Northshore Mining operates the Peter Mitchell Mine, a taconite ore mining operation, in Babbitt. It sends the ore that it mines there via rail to a processing plant in Silver Bay, which is a separate facility with its own permits.
Our role
The MPCA is responsible for issuing and enforcing permits that limit emissions from Northshore Mining’s operations to protect the environment and health of Minnesotans. Those permits reflect current state laws and regulations.
Northshore submitted an application for a reissued air permit in 2009. The MPCA has drafted a reissued air permit and made it available for public comment.
Project information
Northshore operates mining equipment, haul trucks, a primary ore crusher, material loadout and stockpile operations, and combustion sources for maintenance and heat at the Peter Mitchell Mine. Pollutants of concern from this facility include particulates from the primary ore crusher, which are controlled by a fabric filter, and products from combustion such as nitrogen oxides and carbon monoxide. Wind and human activity at the facility also produce airborne particulate matter known as fugitive dust, which comes from sources such as blasting, haul trucks, and material stockpiles.
The draft reissued air permit does not authorize any construction or new emissions. The draft air permit limits particulate matter emissions and requires testing for particulate matter.
Key changes and updates in the draft air permit include:
- the addition of blasting and contractor activities as sources of fugitive dust and gases
- restrictions to burn only propane and natural gas in the facility’s shop boilers
- compliance monitoring requirements for the fabric filter controlling the ore crusher's emissions
- requirements for Northshore to submit a modeling protocol and modeling results for fine particulate matter
Next steps and timeline
The MPCA is currently considering comments on the draft reissued air permit from a public notice period that closed Dec. 16, 2024.