Hibbing Taconite has been fined more than $15,000 for air pollution violations at its giant production facility near Hibbing.
Hibbing Taconite mines iron ore, and uses three huge natural gas furnaces to process it into pellets used in steelmaking. In January the facility failed a performance test for particulate emissions, but passed a re-test the following month.
The company's pollution control devices known as wet scrubbers exceeded their allowable operating ranges for pressure drop and water flow, which help ensure the equipment is working properly.
In 2008 the company paid a $24,000 fine for a very similar failure.
"In the overall scheme of air quality violations, the MPCA has definitely assessed much larger penalties and also much smaller," said Katie Koelfgen of the Minnesota Pollution Control Agency. "This facility has had similar violations in the past, and that was taken into account when calculating the penalty."
Hibbing Taconite has not yet responded to a request for comment. The company was just issued a new air emission permit last year.