A judge has ordered the Minnesota Pollution Control Agency to shut down two air monitors near property owned by the Northern Metal scrap yard in north Minneapolis or explain their need for the air quality testers by July 27.

Ramsey County District Judge John Guthmann issued his order last Thursday in an action brought by Northern Metal Recycling, which alleges that it is unfairly being singled out by the agency as it investigates five instances in which an area monitor recorded air particles that exceeded the allowable standard.

The agency said Monday in a statement that it "has no intention of shutting the monitors down and intends to prove to the court that it has the authority and responsibility to monitor air quality, and we believe that Northern Metal's argument has no legal merit."

Assistant Commissioner David Thornton went further. "They're just wrong," he said of the company.

Northern Metal President Stephen Ettinger wrote, "Unfortunately, I felt the need to petition the court to compel the MPCA to follow their own rules, for the second time in the past four years or so."

Rep. Joe Mullery, DFL-Minneapolis, criticized the company: "Amazingly, they are trying to prevent an agency which exists to protect the public from pollution from actually doing its job."

Northern Metal owns the former American Iron yard on the west bank of the Mississippi River, just south of the Lowry Avenue Bridge. The company and some area residents have been battling for about 20 years over installation and operation of a metal shredder that pulverizes scrap. The machine operates inside a building and the company uses several techniques to capture potentially harmful particles generated by the machine.

The agency's prior modeling for its air permit estimated that the shredder would release 3.5 tons of particles annually, but the firm said that represented a minuscule amount of particles in the industrialized area.

The firm's court filings allege that the agency didn't follow state and federal procedures regarding the location of its monitoring stations.

The agency has said little publicly about its investigation into the particle violations, saying state law precludes it from doing so until its investigation was completed. It didn't disclose the addition of a second monitor until Monday, 11 days after the firm said it was informed.

The agency in 2012 modified the company's emissions permit, which the company was violating, according to a test conducted soon after the shredder began operating in 2009. The state rejected the need for further environmental studies sought by local lawmakers after concluding that the shredder would increase the area's concentration of more dangerous small particles by 2 percent. It installed the monitor shortly after, but the violations haven't involved the small-particle standard but rather those for total particles.

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