A large aluminum recycling operation in Rosemount faces more than $1 million in fines, civil penalties and required plant upgrades for violating clean air laws and trying to conceal it.

Spectro Alloys Corp. pleaded guilty Thursday, June 7, in U.S. District Court in Minneapolis and was fined $500,000. A pending civil enforcement agreement would cost it another $600,000 and require installation of new pollution-control equipment.

The separate cases address emissions violations at its plant near the Mississippi River going back to 2003, false company statements to federal and state regulators, and inadequate equipment and operating procedures.

Asked for a comment, Spectro, which says it operates the Midwest's largest scrap aluminum recycling plant, instead released a statement.

After saying it admitted to two allegations of failing to report one air quality engineering test in 2006, it added: "Spectro acknowledges that the test should have been reported and is sorry for the mistake.... In addition, Spectro settled other (Environmental Protection Agency) issues from 2003 to 2009. All such issues were corrected and individuals responsible for those lapses are no longer with the company.''

The U.S. Attorney's Office said Spectro pleaded guilty to two counts of violating the federal false statements statute.