The Minnesota Pollution Control Agency and the U. S. Environmental Protection Agency said Thursday that they have reached a settlement with Mesabi Nugget Delaware, LLC for state and federal air-quality permit violations at the company’s idled plant near Aurora.

Mesabi Nugget will pay a $150,000 penalty for alleged air emissions violations for particulate matter (dust), mercury, volatile organic compounds, nitrogen oxide and carbon monoxide.

In addition to paying the fine the company will also make changes to their operations if they ever reopen.

Mesabi Nugget, which opened in late 2009, closed in January, 2015. It is 81 percent owned by Steel Dynamics and 19 percent owned by Japan-based Kobe Steel. The unique plant, the first of its kind in Minnesota, turns iron ore concentrate recovered from old mine sites directly into 97 percent pure iron nuggets used to enhance scrap metal in electric arc “mini-mill” steel mills.

Steel Dynamics has made no announcement of the plant reopening.