Nucor Corp. has announced plans to invest $45 million at its Darlington, S.C., steel mill over the next five years. The endeavor calls for capital improvements to the existing facility and will not result in more jobs being created. The project will include upgrading equipment in the rolling mills and improvements to the scrap conveyor, alloy-handling systems, ductwork and cranes. The Darlington mill produces concrete reinforcing bars, hot-rolled bars, rod, light shapes, structural angles and channels utilizing 100% recycled steel. These products serve industries such as automotive, construction, energy and others.