northmet project


We are located in northeastern Minnesota near the community of Hoyt Lakes, within the established Mesabi Iron Range mining district. The project is located south of the Laurentian Divide in the St. Louis River basin, 175 river miles upstream from Lake Superior. The Laurentian Divide separates the St. Louis River basin from the Rainy River basin, where the Boundary Waters Canoe Area Wilderness is located.

Ownership and control

Our project features two significant assets: the deposit itself, and the former LTV Steel processing facilities and infrastructure, which we will repurpose. We control 100 percent of the NorthMet ore body through perpetually renewable leases with private mineral owners. We have total surface rights, including ownership and other use and occupancy rights, to approximately 19,000 acres (nearly 30 square miles) of land including the mine and processing sites, the transportation corridor connecting those sites, the existing tailings basin and buffer.

Land Exchange

The U.S. Forest Service completed a land exchange with PolyMet June 28, 2018, consolidating our respective land ownerships. The Forest Service acquired 6,690 acres of private land from PolyMet to become part of the Superior National Forest; we acquired 6,650 acres of surface land over the mineral deposit we already control. For more details about the land exchange, download our land exchange booklet.


We will develop the mine in two distinct phases. Phase I involves development of 225 million tons – nearly one-third of NorthMet’s known resource – into an operating mine processing 32,000 tons of ore per day. It also includes rehabilitating the former LTV Steel Mining Company processing plant.

Phase II involves construction and operation of a hydrometallurgical plant to treat nickel sulfide concentrates into upgraded nickel-cobalt hydroxide and recover additional copper and platinum-group metals. While development of Phase II will be at the company’s discretion, both phases are currently being permitted and are included in the Final Environmental Impact Statement and draft permits.

At peak production (Phase I and II) we will annually produce approximately 69.4 million pounds of copper, 9.6 million pounds of nickel, 352,000 pounds of cobalt and 166,000 troy ounces of precious metals in concentrate – essential metals for our modern lifestyles and national security. See more details on production in the Technical Report (PDF).

Environmental commitment

Our mine and processing facilities are designed to comply with all applicable state and federal standards to protect Minnesota’s water, air and other natural resources. These are some of the strictest standards in the country. We also will clean up legacy water issues left from former taconite mining and processing operations on the property. A comprehensive 10-year environmental review of the project completed by state and federal regulatory agencies demonstrates that the project is capable of meeting standards.

For more details about how we will protect Minnesota’s water, download our water quality fact sheet. You can also read a summary of the environmental review and permitting highlights.

Mining method

Our project will be mined by open pit methods to a depth of approximately 700 feet below surface. Read more details on the mining and processing method.

Processing method

Ore from the mine will be transported approximately 8 miles west by rail to existing facilities formerly held by LTV Steel Mining Company, which we own and will modernize. We will use existing crushing facilities combined with new milling and flotation circuits to produce copper and nickel concentrates that will be shipped via the existing railhead.

Read more details on the mining and processing method.

NorthMet ore body

The NorthMet deposit, located in the Partridge River Intrusion of the Duluth Complex, is a large, near-surface, disseminated deposit containing copper, nickel, cobalt, platinum, palladium, gold and silver. The ore body comprises 254.7 million tons of Proven and Probable reserves grading 0.294 percent copper and 0.084 percent nickel. Measured and Indicated Mineral Resources of 649.3 million tons grading 0.245 percent copper and 0.07 percent nickel and 508.9 million tons of Inferred material at .240 percent copper and .070 percent nickel. [Please refer to the Technical Report (PDF) for assumptions and explanations; see “Cautionary note to U.S. investors” regarding disclosure on Measured and Indicated Mineral Resources.]


Our project will employ 360 workers directly, create more than 600 indirect jobs and generate an estimated $515 million annually for St. Louis County according to an independent study (PDF) by the University of Minnesota Duluth Labovitz School of Business and Economics.

Capital costs for Phase I are estimated at $945 million and include refurbishment of the exiting primary crushing circuit and replacing the existing rod and ball mill circuits with a new, modern semi-autogenous grinding (SAG) mill, ball mill and flotation circuit. It also includes rail upgrades, purchasing heavy mining equipment and a state-of-the-art wastewater treatment plant.

More than $300 million already has been invested in the project, a large share of that for environmental review and permitting. We also must provide bankruptcy-proof financial assurance, the provisions of which are in the Draft Permit to Mine.

We issued an updated Technical Report including updated capital and operating costs, and project economics, on March 26, 2018.


The project will require about 18-24 months for construction and ramp up to full production once permits are in hand. It will require an estimated two million construction hours – about the same number of hours required to build Target Field, home of the Minnesota Twins Major League Baseball team.


We enjoy tremendous local support for the project, receiving resolutions of support from more than 30 local city, county and other government and business institutions. We also have the support of Jobs for Minnesotans, a partnership of statewide business and labor groups formed to advance copper-nickel mining in Minnesota. We are sincerely grateful for the encouragement and support we receive from our local communities. See who has officially endorsed the project.


Download our project brief for a broad overview of PolyMet’s NorthMet Project.