DNR – State receives revised Dam Safety permit applications and a new Public Waters Work permit application

minnesota department of natural resources

PolyMet Permitting Update

May 16, 2017

DNR – State receives revised Dam Safety permit applications and a new Public Waters Work permit application

PolyMet proposed plant site

Dam Safety Permit

Poly Met Mining, Inc. (PolyMet) has submitted two revised Dam Safety Permit applications to the DNR. One application addresses the Flotation Tailings Basin and the second application is for the Hydrometallurgical Residue Facility for the proposed NorthMet Project.  These revised applications include changes made by PolyMet based on initial feedback provided by DNR technical experts and external consultant Emmons Olivier Resources, Inc. (EOR).

PolyMet’s revised Dam Safety Permit applications, dated May 15, 2017, have been sent out for review by technical experts from other units of government having jurisdiction in such matters, as required by MN Rule 6115.0250.  The DNR has also sent the revised permit applications to the Bois Forte Band of Chippewa, the Grand Portage Band of Lake Superior Chippewa, and the Fond du Lac Band of Lake Superior Chippewa for review. Following a 30-day review period, the DNR will consider input received from these governmental entities and determine whether to proceed with preparing draft Dam Safety Permits. This review is not the public input stage of the process. At a future date, the DNR will seek public review and input on draft permit decisions. 

In addition, PolyMet has submitted the following documents to support review of the Dam Safety permit applications:

  • Updated Flotation Tailings Basin Instrumentation and Monitoring Plan 
  • Updated Flotation Tailings Basin Contingency Action Plan
  • A new Flotation Tailings Basin Template Pilot Test Plan for Bentonite Amendment of Tailings

Dam Safety Geo-technical Report

The DNR has also received a dam safety geo-technical report on PolyMet’s proposed NorthMet Project to supplement the permit application review process. The DNR requested that a team of top geo-technical dam safety experts be assembled to assess the proposed design, operation and maintenance of the NorthMet facilities. The team was led by the State’s consultant EOR and included experts with both Minnesota and worldwide experience. The group included a member of the review panel that previously investigated the Mt. Polley dam failure in British Columbia. 

Public Waters Work Permit

PolyMet has submitted a Public Waters Work Permit application to the DNR.  The application is for a culvert extension to initiate the widening of the Dunka Road for the proposed NorthMet Project. DNR technical experts are currently initiating their review of this application and will then seek input from local governmental units and tribal governments on the application. 

More Information

All GovDelivery messages, as well as additional documents, reports, and applications received to date are available on the State’s PolyMet Portal (click on the DNR link).

State's PolyMet Portal Website