The world’s nuclear power plants generate 12,000 tonnes of high-level waste and spent fuel each year. In countries with open fuel cycles, in which fuel is not reprocessed, the spent fuel is cooled for about 20 years in pools of water and then stored in dry casks on plant property to await completion of appropriate permanent repository facilities.
Repositories for disposal of low-level and intermediate radioactive wastes are operating in a number of countries, but high-level wastes require more secure disposal.