About Us | CMC Steel | Commercial Metals Company- rolling mills clunt ,CMC Steel's mini and micro mills are strategically located throughout the U.S. As the domestic steelmaking segment of Commercial Metals Company, we operate three EAF mini mills and two EAF micro mills, as well as a rerolling mill.Ohio's Old Mills by CountyOhio's old mills are fulfilling many of these alternative uses today. The Mill's Role in the Community The mill sites in the early 1800's were established to serve local farmers.