United States Nuclear Regulatory Commission - Protecting People and the Environment
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High-level waste

The highly radioactive materials produced as byproducts of fuel reprocessing or of the reactions that occur inside nuclear reactors. HLW includes:

  • Irradiated spent nuclear fuel discharged from commercial nuclear power reactors
  • The highly radioactive liquid and solid materials resulting from the reprocessing of spent nuclear fuel, which contain fission products in concentration (this includes some reprocessed HLW from defense activities and a small quantity of reprocessed commercial HLW)
  • Other highly radioactive materials that the Commission may determine require permanent isolation

Page Last Reviewed/Updated Tuesday, October 28, 2014