Does the US Need Minnesota Nickel?

Based on the US Geological Survey (USGS) 2025 report (pubs.usgs.gov/periodicals/mcs2025/mcs2025-nickel.pdf), the proposed Tamarack Mine will make NO difference in the global supply of nickel but only serve to increase profits for Rio Tinto, a large foreign mining company. The USGS report shows that currently, only 0.22% of the world’s supply of nickel comes from the US (primarily from Michigan Eagle Mine).

In fact, the US only possesses 0.24% of the worldwide reserves of nickel (in Michigan and Tamarack). Right now, the Eagle mine is shipping their nickel to Canada for processing where it sold on the global markets. It is likely that Talon will do the same as nickel is engineered out of EV batteries (see tamarackwateralliance.org/evs.html). Instead of shipping this nickel onto global markets / China, should we not save our meager reserves for the future? Are the profits for Rio Tinto worth the destructive impacts of sulfide mining?

Sulfide Mining is Destructive and Dangerous

Sulfide ores contain metals (such as nickel, copper and cobalt) that are bonded to sulfur, forming sulfide minerals. The amount of sulfur in these ores can range from 7% to as high as 70%. However, the usable metal content is much lower. In the case of the proposed Tamarack/Talon/Rio Tinto mine, nickel comprises only 1.8% of the ore (per the Talon Preliminary Economic Analysis document). Thus, much more sulfur is mined than nickel. This excess sulfur is waste and discarded into the environment.

When sulfide mining waste is exposed to air and moisture, a chemical reaction occurs that generates sulfuric acid that migrates into the surrounding environment and, through leaching, releases heavy metals present in the waste rock, pit walls, and tailings basins of mining operations. The sulfuric acid along with dissolved heavy metals released onto the land will seep into the rich aquifers below and then into streams and lakes at levels that are toxic to fish and other aquatic life. This type of pollution is commonly referred to as Acid Mine Drainage (AMD) and has the potential to devastate entire ecosystems. The close proximity of sulfide mines to valued water bodies such as lakes and rivers of the Mississippi watershed,intensifies the magnitude of this issue. All of the water bodies in the Tamarack area are linked by multiple aquifers.

To make matters worse, the sulfide mining industry has a poor history of stewardship, integrity and accountability. To date, no sulfide mine has been able to operate without causing some form of pollution in the surrounding environment. Talon Metals (who plans to mine in Tamarack, Minnesota) points to the Flambeau Mine in Wisconsin and the Michigan Eagle Mine as model cases of environmental stewardship; however, both sites have very serious environmental issues (see below).

Sulfide Mines Lead To Contaminated Water

Many organizations have noted that anytime a sulfide mine has been built in a water rich area, the water has been contaminated. Of course, new mines open over time so no single reference can ever be "up to date" in support of this statement. Nevertheless, we can show that no mine has been found to not contaminate the local water based environment, particularly in wetland areas.

It is interesting to note that, from the EPA superfund website, 42 past mines in the US are now EPA Superfund sites. The number was much larger in the past. (see www.epa.gov/superfund/national-priorities-list-npl-sites-state. Why are we using taxpayer dollars to pay for the sins of the (often foreign) mining companies. We need stronger mining laws to prevent polution!
The research paper available at earthworks.org/wp-content/uploads/2012/08/Porphyry_Copper_Mines_Track_Record_8-2012.pdf was reviewed by Dave Chambers Ph. D., and the Center for Science in Public Participation (CSP2). The report considered state and federal documents and a federal database for fourteen copper porphyry (igneous rock) mines operating in the U.S. with respect to three failure modes: pipeline spills or other accidental releases, tailings spills or tailings impoundment failures, and failure to capture and treat mine seepage. The mines were chosen based on an operating record of more than five years and represents 89% of U.S. copper production in 2010. The research shows that all of the mines experienced at least one failure, with most mines experiencing multiple failures and that copper porphyry mines are often associated with water pollution associated with acid mine drainage, metals leaching and/or accidental releases of toxic materials. These failures resulted in a variety of environmental impacts, such as contamination of drinking water aquifers, contamination and loss of fish and wildlife and their habitat, and risks to public health. In some cases, water quality impacts are so severe that acid mine drainage will generate water pollution in perpetuity. Many of the currently operating copper porphyry mines are located in the arid southwest, where precipitation is limited, and communication between surface and groundwater resources is limited. While beyond the scope of the analysis in this report, more significant impacts could be expected at mines in wetter climates, with abundant surface water and shallow groundwater.
Additionally, research (Kuipers, J.R., Maest, A.S., MacHardy, K.A., and Lawson, G. 2006. Comparison of Predicted and Actual Water Quality at Hardrock Mines: The reliability of predictions in Environmental Impact Statements) shows that mines with high acid generating potential and in close proximity to surface and groundwater are at highest risk for water quality impacts. This report studied 25 operating hard rock mines and their EISs. All predicted compliance with water quality standard within their EISs however pollution from 85% of mines near surface water and 93% of mines near ground water exceeded water quality standards. In addition, 89% had inaccurately predicted that they would not create AMD.

Examples of Acid Mine Drainage (AMD)

Acid runoff from the Summitville Mine in Colorado killed all biological life in a 17-mile stretch of the Alamosa River. The site was designated a federal Superfund site, and the EPA has spent over $210 million on clean-up.

Zortman Landusky mine in north central Montana filed for bankruptcy in 1998 leaving the state of Montana with the liability for $33 million in long-term water treatment and reclamation costs.

Torch Lake in Houghton County, MI is a superfund site. Copper mining activities in the area from the 1890s until 1969 produced mill tailings that contaminated lake sediments and the shoreline. Fish were found with cancerous tumors and high levels of copper, arsenic, mercury and PCBs. Remediation efforts started in 1998 and continued through 2006 – EPA updated cleanup plan Nov 2024 Note here that environmental damage may not be recognized until nearly 20-30 years after mine closure. It often takes a quite a bit time for the toxic materials to seep into sensitive areas and for the chemical reactions noted to occur.

MPCA (Minnesota Polution Control Agency) recently announced that Birch Lake near the Boundary Waters has excessive sulfate in its water (impaired). The Dunka taconite mine (closed in 1991) waste rock piles, which are 80–100 feet high and extend for almost a mile, have been leaching metals into the streams and wetlands that flow into Birch Lake. Several lakes and rivers upstream of the Boundary Waters Canoe Area Wilderness are contaminated with sulfate, which causes more mercury in fish and kills manoomin (wild rice), according to the MPCA and several citizen-led sampling efforts. Waters downstream of past and present iron mines exceed standards for sulfate levels designed to protect the environment.

The Northern Lakes Scientific Advisory Panel, or NLSAP, monitors (sulfate based) water pollution in Voyageurs Park and the BWCA in cooperation with the MPCA and have measured high levels of sulfate. See the video at https://www.youtube.com/watch?v=ZW8p640wNno for more detail.

Thus we have not found a high sulfide Nickel / Copper mine in wetland areas that has not polluted. Some people raise the question as to whether the Wisconsin Flambeau mine or Michigan Eagle mine have polluted the local environment or not.

Flambeau Mine Wisconsin

The Flambeau Mine is sometimes presented as an example of a clean sulfide mine. This mine was a very small open pit mine (32 acre pit) on a 161 acre mine site which operated for only for 4 years. Despite the short exposure to sulfide mine contamination, significant issues exist.

Here we note that the federal district court found that the mine discharged copper contamination at levels exceeding state standards www.casemine.com/judgement/us/5914f59aadd7b0493498b3f0). However, the Seventh Circuit Court of Appeals then ruled that this case could not proceed further, since Flambeau was entitled to a "permit shield" because it had no notice its state permit wasn’t valid so was entitled to rely on that permit. In other words, the State of Wisconsin approved the contamination. And of course, the court did rule that the mine did release pollution.

Although the state of Wisconsin considers the Flambeau Mine a successful reclamation, significant contamination of the surrounding area has been documented. Specifically, surface water runoff from the mine site does not meet Wisconsin surface water quality standards. Runoff is polluting a stream which flows into the Flambeau River. Multiple water samples between 2004 and 2008 show significantly elevated levels of copper, exceeding standards. Studies show that the stream is almost devoid of life, including vegetation and fish. Researchers believe this is because of the high metal levels. At one location, the copper level was approximately 10 times the acute water quality standard, and the zinc level is approximately twice the acute water quality standard. Copper and Zinc combined impact on aquatic organisms is greater than that of either by itself. (wisconsinrivers.org/flambeau-mine-closure-statement/)

One of the difficulties facing the metals-mining industry has been its inability to predict the quality of the water mining will leave behind. The Flambeau mine is a case in point. The mine permit application predicted the level of manganese in water entering the Flambeau River would be a quarter of what it actually is (between 2,000 and 2,500 micrograms per liter). The Environmental Impact Statement painted an even rosier picture, assuring the public that the highest level of manganese within the backfilled mine pit would be 400 micrograms per liter; the actual level is as high as 40,000 micrograms per liter in one area. The groundwater standard for manganese is 300 micrograms per liter, set to protect drinking water.

According to Flambeau’s permit application, manganese levels are likely to remain high for more than 4,000 years. Wisconsin (and Minnesota) law allows mining companies to pollute the groundwater at mine sites, and Flambeau’s polluted groundwater does not violate the law. But 4,000 years is a long time, and we cannot know how conditions will change over that kind of time frame. This is pollution that has been bequeathed to future generations and most likely to a future civilization that does not have access to our records. Is this really what we want to emulate in Minnesota?

In addition, consider:

This independent work was done by experienced PhD scientists and demonstrate significant pollution from the Flambeau Mine. Indeed, the Flambeau Mine Corporation does not deny any of this nor do they produce additional results to argue an opposite claim.

The issue is that the state of Wisconsin failed to properly baseline the area and did not implement monitoring at points susceptible to sulfide contamination. As such the state of Wisconsin refuses to acknowledge that the pollution was caused by the mine but claims that these events "could have" been present prior to mining. Nevertheless, local observers beg to differ. A significant failure by the state DNR DOES NOT mean the Flambeau Mine is clean!

Eagle Mine Michigan

The Eagle Mine is still in operation and historically we see that AMD often does not manifest for a number of years after closure.

However, even now given just a few years of operation, we see significant anomalies in monitoring when looking at the official mine report to the Michigan Government. Consider the document: www.eaglemine.com/_files/ugd/c6167e_568f076601bc48e7a02b54f222b4165a.pdf.

Eagle Mine Anomalies Report listed over 20 monitoring situations that show levels of pollution and water chemistry changes outside the planned benchmark range. For example, one water level monitoring point showed the water level was 2.8 feet below the calculated minimum baseline level. Mine attributed this drop in water levels to two main sources; pumping of the mine services well and groundwater infiltration into the mine. This drop in water levels is then due to an average pumping requirement of 80,000 to 150,000 gallons a day from the mine and service wells. If 2.8’ drop is seen at these pumping rates, what happens when Talon estimates over 2,300,000 gallons pumped per day in Tamarack?

Other examples of Eagle Mine Anomalies Reported include:

Many monitoring points showed sulfate levels 1500 times higher than the MN standard for sulfates in wild rice environments
Eagle mine reported a decrease in bird and fish populations
Location QAL024A had benchmark deviations in bicarbonate alkalinity, chloride, nitrate, and sodium.
Nitrates were detected above the benchmark during all four sampling quarters in 2022 at monitoring wells QAL060A and QAL061A
Location QAL062A had results for pH, alkalinity bicarbonate, chloride, nitrate, and sodium that were outside calculated benchmarks for each sampling event in 2022
Bicarbonate alkalinity, chloride, nitrate, and sodium were above benchmark levels at QAL063A
QAL066D had results for iron, bicarbonate alkalinity, and sodium that were above benchmark levels for all the sampling events in 2022
Location QAL067A had benchmark deviations for chloride, sodium, bicarbonate alkalinity, sulfate, and nitrate for all 2022 sampling events and Calcium, magnesium, potassium, and hardness were also above established benchmarks for at least two consecutive Q2 annual sampling events
.... And the list goes on …

Eagle Mine does a very poor job at managing dust – a possible cause of the water contamination demonstrated in the above referenced Eagle Mine Exception report. After including an air filtration system in its original permit, Eagle sought to have it removed in 2013, which the MDEQ approved, blowing a plume of unfiltered mine emissions out over the Salmon Trout River and the Yellow Dog Plains. No stack monitoring is taking place, and the emissions have not been measured since September 2014, before the mine was in full operation. (Source: Mining Action Group savethewildup.org/about/eagle-mine-facts/ and savethewildup.org/2013/03/air-filtration-necessary-on-eagle-mine-air-stack-to-keep-air-clean/).

The Eagle Mine TDRSA (Temporary Development Rock Storage Area) is lined with both a primary and secondary lining. A leak detection system is installed between the liners to monitor primary lining integrity. A total of approximately 55 gallons of water was purged from the leak detection sump in 2020, a larger volume than 2019. Thus we see that the lining system does leak after only a few years of operation. The leak levels are currently very small at this point but as noted in the document, increasing slightly over time.

Indeed one cannot find a Sulfide Mine that is not damaging in a wet environment.

Sulfide Mining and Methylmercury - Don't Eat The Fish!

Once introduced into the environment, sulfates interact with sulfate-reducing bacteria to produce the more bio-toxic form of mercury, methylmercury, a known neurodevelopmental toxin. Atmospheric mercury (Hg) is primarily produced by Taconite processing plants and coal-fired power plants (particularly from North Dakota). Atmospherically derived Hg must be methylated prior to accumulating in fish. Sulfate-reducing bacteria are the primary methylators of Hg in the environment. As such, when mine related sulfur from either water or airborne contamination settles in wetland areas, natural sulfate-reducing bacteria will convert mercury into highly toxic methylmercury.

Methylmercury is a highly toxic fat soluable substance and can accumulate in the food chain, primarily in fish. As the methylmercury is stored in the fatty tissues, concentrations of this toxin increases as you move up the food chain. This results in fish consumption limits on many Minnesota lakes.

See list of Minnesota Impaired Waters: https://www.pca.state.mn.us/air-water-land-climate/minnesotas-impaired-waters-list
Minnesota Lake Finder for more detail: https://www.dnr.state.mn.us/lakefind/lake.html?id=01002300
Fish consumption guidance can be found here: https://www.dnr.state.mn.us/lakefind/fca/report.html?downum=01002300

Note also that Methylmercury can cause a wide range of health effects, including:

Neurological damage (e.g., tremors, seizures, memory loss)
Kidney damage
Cardiovascular problems
Developmental problems in children (e.g., brain damage, motor coordination difficulties

A recent study “Mercury in Newborns in the Lake Superior Basin” showed that ten percent of tested newborns had concentrations of Mercury above the reference dose. Babies born during the summer months were more likely to have an elevated mercury level. suggesting that increased consumption of locally caught fish during the warm months is an important source of pregnant women's mercury exposure in this region. (https://www.health.state.mn.us/communities/environment/fish/techinfo/newbornhglsp.html).

Karen Wetterhahn, a chemistry professor at Dartmouth College, died from mercury poisoning in 1997 due to accidental exposure to methylmercury. A few drops of the highly toxic compound seeped through her gloves during a lab experiment. This led to her death about a year later (https://en.wikipedia.org/wiki/Karen_Wetterhahn)

Sulfide Mining Perpetrates Environmental Injustice

The existence of a sulfide mine in an area harms communities. The inevitable contamination of local water will negatively impact the wild rice beds that are currently used to sustain many in the community. In addition, fish and wildlife are negatively impacted.

Contamination from the proposed Talon Tamarack mine from wind blown dust, water contamination will have a long lasting impact on the local environment.

Property values drop as nobody wants to buy property that is or will certainly be contaminated in the future. Who wants property next to a toxic mine?

Sulfide Mining Threatens Tribal Wild Rice Resources

Minnesota ranks #1 in the United States for wild rice production, both naturally grown and cultivated Wild rice is very sensitive to sulfide contamination.

Anishinaabe seasonally harvest tens of thousands of acres of wild rice in Northeastern Minnesota’s undisturbed watersheds Manoomin is sacred to their way of life.

Pristine water quality must be maintained for wild rice to germinate, grow, and survive. Sulfates bound in glacial/bedrock geology are released when the water is disturbed due to mining, endangering wild rice fields. Many lakes and streams around the Great Lakes have already lost their wild rice. Wild rice is hard to restore once it is gone.

Minnesota’s wild rice sulfate standard limits sulfates to 10 parts per million (ppm or mgL) in wild rice waters. However, many politicians are bent on weakening this standard in support of mining - destroying a national treasure.

Additional References

For more information on the dangers of sulfide mining:

Sierra Club (www.sierraclub.org/minnesota/mining/sulfide-mining)

Mining Action Group (savethewildup.org/about/sulfide-mining-101/)

Mine EPA Superfund Sites - use your browser to search on keyword "mine" www.epa.gov/superfund/national-priorities-list-npl-sites-state

Earthworks - Copper Sulfide Mining (earthworks.org/issues/copper_sulfide_mining/)

U.S. Copper Porphyry Mines Report providing 14 detailed case studies on mining polution.
(earthworks.org/wp-content/uploads/2012/08/Porphyry_Copper_Mines_Track_Record_8-2012.pdf)

pubmed.ncbi.nlm.nih.gov/23625128/
Sahoo, P. K., Kim, K., Equeenuddin, S. M., & Powell, M. A. (2013). Current approaches for mitigating acid mine drainage. Reviews of environmental contamination and toxicology, 226, 1–32. https://doi.org/10.1007/978-1-4614-6898-1_1

pubmed.ncbi.nlm.nih.gov/30476429/
Onello, E., Allert, D., Bauer, S., Ipsen, J., Saracino, M., Wegerson, K., Wendland, D., & Pearson, J. (2016). Sulfide Mining and Human Health in Minnesota. Minnesota medicine, 99(8), 51–55.

Official 2020 mine report to the Michigan Government ( www.michigan.gov/-/media/Project/Websites/egle/Documents/Reports/OGMD/2020-ogmd-eagle-mine-annual-report.PDF.