PolyMet's NorthMet Mining Project

PolyMet's proposed plant site

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Poly Met Mining, Corp. (PolyMet) is proposing a mine and associated processing facilities for the extraction of copper, nickel, and platinum group elements (PGE) in northeastern Minnesota. The mine would be the first of its kind in the state.

The Minnesota DNR's review of PolyMet's NorthMet proposal has followed a rigorous environmental review process and extensive evaluation of the company's permit applications, beginning in 2005. This included careful review of more than 22,000 public comments on draft permits in 2017 and early 2018.


March 2023

Following a number of court decisions that upheld most of the conclusions made by DNR throughout the review process, the Minnesota Supreme Court only directed the DNR to add a fixed term (set in years) to the permit to mine and to hold a contested case hearing on whether using bentonite clay to reduce oxygen and water infiltration into the proposed tailings basin is a practical and workable reclamation technique. The contested case hearing is set for March 27. Following the hearing and after review of the recommendation of the administrative law judge, the DNR will make a final permit decision on the permit to mine application.

DNR notice of hearing »

DNR GovDelivery bulletin on notice of hearing »

April 2021

On April 28, 2021, the Minnesota Supreme Court issued its ruling on the Court of Appeals decision regarding the permit to mine issued to PolyMet in November 2018. The Court offered a clarifying interpretation of who has standing to request a contested case hearing, but concurred with the DNR's application of the standards for granting a contested case hearing. The Court found ample evidence in the permit records to support the DNR's decisions on the critical issues of dam safety and tailings basin closure and found that DNR did not need to hold a contested case hearing on financial assurance or whether Glencore was required to be on the permit to mine at the time of permit issuance. The Court instructed DNR to establish a fixed term for the permit to mine and to hold a contested case hearing on whether the use of bentonite is a practicable and workable technology to reduce oxygen infiltration into the project tailings.

Minnesota Supreme Court Ruling »

February 2020

On February 12, 2020, the DNR submitted a petition to the Minnesota Supreme Court seeking review of the Minnesota Court of Appeals' January 13, 2020 decision regarding three DNR-issued permits for PolyMet's NorthMet project.

Petition for review » 
Addendum to petition for review »

This addendum contains the NorthMet project Permit to Mine Findings of Fact, originally posted November 2018.

August 2019

On August 7, 2019, the DNR issued the following order regarding requests for reconsideration of the Dam Safety Permit 2016-1380 and the nonferrous Permit to Mine.

Order of Commissioner » 
Dam Safety Memo »

The DNR has issued PolyMet's Permit to Mine, Wetland Replacement Plan, Water Appropriation, Dam Safety, Endangered Species Taking Permit, and Public Waters Work permits. You can find these permits, along with supporting documentation, using the navigation menu above or below.

Permit to Mine » 
Water Appropriation Permit » 
Dam Safety Permit » 
Other DNR Permits »

Environmental review process

Prior to the current permitting phase, the proposed NorthMet Mining Project went through an extensive environmental review process. PolyMet submitted its initial project proposal to the DNR in February 2005. In accordance with state and federal laws, an Environmental Impact Statement (EIS) was prepared under the leadership of the DNR, U.S. Army Corps of Engineers (USACE), and the U.S. Forest Service (USFS). The Final EIS was deemed adequate by the DNR in March 2016 marking the end of the state's environmental review process. On January 9, 2017, the USFS signed the Final Record of Decision authorizing a land exchange with PolyMet. This exchange will transfer the surface property owned by the Forest Service to PolyMet, who controls the sub-surface (mineral) rights. The land exchange is presently being challenged in federal lawsuits. On March 21, 2019, the USACE completed its Record of Decision and issued an individual permit to PolyMet for its NorthMet project.

Environmental review webpage »

Project location

The NorthMet Mining Project will be located in the St. Louis River watershed on the eastern edge of the Mesabi Iron Range, about 6 miles south of Babbitt.

map of sites

Partner links

Minnesota Pollution Control Agency » 
U.S. Forest Service (USFS) » 
U.S. Army Corps of Engineers (USACE) »


DNR text messaging changes – sending number change
DNR Initiates Contested Case Hearing Process Regarding PolyMet Permit to Mine
DNR – PolyMet Annual Report
MPCA – Quarterly PolyMet Update – 4th Quarter 2018
DNR – Quarterly PolyMet Permitting Update – 4th Quarter 2018
MPCA issues air and water permits
DNR issues permits for NorthMet mining project in northeast Minnesota
MPCA sends PolyMet revised permit documents for EPA review
DNR – Quarterly PolyMet Permitting Update – 3rd Quarter 2018
DNR – DNR receives revised application from PolyMet for a permit to take endangered and threatened species
DNR – Quarterly PolyMet Permitting Update – 2nd Quarter 2018
MPCA Quarterly update
MPCA quarterly update
DNR - Quarterly PolyMet Permitting Update – 1st Quarter 2018
DNR - Deadline to Submit Written Responses to Petitions for Contested Case Hearings on the draft PolyMet Permit to Mine is April 6, 2018
MPCA – PolyMet draft permits available for comment
Aurora and Duluth meetings provide opportunities for public comment on recently released draft PolyMet permits
DNR - Petition deadline for contested case hearing is February 28, 2018, for draft PolyMet Permit to Mine
MPCA -- PolyMet Public Meetings
DNR – State Announces Notice of Draft Permit to Mine for PolyMet NorthMet Project
DNR – State Receives Revised Permit to Mine Application from PolyMet
DNR – Quarterly PolyMet Permitting Update - 3rd Quarter 2017
MPCA – Quarterly PolyMet permitting update
DNR’s Public Comment Opportunity on Draft PolyMet Dam Safety and Public Waters Work Remains Open Through October 16, 2017
DNR Opens 30-day Public Comment Opportunity on Draft PolyMet Dam Safety and Public Waters Work Permits
DNR opens public comment period on draft PolyMet water appropriation permits
MPCA - Quarterly PolyMet permitting update
DNR – Quarterly PolyMet Permitting Update
DNR – State Requests Review of PolyMet’s Public Waters Work permit application
DNR – State receives revised Dam Safety permit applications and a new Public Waters Work permit application
MPCA - Quarterly PolyMet permitting update
DNR – Quarterly PolyMet Permitting Update
DNR – State Receives Updated Water Appropriation Permit Application from PolyMet
DNR - Quarterly PolyMet permitting update
MPCA – Quarterly PolyMet permitting update
DNR – State Receives Permit to Mine Application and Financial Assurance Proposals from PolyMet
MPCA: PolyMet submits application for air permit to MPCA
MPCA: PolyMet submits a 401 certification request for NorthMet project
MPCA: PolyMet submits NPDES/SDS water quality application for NorthMet project
DNR – State Receives Dam Safety and Water Appropriation Permit Applications from PolyMet
DNR-Reminder to Sign Up for PolyMet NorthMet Project Updates
DNR – PolyMet Informational Meeting Sign Policy and Information Available
DNR – State Launches PolyMet Permitting Portal
DNR selects financial assurance contractor to assist in review of potential PolyMet permit application
DNR to host public information meeting in advance of PolyMet permit application

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