M/S Sigyn transports ...
The waste from the nuclear power stations is transported by M/S Sigyn, a vessel that was specially built to transport spent nuclear fuel and other radioactive waste.
… spent fuel to the interim storage facility ...
Spent nuclear fuel, which is the most difficult type of waste to handle, must be radiation-shielded and cooled prior to final disposal. This takes place in our interim storage facility in Oskarshamn, where it is submerged in water basins 25–30 metres below ground level. During the years of interim storage the radioactivity and heat development decrease by about 90 per cent.
... and short-lived waste to the final repository
Operational waste is usually low and intermediate-level, and does not need to be isolated for as long as spent nuclear fuel. A final repository for radioactive operational waste, SFR, was commissioned in Forsmark in 1988. Protective clothing, replaced parts from the nuclear power plants and filter mass that has been used to purify the water in the reactors are brought here. Medical, industrial and research-related radioactive waste is also stored here.
After interim storage comes encapsulation
After radioactivity decrease and cooling in interim storage the spent nuclear fuel is ready for encapsulation. The copper canisters have ductile iron inner containers and hold about two tonnes of waste each. There will eventually be a total of about 6,000 canisters. The plan is for construction of the encapsulation facility – probably adjacent to the interim storage facility – to begin in a few years.
And finally, the Spent Fuel Repository
A final repository with tunnels is to be built in Swedish primary rock, between 400 and 700 metres below ground level. This is where spent nuclear fuel will finally be deposited. Read more under The long-term solution.