The air quality monitors near the Northern Metal scrap yard in Minneapolis continue to record particle levels that exceed state standards, even as a legal showdown between the state and the company has been pushed off another five weeks.

The company and the Minnesota Pollution Control Agency were scheduled to meet in court last Friday over the company's contention that pollution regulators are picking on the scrap yard.

But that was delayed to Oct. 5 because the parties agreed to a court suggestion that their arguments be consolidated, attorney Jack Perry said.

The monitors near the company have logged an additional four instances where either the human health standard or the state environmental standard were exceeded for the total number of microscopic particles in the air. The monitors are located across the street from the north and south ends of the riverfront yard.

The most recent violation was recorded on Aug. 10, according to the agency's website.

All four instances come in addition to multiple violations the agency alleged in July were caused or contributed to by the company. The state allegations came in responding to a company request that a court block the environmental monitoring, which it alleged exceeded the state's authority.

The state asked Ramsey County District Court to bar the company from further violations, even if that means reducing or ending operations, and to order the firm to pay fines associated with the violations.

The dispute is the latest chapter in the city's longest-running environmental battle. The company applied for a permit to install a metal shredder in 1989 in a bid to increase the market value of scrap metal it recycles. After a long fight that reached the courts and the Legislature, the company prevailed and the firm began running it in 2009. But it soon fell out of compliance with state air standards, which led the agency to loosen its permit limits in 2012.

The state said at the time that it expected the shredder to contribute only a small part of the area's pollutants.

The MPCA then installed monitors at the start of 2013. Although the area met the standard for the most dangerous and smallest particles, there have been repeated violations since for the total number of particles collected by monitors.

Steve Brandt • 612-673-4438

Twitter: @brandtstrib