Gogebic Taconite Mine

The Gogebic Taconite Mine is a proposed open-pit iron mine in Wisconsin’s Penokee Hills.

The Florida-based company Gogebic Taconite (GTAC) has mineral ownership of a 22-mile long area in Ashland and Iron counties. GTAC has drilled exploratory holes in the region and has stated its intent to begin mining as soon as the company receives a permit from the DNR.[1]

On June 17, 2013, GTAC submitted their “Notice of Intent” preapplication for mining, along with their bulk sampling plan, to the DNR.[2]

In March 2013, a new iron mining law passed that significantly changes DNR’s permit review process.[3]

Key Points

  • GTAC is proposing to generate more than enough waste from the mine to bury the entire city of Green Bay under a pile 10.5 feet deep, or to put the entire city of Milwaukee 6 feet under.[2] This waste will contain the materials that cause “acid mine drainage,” as well as other hazards such as mercury and arsenic.[4]
  • The proposed mine sits directly above the Kakagon Slough on the land of the Bad River Tribe, which has been named a “Wetland of International Importance” in keeping with the Ramsar Convention. It is the largest remaining wild rice bed on Lake Superior, and could be severely damaged by sulfate pollution and other pollution from the mine.
  • Geologically similar iron mines in Minnesota have been shown to increase risks of mesothelioma – a rare cancer currently linked only to asbestos exposure. There is evidence of asbestos-like material near the proposed mine site.[5]
  • Taconite plants are the largest source of mercury in the Lake Superior basin,putting them at odds with a binational target set by the U.S. and Canada to eliminate mercury releases into the basin by 2020.[6] The existence of mercury-containing minerals the around the proposed Gogebic mine has already been confirmed, and measures to control mercury emissions from taconite mining are either not available or difficult to implement.[7]
  • Mines like the one Gogebic Taconite proposes to build use enough water to potentially reduce the available supply of clean water in the area. They also use significant amounts of power and natural gas, which would mean new transmission lines and pipelines across the Northwoods.
Clean Wisconsin's Work

Clean Wisconsin is concerned about the potential mine. We encourage a thorough environmental analysis before further development in the permitting process. This mine could have harmful effects on the wildlife, forests, soils and waterways in the area. At Clean Wisconsin, we fully support job creation, but we realize that forcing residents to decide between protecting natural resources and promoting economic development is a false choice. Simply said, we don’t need to give away citizen rights and our natural resources to create jobs. That is especially clear in Wisconsin, where tourism is a $2.6 billion industry and our pristine natural resources lure anglers, hunters and those seeking to recreate and enjoy our waterways from all over the country.

Clean Wisconsin Media and Materials

Questions and Answers

What is taconite? 

Taconite is a sedimentary rock containing iron ore, generally magnetite. The iron content is between 25-30%. Taconite can also refer to the processed iron ore pellets.[8]

Where is the proposed mining site located, and how large will it be? 

The mine will be sited in ancient mountains known as the Gogebic Range between Upson and Mellen in Iron and Ashland counties. It is now called the Penokee Range and is located at the headwaters of the Bad River (near Ashland). It will initially be 4 to 5 miles in length,[9] and a total of 6,744 acres in size.[2]

These 6,744 acres are primarily public lands or lands in the “Managed Forestland Program” meaning they are currently open to public recreational uses. They also include 1,028 acres of land categorized as “farmland of regional importance,” although there are currently no commercial farming operations on the land. Of the 6,744 proposed acres for the mine site, 3,122 acres have been proposed to be “disturbance acres.”[2]

How will this mine impact the economy?

GTAC has claimed that the opening of this mine would result in the creation of approximately 3,000 construction jobs and 700 direct mining jobs. They also estimate about $17.15 million in local tax revenue.[1] However, it should be noted that these jobs may not all come from the local community, and that mining jobs are generally volatile – they have been cited in Minnesota as creating economic instability in an area.[10]

Additionally, any destruction of the natural environment of an area reduces the ability of the land to hold and attract residents and visitors. This, along with the inevitable air and water pollution negatively affects the economy. The tourism industry is heavily reliant on the pristine nature in northern Wisconsin and currently provides 300,000 jobs. There are more job openings in the Great Lakes region from tourism, recreation and agriculture than there are from mining.[11]

What are the primary public health risks associated with this mine?

There are large number of public health risks associated with the mine. The largest of these risks are the potential for the mine to release toxic chemicals like mercury and arsenic, and the potential for the mine to cause hazardous air pollution.

What toxic chemicals could be release from this mine?

Recently, geologic testing was done on Tyler formation that will be dug up as part of the “waste rock” overlying the iron deposit. This testing confirmed that not only were there acid generating minerals present, but there is also mercury and arsenic.[4] These toxic materials will be released into the air through the extraction and processing activities at the proposed mine, and can be leached out of the rock and into the water with the help of the acid mine drainage that may occur.

Iron mines in Minnesota are already the largest single source of mercury in the Lake Superior basin, and the single biggest obstacle to be overcome for us to meet the binational targets we have agreed to with Canada, to reduce mercury releases into the basin by 95% in 2015, and to eliminate them entirely by 2020.[6] Unfortunately, measures to control mercury emissions from taconite mining are either not available or difficult to implement.[7]

What is the hazardous air pollution that could come from this mine?

Pelletizing facilities from taconite mining produce fugitive dust, which can contain asbestos-like materials, silica and other toxic compounds. Pelletizing plants can also emit toxic air pollutants such as chromium, arsenic, lead, cobalt, and manganese. Chronic exposure to arsenic can cause lung cancer, while long-term exposure to arsenic and lead can lead to central nervous system, blood pressure and kidney disorders.

The proposed mine may also release fine particulate matter, which can cause a wide range of respiratory and cardiovascular illnesses. Additionally, large mining operations need a significant amount power – sometimes even building their own power plants to fuel their operation. Regardless of where the power comes from, unless alternative fuel sources are used, coal power plants will have huge additional impacts on air quality in an area.

There is also some concern over the potential health effects of asbestos-like minerals being emitted from taconite mines.

Is there reason to be concerned about asbestos-like minerals at the proposed Gogebic taconite mine?

Yes. The Gogebic Iron Range is geologically similar to the Mesabi Iron Range in Minnesota, where a taconite mining community in has been shown to have abnormally high incidence of mesothelioma, a rare cancer currently linked only to asbestos exposure.[12]

The results of a study into this issue have only started to come back recently, but even the preliminary results have been enough to tie health problems directly to the taconite industry.  In a recent report to the Minnesota legislature, the researchers noted that three important diseases are present in numbers that are higher than expected: mesothelioma (nearly 3 times higher than expected), lung cancer (higher by 20%) and cardiovascular disease (11%). They went on to say that “the longer people worked in the taconite industry, the higher their risk for mesothelioma. The risk went up by about 3% per year worked.” [5]

A prior geologic assessment of the Gogebic range confirms the similarity with the Mesabi range, with amphibole materials like to those investigated in Minnesota being present near the proposed Gogebic mine site.[13]

Unfortunately though, the metamorphic patterns in the Gogebic range are not well known, so it isn’t known whether they are present at the proposed mine site or not. It is similarly unknown if those materials are present in the rock targeted for bulk sampling by GTAC.

What are the environmental dangers associated with this mine?

The GTAC mine could have significant impacts on the environment, both from the direct disturbance of the land in the region, and from the pollution that could result from the operations. Water pollution is a special concern in this particular case, because the proposed mine is located near the sensitive Bad River watershed, which contains 72 rare and endangered plants and animals.[14]

The potential of the proposed mine to produce toxic acid mine drainage is also a serious threat to the ecosystems in the area, especially since both the rock around the iron deposit and sections of the iron deposit itself are known to contain acid-generating materials.

The proposed mine is also directly above the Kakagon Sloughs, which is a designated “National Natural Landmark” and “Ramsar Wetland of International Importance.” The Sloughs contain the largest remaining wild rice bed on Lake Superior, which the Bad River Band of the Lake Superior Tribe of Chippewa Indians own and depend upon. Wild rice is very sensitive to changes in water levels and water quality, such as the presence of sulfates that get into the environment when mining activities disturb natural sulfate deposits.

Sulfates also contribute to the conversion of mercury from inorganic forms to the more dangerous the highly toxic methylmercury form (see the Mercury Pollution Background page for more information on different types of mercury).

Finally, if the power needed for the mine comes from existing power plants, new transmission lines will be needed which gives transmission companies eminent domain to build on private property and sometimes span sensitive wetlands.

What exactly is acid mine drainage?

Acid mine drainage is when acidic water flows from mine sites. Typically, this happens when sulfur-containing rock is mined and reacts with water and oxygen, produces hydrogen, and lowers the pH. The taconite mine will not directly mine sulfurous minerals, but the waste rock that is removed and exposed to air can cause acid mine drainage. This drainage can enter the environment, acidifying the water and soil, and causing toxic metals to leach from mine waste. This affects the habitats of many different species, often making conditions too difficult to live in.[15] For more information, see our factsheet on Acid Mine Drainage and the Gogebic Taconite Mine.

Now that GTAC has submitted a pre-application for the proposed mine, there is no longer a question about whether acid will be generated at the site GTAC mine site. The project boundaries identified in the pre-application are documented to contain pyritic shale both in the Tyler Formation that overlies the iron formation, and in a “3 meter-thick basal unit of pyritic shale” in the Yale Member of the iron formation itself.[16]

Quick Facts
  • Former shaft and pit mines in Lake Superior basin have affected the regional ecosystem.[17]
  • There are currently 72 rare and endangered plants and animals in the Bad River watershed. It also contains 28 different plant communities. These animals include waterfowl, songbirds, woodland birds and several fish species.[14]
  • The Bad River watershed empties into Chequamegon Bay, one of the largest undeveloped fresh water estuaries in the world.[18]
  • The mine would alter height and pollution levels of the water, potentially damaging the wild rice grown and harvested in the area, along with other plants and animals.[19]
  • Nearly every Superior coastal tribe has been affected by metal mining in the past.[19] Acid mine drainage could result from the Gogebic mine, harming the environment and wildlife in the area as sulfur from the waste is exposed to the air.[20]
  • The Penokee Range is the source of drinking water for the towns of Ashland, Mellen, Highbridge, Marengo, Odanah and Upson.
  • Iron mines in Minnesota are the largest single source of mercury in the Lake Superior basin,[6] and a 2012 study showed that one of every 10 babies born in the Lake Superior region of Minnesota have unsafe levels of mercury in the bodies.[21]
Wisconsin Data, Trends, and Legislation

The last metallic mine in Wisconsin ended operation in 1997. The GTAC mine would be our first open pit mine in over a decade.[22] Thus far, GTAC has been granted permission to drill eight exploratory holes in the area to test the iron ore. But before they proceeded with a permit application, the company pushed a new iron mining law through the state legislature to expedite the process of granting permit. For detailed information on the new law, go to the Iron Mining Legislation page.

  • The area around the Gogebic Iron rangehas been heated and compressed, making it the hardest formation in the region, requiring more energy to mine.[23]
  • A layer of Tyler formation is found above the iron,[23] which is known to contain mercury, arsenic, and other toxic pollutants.[4] GTAC plans to remove this layer as overburden, developing even higher waste levels which could enter our waterways (including the Chequamegon Bay) and pollute the surrounding area.
  • Pyritic shale is known to exist in the Tyler formationand in the iron formation itself[23] Once removed as waste, it will be exposed to air and is capable of causing acid mine drainage. Acid mine drainage would be extremely damaging to the area.[15]
  • The GTAC mine has been presented to the public as only 4 miles long. However, for this open pit mine to exist, over 4 square miles are being established to hold the tailings pond. Room is also needed for the power plant to run the mine, access to roads in the area for transportation, and a processing plant for the mined taconite. This makes the area of land affected much greater than 4 miles long – the proposed mining area is a total of 6,744 acres in size.[2] This would result in even more habitat loss for the 72 rare and endangered plants and animals living there.[22]
  • The Gogebic Range is an east-west-trending belt in the Lake Superior region. It spans the Penokean fold-and-thrust belt, which contains both deformed and undeformed rocks. It also cuts through the Marquette Range Supergroup of paleoproterozoic metasedimentary and metavolcanic rocks. Rock regions similar to it in Minnesota have been mined with devastating, lasting effects.[14]
  • GTAC claims that a total of 2,834 jobs will be created, but in the Great Lakes area many more job opportunities result from recreation and tourism in the area, not mining related jobs. There are 217,635 jobs in the recreation and tourism industries and only 10,003 in the mining industry in the Great Lakes area. Recreation and tourism jobs rely on the region staying clean, safe and filled with natural beauty.[11]

Current Law

Detailed information on iron mining legislation is located on the Iron Mining Legislation page.

Cited Resources
  1. Gogebic Taconite Mining Official Website. Web. Retrieved 2012 from http://gogebictaconite.com/
  2. Gogebic Taconite, LLC. “Preapplication Notice, Wisconsin Statutes 295.465.” June 17, 2013.
  3. Wisconsin Department of Natural Resources. “Overview of metallic mining in Wisconsin.” Web. Retrieved 2012 from http://dnr.wi.gov/topic/Mines/Metallic.html
  4. M Bjornerud, A Knudsen, and J Trotter. “Geochemical, mineralogical and structural characterization of the Tyler Formation and Ironwood Iron Formation, Gogebic Range, Wisconsin.” Prepared for the Great Lakes Indian Fish and Wildlife Commission (2012).
  5. J Finnegan Jr. and J Mandel. “Annual Report to the Legislature, Minnesota Taconite Workers Health Study.” April 19, 2013.
  6. Lake Superior Binational Program. “Lake Superior Zero Discharge Demonstration Program and Critical Chemical Reduction Milestones.” Nov. 2012.
  7. M Bernt. “Mercury and Mining in Minnesota, Minerals Coordinating Committee Final Report.” Minnesota Department of Natural Resources (2003).
  8. Wikipedia, “Taconite.” Web. Retrieved 2012 from http://en.wikipedia.org/wiki/Taconite.
  9. Gogebic Taconite. “Gogebic Taconite Mine Map.” Web. Retrieved 2012 from http://gogebictaconite.com/project.html
  10. T Power. “Economic Role of Metal Mining in Minnesota.” Prepared for: Minnesota Center for Environmental Advocacy and the Sierra Club. 2007.
  11. L. Vaccaro and J. Read. “Vital to Our Nation’s Economy: Great Lakes Jobs 2001 Report.” (2011).
  12. G. Gibbs and G. Berry. “Mesothelioma and Asbestos.” Regulatory Toxicology and Pharmacology 52 (2008) S223–S231
  13. R Marsden. “Iron Ore Reserves of Wisconsin, A Minerals Availability System Report.”  1978
  14. The Nature Conservancy. “The Nature Conservancy in Wisconsin – Protecting the Place Where Food Grows on Water.” Web. Retrieved 2012 from http://www.nature.org/ourinitiatives/regions/northamerica/unitedstates/wisconsin/the-nature-conservancy-in-wisconsin-protecting-the-place-where-food-grows.xml
  15. Clean Wisconsin, Inc. “Acid Mine Drainage and the Gogebic Taconite Mine.” (2013).
  16. W Cannon, et al. “The Gogebic Iron Range—A Sample of the Northern Margin of the Penokean Fold and Thrust Belt.” U.S. Geological Survey Professional Paper 1730 (2007).
  17. J. Ralph and I. Chau. “Strunz classificiation mineral list for Montreal Mine (Ottawa; 33 Company Mine; Trimble; Odanah; Moore; Jupiter; Bourne; Sec. 33 Mine), Gogebic Range, Iron Co., Wisconsin, USA.” Web. Retrieved 2012 from http://www.mindat.org/locstrunz-16506.html
  18. M. Dallman, B. Sapper, and C. Harrington. “The Kakagon/Bad River watershed.” Prepared for: The Nature Conservancy (1998).
  19. L. Bergquist. “Iron County Mine Proposal Pits Jobs Against the Environment.” Milwaukee Journal Sentinel (July 2, 2011).
  20. Randall Schaetzl. Iron Mining Today. Web. Retrieved 2012 from http://www.geo.msu.edu/geogmich/iron_iii.html
  21. J Meyers. “Study: 1 in 10 babies in Lake Superior region are born with high levels of mercury.” Duluth New Tribune, February 3, 2012.
  22. L. Bergquist. “Firm asks to test for ore.” Milwaukee Journal Sentinel (March 21, 2011).
  23. W. Cannon et al, “The Gogebic Iron Range—A Sample of the Northern Margin of the Penokean Fold and Thrust Belt.” U.S. Geological Survey Professional Paper 1730 (2007).
  24. Carl Sacks (2011). “Water On the Line: Gogebic Taconite’s Push to Mine the Penokee Hills.”
  25. Great Lakes Indian Fish and Wildlife Commission (2011). “Penokee Range Iron Deposit.”
  26. Great Lakes Indian Fish and Wildlife Commission (2013). “Surface waters potentially filled by iron mining given provisions of AB1/SB1.”
  27. M. Bjornerud, A. Knudsen, and J. Trotter (2012). “Geochemical, mineralogical and structural characterization of the Tyler Formation and Ironwood Iron Formation, Gogebic Range, Wisconsin.”
  28. Ron Seely. “After the mine: All that’s left is a bitter aftertaste.” Milwaukee State Journal (March 11, 2012).


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