On St. Paul’s East Side, a century-old iron foundry is caught in a high-stakes fight over its future. State regulators have moved to pull Northern Iron’s air permit after modeling and testing suggested the plant may be sending dangerous levels of lead and fine particulate pollution into nearby neighborhoods. The company insists it is closely tracking air quality and says monitoring so far shows it is in compliance while the dispute winds through the courts.
Regulators Launch Permit Revocation Push
According to the Minnesota Pollution Control Agency, the state gave Northern Iron a final deadline to turn over required building-capture data, stack tests and hood certifications, and then found the company’s May 8, 2025 submission came up short. The agency says Northern Iron has repeatedly failed to meet regulator expectations and that its continued refusal to provide information is enough to justify starting the permit revocation process. MPCA officials describe revocation as a last resort but say it is necessary to protect human health if the foundry cannot demonstrate that it will meet air-quality standards.
Courtroom Showdown
At a hearing last week, Northern Iron asked an administrative law judge to rule on the permit dispute without holding a full evidentiary hearing. The judge has taken that motion under advisement, and the foundry is allowed to keep operating while the legal fight plays out. Dozens of residents and community leaders packed the session and urged the court to back the state’s effort to strip the air permit. MPR News reported on the turnout and the arguments in front of the administrative judge.
Modeling, Monitors And Past Violations
New air-emission modeling the agency received in February 2024 indicated Northern Iron’s lead and particulate pollution was highly likely to exceed the National Ambient Air Quality Standards, according to the Minnesota Pollution Control Agency. Inspectors also found unauthorized equipment changes in 2020 that increased particulate emissions, and in 2023 the agency hit the company with a $41,500 enforcement penalty tied to air-permit violations. In response, MPCA staff have installed monitors near the foundry and ordered revised modeling and additional controls to show the plant can meet state and federal standards.
Neighbors File Suit
Residents living within a half-mile of the foundry filed a class-action complaint in March 2025, alleging soot, dust and heavy metals from Northern Iron have damaged property values and invaded their homes. The civil case names the foundry’s owners and seeks unspecified damages and equitable relief to halt the alleged pollution. Coverage of the lawsuit also noted the plant employs roughly 80 local workers, underscoring the economic tension in the neighborhood, as reported by the Pioneer Press.
Foundry Response And Jobs Concern
Northern Iron says it is committed to being a responsible and transparent neighbor and points to monitoring data that, the company argues, show compliance with Minnesota and national air standards. The owners say they are installing pollution-control equipment and working with regulators to resolve the permit questions rather than walk away from the East Side jobs. The company’s public statements and monitoring updates are posted on Northern Iron.
What Comes Next
The administrative law judge must now decide whether to grant the company’s request to skip a full evidentiary hearing. If that motion is denied, the Minnesota Pollution Control Agency’s case will move to a full hearing currently scheduled for late October, according to the Pioneer Press. A permit revocation, if ultimately upheld, could impose strict operating limits or even force a temporary shutdown while new pollution controls are installed, and the separate class-action lawsuit would continue in Ramsey County civil court. Regulators say their priority is protecting human health, even as they weigh the potential hit to local manufacturing jobs.
