South Carolina Gov. Henry McMaster, Nucor chief executive John Ferriola and many others traveled to Nucor’s Darlington, S.C., bar mill for a ceremony Wednesday. During the event, they recalled the significance of the plant’s first melt, which took place June 26, 1969.
  
“Nucor founder Ken Iverson decided to build a mill that used an electric arc furnace to melt scrap metal into new steel products instead of making steel using a blast furnace – the dominant method of steelmaking in the United States at that time," Nucor said in a statement. "That decision revolutionized the way steel is made in America. Today, EAFs account for approximately 70 percent of the steel produced in this country,” the company said. 

Ferriola said the pour didn’t go as planned -- steel broke out of the vessel and hot metal poured on to the caster, basically melting it. 

“Untested workers more used to working in the fields than a steel mill panicked and ran from the building, convinced that the furnace was going to explode,” he said. “But they soon returned, and went right to work figuring out what went wrong. It wasn’t long before Nucor was making steel bar for its Vulcraft operations. And from that point forward, Nucor kept innovating and finding new ways to make steel,” Ferriola said. 

You can find more coverage of the event here.