HARRISBURG, Pa. (AP) — The fatal explosion last week at U.S. Steel’s Pittsburgh-area coal-processing plant has revived debate about its future just as the iconic American company was emerging from a long period of uncertainty.

Brian Doyle remembers the explosion that hurled him to the coke plant’s floor — but little else from that day. It was a Wednesday — July 14, 2010 — and Doyle, a steamfitters union member and contractor for Power Piping,