socializing costs. The state of Montana is left with the cost of cleaning up toxic waste accumulating behind dams and watersheds destroyed from silt, heavy metals, and fill.

    Let’s not repeat their mistakes. Let’s preserve what is left of our environment.

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