Nucor Steel-Arkansas v. Big River Steel, LLC

GRUENDER, Circuit Judge.

Nucor Steel-Akansas and Nucor Yama-to Steel Company (collectively, “Nucor”) are sister entities that operate two steel mills near Blytheville in Mississippi County, Arkansas. Big River Steel (“Big River”), a Nucor competitor, has received a permit from the Arkansas Department of Environmental Quality (“ADEQ”) to construct a new steel recycling and manufacturing facility in Osceola, Arkansas. Nucor brought a citizen suit in the district court for the Eastern District of Arkansas under the Clean Air Act (“CAA”), seeking injunc-tive relief to stop Big River from…