These heavier-than-uranium, or "transuranic," elements do not produce nearly the amount of heat or penetrating radiation that fission products do, but they take much longer to decay. These atoms form heavier elements such as plutonium. Second, some uranium atoms capture neutrons produced during fission. These isotopes, called "fission products," account for most of the heat and penetrating radiation in high-level waste. The fission creates radioactive isotopes of lighter elements such as cesium-137 and strontium-90. First, uranium atoms split, creating energy that is used to produce electricity. Before these fuel rods are used, they are only slightly radioactive and may be handled without special shielding.ĭuring the fission process, two things happen to the uranium in the fuel. Nuclear reactor fuel contains ceramic pellets of uranium-235 inside of metal rods. Spent fuel is thermally hot as well as highly radioactive and requires remote handling and shielding. High-level radioactive waste primarily is uranium fuel that has been used in a nuclear power reactor and is "spent," or no longer efficient in producing electricity. Regulations establish minimum acceptable performance criteria for licensees managing wastes, while providing for flexibility in technological approach. The NRC also regulates high-level wastes generated by the Department of Energy that are subject to long-term storage and not used for, or part of, research and development activities. The NRC regulates the storage and disposal of all commercially generated radioactive wastes in the United States. Low-level waste comes from reactor operations and from medical, academic, industrial and other commercial uses of radioactive materials. High-level waste is primarily spent fuel removed from reactors after producing electricity. There are two broad classifications: high-level or low-level waste. Radioactive waste is also generated while decommissioning and dismantling nuclear reactors and other nuclear facilities. Radioactive (or nuclear) waste is a byproduct from nuclear reactors, fuel processing plants, hospitals and research facilities. Responsibilities of Other Government Agencies.
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