The Twin Metals mine is a potential copper sulfide mine near Ely, Minnesota, on Superior National Forest land. There has been significant opposition to the proposed mine, most notably because of its proximity to the Boundary Waters Canoe Area Wilderness, location within a watershed that drains into the BWCA, and the air, water, light and noise pollution and traffic effects of converting a forested area bordering the BWCA into a substantial industrial mining facility. The Twin Metals mine is being attempted by Twin Metals LLC, a subsidiary of Antofagasta Minerals, itself a subsidiary of the Chilean conglomerate Antofagasta PLC, which is controlled by billionaire Jean-Paul Luksic Fontbona. The original lease is a 1966 lease to the International Nickel Corporation.
The facility would have an underground mining area accessed by two sloping tunnels, an above-ground processing factory, and a tailings dumping area that would use the dry-storage method. Twin Metals has estimated that the mine would provide 700 jobs and create 1,400 jobs in related industries and that it would operate for 25 years, mining 20,000 tons of ore per day retrieved from depths of between 400 and 4,500 feet.
The mine's leases were terminated under the Obama administration but renewed under the first Trump administration. Critics have objected to and filed lawsuits against various aspects of the lease renewal and regulatory processes.
In March 2021, President Joe Biden announced that the Interior and Agriculture departments would review Twin Metals' lease renewal and a judge ordered a pause in the lawsuit(s) until June 21, 2021, to review the Trump administration's decision to renew the leases. On October 20, 2021, the Biden administration ordered a study that could lead to a 20-year ban on mining upstream from the Boundary Waters Canoe Area Wilderness. The federal government said it had filed an application for a "mineral withdrawal", which would begin with a thorough study of the likely environmental and other impacts of mining if it were permitted in a watershed that flows into the Boundary Waters. On January 26, 2022, the U.S. Department of the Interior canceled two leases required to build and operate the mine, determining that they were improperly renewed under the previous administration. On January 26, 2023, The Department of the Interior set a 20-year moratorium on mining in 225,000 acres of the forest upstream of the BWCA. The moratorium protects the waters of the Rainy River watershed from pollution and blocks the proposed Twin Metals mine.
Iron mining has been a significant part of Ely's history, and iron mines in the Mesabi Range still account for a majority of US iron ore production. Ely now also has significant recreational business related to the BWCAW and Superior National Forest. Proponents cite the economic benefits from projected jobs from the mine; opponents assert that those might not be as expected and would last only for 25 years, and that the mine could prove to be a net economic loss for the region because of its effects on other aspects of its economy.
Proposed mine
Superior National Forest was created in 1909. The Boundary Waters Canoe Area Wilderness, which is within it, is highly protected as wilderness and was created in stages, primarily between the 1930s and 1978. In the 1960s, during the Lyndon Johnson administration, the International Nickel Company negotiated with federal officials to begin copper-nickel mining near Ely in St. Louis County, Minnesota. The proposed mine would be on land that is part of the Superior National Forest, in Minnesota's Arrowhead Region, between the Canada–U.S. border and Lake Superior's north shore. It is part of the greater Boundary Waters region along the Minnesota–Ontario border, a historic and important thoroughfare in the fur trading and exploring days of New France and British North America. The BWCA is popular for canoeing, fishing, and hiking, and is the country's most visited wilderness area. The proposed mine site is just outside the BWCA, within the Rainy River watershed, which drains into BWCA lakes, leading some to object that a mining accident could lead to contamination of the lakes within the Wilderness Area.
The proposed development is by Twin Metals Minnesota LLC, a Delaware corporation and subsidiary of Antofagasta. Twin Metals Minnesota LLC was formed in 2010 as a joint venture controlled by Antofagasta, a Chilean conglomerate controlled by billionaire Andrónico Luksic. Twin Metals' "operational headquarters" is in Ely and its corporate headquarters is in Saint Paul. Although the proposed mine is on Superior National Forest land, the mining is regulated by the Bureau of Land Management.
In December 2019, Twin Metals submitted its formal plans to state and federal officials. The documents lay out a detailed plan of the mining operation and an outline of how the company proposes to manage environmental impact. A Minnesota Public Radio report describes the operation as presented in the Twin Metals documents:
The mine would be accessed by two tunnels, 20 feet by 20 feet and 1.25 miles long, sloping downward to the ore body. Conveyor belts would carry crushed ore to the surface, where it would be processed into metal concentrates at a nearby processing plant. There would be lighting, ventilation, office space and places for employees to gather deep underground. [...] Most mining would occur from 400 feet down to a depth of potentially about 4,500 feet.
The company plans to use a system called "dry stacking" to dispose of tailings, which it says will avoid the use of water and any need for a wastewater treatment plant. Twin Metals says it can create and operate the mine safely and has submitted a plan of operations in its plan's main body, appendices, and worksheet data.
Minnesota has a long history of iron mines, but this would be one of its first copper mines. Another proposal remains under review: an open-pit mine near Babbitt proposed by PolyMet. It would be on the site of a closed iron mining operation, with plans to renovate and expand an old taconite facility to mine copper. Glencore, a British multinational commodity trading and mining company, is the majority stock owner of the PolyMet mining project.
Environmental concerns
The proposed mine and processing facility is controversial because it is to be on the shores of Birch Lake and the South Kawishiwi River, which lie in the Rainy River watershed and flow into the Boundary Waters Canoe Area Wilderness, about five miles northeast. In 2016 the Forest Service and Bureau of Land Management refused to extend two federal mineral leases to the Twin Metals mine plan, and the Forest Service proposed a 20-year mineral withdrawal and launched a 24-month environmental review of the proposal. The Trump administration reversed that decision and ended the environmental review, allowing the plans for the mine to proceed.
Tom Landwehr, who served five terms as the executive director of the Department of Natural Resources, does not oppose copper mining in Minnesota; in 2018 he worked to approve a proposed open-pit copper-nickel mine near Babbitt. But he believes that there are places where "we can't even consider mining", and when he looked at the plans for a mine so close to the Boundary Waters he said he was "just absolutely stunned". Landwehr noted that the Babbitt mine is in an existing mining area while the Ely site is not only within the BWCA watershed but is covered by forests, lakes and rivers. "It is just such a fragile site from the potential for human damages right on the edge of the Boundary Waters. They are two completely different sites, and this is one of those places where you have to say, 'Not this mine, not this site, not now, not ever.
Surface water pollution is the most often cited pollution concern. Others include light, noise, dust, air and groundwater pollution. Concern is about both the direct effects of these and the effect on property values and tourism and recreational industries due to the pristine environment of both the BWCA and the National Forest. Some studies found that pollution could be significant enough to make the mine a net economic loss for the area. Another concern is acidic drainage into groundwater from accumulated water in the mine.
Controversy over toxic waste storage
Historically, mining waste has been stored in tailings ponds, resulting in the release of toxic waste into nearby waters. In July 2019, saying "we heeded the evidence that is out there and we listened to the community concerns", Twin Metals put out a press release saying it would abandon the plan to use a storage pond, which was to be outside the BWCA watershed near Babbitt, and would instead use the dry stacking method of toxic waste storage. While generally more expensive than a conventional tailings dam, dry storage would not require the expensive construction and operation of a pipeline to ship tailings out of the BWCA watershed. Twin Metals’ chief regulatory officer Julie Padilla said, "The key is, it removes that tailings dam. It removes any potential for failure of a dam and spillage in that sense, which is obviously one of the big concerns about this project and others."
The state Department of Natural Resources has questioned whether the method can work in Minnesota's climate. MinnPost wrote that documents show that, when the DNR approved dam safety permits for the tailings pond to be used in the Babbitt PolyMet mine, it noted, "If dry stack material becomes wet—but isn't fully submerged in a tailings pond—it can leach heavy metals that can wash into nearby soil and water." The agency also said dry stack tailings can create a toxic dust that poses environmental risks. Padilla said that Twin Metals can deal with cold and wet weather by using the dry stack method only when weather allows and putting the tailings back into the underground mine, as has already been planned for about 50% of the tailings, during bad weather.
A spokesman for the Minnesota Center for Environmental Advocacy said that dry stacking is generally better than a tailings basin and dam but the department needed to see more specifics on the plan. Save the Boundary Waters called the decision to store waste at the project site "going from bad to worse". Of the four mines that Twin Metals has cited as successfully using the dry staking system, it said, "All are still in operation. This is important because it sometimes takes a decade or two after mining has ended for the full scale of water pollution to become evident. Nonetheless, all mines have polluted and may continue to pollute surrounding surface water, groundwater, or both."
Obama administration