Every time it happens it seems a bit like the beginning of doomsday. And it happened again at 6 p.m. last Sunday: an alarm shrilled, lights flashed in the control room. A monitor was signaling that the water cooling the plutonium- producing N reactor at Hanford, Wash., had dropped below acceptable levels. Shutdown!
Just a few hours after the Hanford reactor turned itself off last week, the authorities knew there had been a false alarm. "It was a faulty monitor," said Steven Irish, a spokesman for U.N.C. Nuclear Industries, which operates the reactor. "There wasn't a low-flow problem." And so, on...