Storage of spent fuel elements and high-level radioactive waste
The cask storage hall, 68m long, 41m wide and almost 20m high, lies at the heart of the interim storage facility. This hall is used to store vitrified high-level waste from the reprocessing plants and spent fuel elements from the Swiss nuclear power plants. The highly radioactive vitrified waste and spent fuel elements are stored in tightly sealed transport and storage cask (TLB). At full capacity, this hall has room for around 200 standing casks.
The principle of the dry storage of vitrified highly ative waste and spent fuel elements is a safe and much tested concept. The highly active waste emits heat. This heat must at all times be able to escape. The heat can always dissipate thanks to the natural circulation of air through openings in the side walls of the hall and in the roof. Initially, the heat output of a steel casks filled with high-level radioactive waste can amount to between 40 and 50 kilowatts. The heat output drops continuously and equals only around 25 to 30 kilowatts after ten years in interim storage. Given the current state of the technology, it is not yet possible to use this heat potential economically. The hot air released through the openings in the roof is not radioactive and does not have any negative impact on the environment.