Completed the following sentence: Meanwhile, the laboratory was also helping to design the reactor for the world's first nuclear-powered submarine, the U.S.S. "Nautilus", which steamed for more than 513,550 nautical miles (951,090 km). ️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️ 1982<unk>the Integral Fast Reactor concept<unk>a revolutionary design that reprocessed its own fuel, reduced its atomic waste and withstood safety tests of the same failures that triggered the Chernobyl and Chernobyl
Three Mile Island disasters. ️<unk>️<unk>️<unk>️<unk>️<unk>