Sweden disposes of low-level short-lived radioactive waste at its
Final Repository for Radioactive Operational Waste (SFR), in granite
rock 50 meters (164 feet) below the Baltic Sea. The SFR is 60 meters
offshore, connected by a tunnel to the site of the Forsmark nuclear
power plant in central Sweden. The first of its kind in the world,
the SFR has been in operation since 1988. Radioactive waste will remain
at SFR for 500 years, until its radioactivity is reduced to acceptable
The SFR uses a multi-barrier approach to containing radiation. Some
low-level radioactive waste is put into large rock vaults of granite
bedrock. Other low-level radioactive waste is put into silos surrounded
by protective barriers of clay and concrete.
After an initial one-year cool down period at the nuclear power facility,
spent nuclear fuel is sent to Sweden’s Central Interim Storage Facility
for Spent Nuclear Fuel, or CLAB, located in Oskarshamn in southern
Sweden. During the first 30 years at CLAB, spent nuclear fuel cools
in water in an underground rock cavern built to shield against radiation
release. Construction is underway to enlarge the facility.
Sweden’s spent nuclear fuel was sent to France for reprocessing until
the mid 1980s, when it was decided by Swedish authorities that disposal
would be less costly than reprocessing.
Sweden has operated a radioactive waste sea transport system since
1985. A specially built ship, the M/S Sigyn, carries all radioactive
waste between nuclear facilities and CLAB.
Extensive research into deep geologic disposal has been in progress
since the late 1970s. Following interim storage at CLAB, copper waste
canisters of spent nuclear fuel will be shipped to a deep repository
in granite bedrock. The canisters will be embedded in special clay
called bentonite, which will swell and encase the canisters after
groundwater fills the space between the rock and the clay.
Sweden is considering implementing its repository concept in stages.
For instance, it may place 10 percent of its spent nuclear fuel waste
into the repository, then wait for a number of years so that the emplaced
waste can be monitored and evaluated.