MINNEAPOLIMEDIA NEWS | Minnesota Regulators Seek to Revoke St. Paul Foundry’s Air Permit After Years of Compliance Disputes

ST. PAUL, MN (July 21, 2026)  A long-running dispute over emissions from Northern Iron has moved into a contested legal proceeding as Minnesota regulators seek to revoke the St. Paul foundry’s air-quality permit.

Northern Iron operates in the Payne-Phalen neighborhood and manufactures metal castings and machine components.

The Minnesota Pollution Control Agency says the company repeatedly failed to provide information necessary to evaluate emissions, determine compliance and write a protective operating permit.

Northern Iron requested a contested-case hearing after the MPCA formally began the revocation process in June 2025.

Regulators Cite Missing Information

The MPCA says Northern Iron failed to provide complete building-capture data showing whether emissions are contained and directed through pollution-control equipment.

Regulators have also raised concerns about stack testing, lead-detection limits, hood evaluations and the company’s compliance with a 2023 agreement and subsequent agency orders.

Before initiating revocation, the MPCA gave the company a final deadline to provide the requested material. The agency said information submitted by Northern Iron remained incomplete.

Minnesota law requires regulators to determine that a permit holder can achieve and maintain compliance before issuing or renewing a permit.

Northern Iron disputes the agency’s attempt to revoke the permit and is entitled to challenge the allegations through the contested-case process.

Neighborhood Health Concerns

The foundry’s location in a residential section of St. Paul has intensified community concern.

Air emissions do not stop at a facility’s property line. Residents have asked whether pollution from the plant could affect nearby homes, schools, parks and people with respiratory or cardiovascular conditions.

The MPCA installed an additional monitor near Northern Iron in April 2025 to test for dozens of volatile organic compounds and carbonyls.

Permit revocation would represent one of the agency’s strongest enforcement options. The proceeding will determine whether Northern Iron may continue operating under its existing authorization, must satisfy additional requirements or loses its permit.

Until that process is complete, allegations from regulators and responses from the company remain subject to administrative and judicial review.

Residents can subscribe to MPCA updates or email questions to northern.iron@state.mn.us.

Sources: MPR News and Minnesota Pollution Control Agency

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