State pollution regulators and the owner of a scrap yard in north Minneapolis have reached an agreement that requires that a five-story riverside metal shredder there be tested to see if it's meeting state-set limits for emitting particles into the air.

The deal, subject to court approval, should provide more information on the shredder's significance in air-quality violations detected by Minnesota Pollution Control Agency (MPCA) monitoring stations that bracket the scrap yard just south of the Lowry Avenue Bridge.

"Everyone wins by finding out what are the emissions from this facility, and one side or the other is going to be proven right or wrong," said Jack Perry, an attorney representing shredder operator Northern Metal, which recycles metal.

Northern Metal had sued in Ramsey County District Court to block the state monitoring. When the state ordered testing of the machine's emissions and pollution controls, the firm asked a judge to block that. They've been negotiating since.

The dispute involves a shredder that's been controversial since a predecessor owner of the yard sought a city permit for a shredder known as a Kondirator in 1988. That machine achieved notoriety because of its name, but a shredder made by a different manufacturer was later installed.

That machine started operating in 2009 after a lengthy battle that was fought at City Hall, the courts and the Legislature about whether the machine should even be installed and what limits should be placed on its operation and emissions. The shredder failed to meet environmental standards set in its initial permit. In response, the MPCA relaxed the permit without further environmental studies sought by three legislators, some area residents and environmental advocates.

The new settlement requires the company to hire an independent consultant to review the system that funnels air inside the building toward three types of pollution controls as well as the controls themselves, plus the issue of dust arising from the outdoor scrap yard. That report is due Jan. 15.

After time to make any necessary changes, Northern Metal is required to test the plant's emissions of particles to see if they meet a permit standard of fewer than 2 pounds per hour. It also needs to show that all of the emissions leaving the plant are routed through pollution controls. If the plant fails to meet required standards, another test will be run. A second failure would mean the company would be required to seek a revised permit.

Perry said the Northern Metal still plans to find a new site with rail access for the shredder northwest of the metro area. The firm said it expects any new site to take three years to start operating. It hopes the new site will have looser air-quality restrictions than the Minneapolis site.

The shredder produces particles of dust as it bashes pieces of metal into smaller chunks that can be sold for a higher price in downriver mills.

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