FAQ

  • What is Twin Metals Minnesota?

    Twin Metals Minnesota (TMM) is a Minnesota mining company focused on designing, constructing and operating an underground copper, nickel, platinum, palladium, gold and silver mining project in the Iron Range region of northeast Minnesota. Twin Metals Minnesota is a wholly owned subsidiary of Antofagasta plc, one of the top 10 copper producers in the world.

  • Where is the TMM Project?

    The TMM Project is located in northeast Minnesota. The mine would be located within the Maturi deposit, which is located outside the Boundary Waters Canoe Area Wilderness and approximately nine miles southeast of the city of Ely, Minnesota, and 11 miles northeast of the city of Babbitt, Minnesota. Visit our About the Project page to view a map of the project area.

  • Why mine strategic metals and critical minerals in Minnesota?

    Minnesota is home to the Duluth Complex in northeast Minnesota. In 1977, the Minnesota Department of Natural Resources estimated that the Duluth Complex contained 4.4 billion tons of ore containing copper, nickel and PGM resources. Information from Twin Metals, PolyMet Mining and other companies exploring in the area suggests that mineral resources in the Duluth Complex are much greater. Domestic and international demand for these strategic and critical minerals is projected to grow steadily over the long term, positioning Minnesota to be a world leader in supplying these metals. According to the U.S. Geological Survey (USGS) 2017 report on critical minerals, there is a growing dependence on foreign sources of critical platinum group metals. The report called out Minnesota’s Duluth Complex as a potential source of domestically produced critical platinum group metals.

  • How will the TMM Project’s strategic metals help the economy?

    Copper, nickel and platinum group metals are critical aspects of a sustainable future including construction, communications, power distribution, national defense, medicine and renewable green energy. The TMM Project would contribute to establishing Minnesota as a world leader in the production of green energy metals used in wind turbines, hybrid and electric vehicles, batteries and solar energy panels. Visit our Economic Potential page to learn more.

  • How many jobs will the TMM Project create?

    The TMM Project represents an extraordinary opportunity for economic growth and job creation regionally and statewide. Several million labor hours will be generated during construction, on par with the number of construction and related professional jobs created by projects such as U.S. Bank Stadium and Target Field in the Twin CitiesOnce operational, TMM expects to directly employ 650 people long-term in northeastern Minnesota and to create an estimated 1,300 spinoff jobs in other industries. Learn more on our Creating Local Jobs page.

  • Will the construction jobs be union jobs?

    Twin Metals looks forward to working with Minnesota’s labor force at the appropriate time to develop a Project Labor Agreement establishing the terms of employment for construction of the TMM Project. We are grateful for the public support many unions have expressed for our project and our industry.

  • Will the mining jobs be union jobs?

    The status of unionization of the TMM Project labor force would be determined by the work force itself later in the project development effort. TMM respects the strong union history in northern Minnesota. We are grateful for the public support many unions have expressed for our project and our industry.

  • HOW LONG-TERM ARE THE MINING JOBS?

    TMM is currently working to determine the duration of the mine plan it will formally propose for permitting. While the eventual mine plan duration may be limited to several decades, the Duluth Complex contains mineralization that can, through future exploration, permitting and operations, support jobs for generations.

  • How far in development and the regulatory process is the TMM Project?

    TMM is pursuing compact and efficient designs for the underground mine project, supported by site-specific environmental baseline studies. TMM expects to submit a formal proposal in the next 18 months. This action will initiate the extensive Environmental Impact Statement process. For more information, visit the Regulatory Process page.

  • Will there be opportunities to provide input?

    Yes. After TMM submits a formal proposal to the U.S. Bureau of Land Management, there will be a legally required environmental review process lasting several years. There are numerous opportunities for public input on what potential impacts the agencies should study throughout the Environmental Impact Statement process. For more information, visit the Regulatory Process page.

  • WILL THE TMM PROJECT BE SUBJECT TO ENVIRONMENTAL REGULATION AFTER IT’S PERMITTED?

    Yes. Today’s environmental regulations tightly control how mines are designed, operated and eventually closed. The Minnesota Department of Natural Resources, Minnesota Pollution Control Agency, U.S. Environmental Protection Agency, U.S. Army Corps of Engineers and other state and federal agencies will enforce regulations protecting water, soil, animals and air. Twin Metals Minnesota recognizes environmental conservation as a core value and is committed to protecting Minnesota’s wilderness, natural environment and recreational resources. For more information, visit the Responsible Mining page.

  • How will Twin Metals be held accountable for its activities?

    State and federal environmental laws, standards and regulations under which TMM would operate are some of the most stringent and comprehensive in the world. These rigorous standards not only guide the design and permitting of mining projects, but also hold companies accountable during operations and through closure of a mine. Twin Metals is dedicated to building and operating a mine project that utilizes industry best practices and meets all state and federal environmental standards. In addition, the Minnesota Department of Natural Resources, Minnesota Pollution Control Agency, U.S. Environmental Protection Agency, U.S. Army Corps of Engineers and other state and federal agencies will enforce regulations protecting water, soil, animals, air, and other natural resources.

    For example, during operations Twin Metals will have to collect frequent groundwater and surface water quality samples on a schedule established in our permits. The samples will be sent to a state-certified laboratory for water quality testing. Minnesota regulators will review the laboratory results to determine if they meet the stringent surface water and groundwater quality protection standards that will be specified in Twin Metals’ operating permits. Air quality permits will have similarly rigorous monitoring and reporting requirements.

    The water quality, air quality, wildlife, and wetlands environmental monitoring systems that will be required in permits will give these regulatory agencies real-time information about the environmental performance of all aspects of the Twin Metals project. The project environmental monitoring data will function as an early-notification system that will provide Twin Metals and Minnesota regulators with important and timely information about whether the project’s environmental protection systems are functioning as designed and in compliance with operating permits.

    If project monitoring data provide an early indication that the facilities may not be performing as designed, Twin Metals will immediately develop a plan to investigate. If this investigation confirms there is a problem, Twin Metals will take appropriate response measures to correct the situation under supervision from these agencies. Minnesota regulators oversee and enforce all of these steps.

    Minnesota regulators also have the authority to fine the company, and suspend or even revoke one or more of Twin Metals’ operating permit if the monitoring data reveal non-compliance with the environmental performance standards in our permits. As an extra safeguard, Minnesota regulators could use funds from bankruptcy-proof financial assurance that Twin Metals provides to respond to the problem.

  • How will taxpayers be protected?

    Minnesota’s mines are required by state law to have bankruptcy-proof financial assurance for reclamation and closure performance. Minnesota requires state-managed and annually adjusted financial assurance to cover any possible costs, including post-closure reclamation, before permits can be issued. Minnesota is authorized to deny or revoke a permit if a company does not comply.

  • How will the TMM Project protect the Boundary Waters Canoe Area Wilderness?

    State and federal environmental requirements, including those protecting the BWCAW, must be met or exceeded, or the TMM Project will not be authorized to move forward. Specific aspects of the project are still under study, but we do know the project is based on an underground mine plan targeting the Maturi deposit, which is located outside the Boundary Waters Canoe Area Wilderness and long-established state and federal protective buffer zones. Additionally, testing shows the tailings would be non-acid generating. Extensive additional testing will be conducted under the supervision of the Minnesota Department of Natural Resources and federal agencies.

    Once a formal project is proposed, the TMM Project must complete the rigorous Environmental Impact Statement (EIS) process. The formal proposal will detail specific environmental protection measures incorporated in the design and operations plans. The EIS process uses these detailed project plans and site-specific environmental data and in its analysis.

    TMM must also demonstrate ongoing compliance with standards throughout the life span of the project. For example, during operations Twin Metals will have to collect frequent groundwater and surface water quality samples on a schedule established in our permits. The samples will be sent to a state-certified laboratory for water quality testing. Minnesota regulators will review the laboratory results to determine if they meet the stringent surface water and groundwater quality protection standards that will be specified in Twin Metals’ operating permits. Air quality permits will have similarly rigorous monitoring and reporting requirements.

    The water quality, air quality, wildlife, and wetlands environmental monitoring systems that will be required in permits will give these regulatory agencies real-time information about the environmental performance of all aspects of the Twin Metals project. The project environmental monitoring data will function as an early-notification system that will provide Twin Metals and Minnesota regulators with important and timely information about whether the project’s environmental protection systems are functioning as designed and in compliance with operating permits.

    If project monitoring data provide an early indication that the facilities may not be performing as designed, Twin Metals will immediately develop a plan to investigate. If this investigation confirms there is a problem, Twin Metals will take appropriate response measures to correct the situation under supervision from these agencies. Minnesota regulators oversee and enforce all of these steps.

  • HOW WILL THE MINE MINIMIZE THE IMPACT OF ITS ACTIVITY?

    Twin Metals’ will minimize the impact of mining activity by using underground mining operations coupled with storing approximately half of the tailings as permanent cemented backfill in the underground mine. The remaining tailings would be stored on a modern, lined surface tailings storage facility near the Peter Mitchell Mine southwest of the city of Babbitt, Minnesota, and outside the Rainy River Watershed. Extensive additional testing will be conducted under the supervision of the Minnesota Department of Natural Resources and federal agencies. As the result of the EIS process, the regulatory agencies may impose additional measures to reduce potential impact.

    During operations Twin Metals will have to collect frequent groundwater and surface water quality samples on a schedule established in our permits. The samples will be sent to a state-certified laboratory for water quality testing. Minnesota regulators will review the laboratory results to determine if they meet the stringent surface water and groundwater quality protection standards that will be specified in Twin Metals’ operating permits. Air quality permits will have similarly rigorous monitoring and reporting requirements.

    The water quality, air quality, wildlife, and wetlands environmental monitoring systems that will be required in permits will give these regulatory agencies real-time information about the environmental performance of all aspects of the Twin Metals project. The project environmental monitoring data will function as an early-notification system that will provide Twin Metals and Minnesota regulators with important and timely information about whether the project’s environmental protection systems are functioning as designed and in compliance with operating permits.

    If project monitoring data provide an early indication that the facilities may not be performing as designed, Twin Metals will immediately develop a plan to investigate. If this investigation confirms there is a problem, Twin Metals will take appropriate response measures to correct the situation under supervision from these agencies. Minnesota regulators oversee and enforce all of these steps.

  • What do terms like “waste rock” and “tailings” mean?

  • What type of tailings facility is TMM planning?

    TMM has thoroughly studied multiple tailings deposition methods including dry stack, and we plan to propose a conventional style of tailings deposition. While dry stack can provide advantages in certain situations, there are technical implementation issues that the industry has yet to solve with using the method in climates like Minnesota’s and at our anticipated production rate.

  • Are there similar projects to the TMM Project about which I can learn?

    One example is the Eagle Mine, located in western Marquette County, Michigan, an underground copper-nickel mine and currently the only mine producing nickel in the U.S. The mine began production in September 2014 after becoming the first mine to become permitted to mine nonferrous minerals in the state in 2007.

  • WHO CAN I CONTACT TO LEARN MORE ABOUT THE PROJECT?