Finland is offering the first practical answer to one of the most vexing questions facing the international nuclear power industry and the IAEA: what should be done in the end with the spent fuel that remains harmfully radioactive for 100 000 years.
Finland's answer is deep geologic disposal. Its pioneering work on permanent storage is particularly important now as some 60 new countries explore with the IAEA whether nuclear power might be an answer to a sharp and expected jump in future energy demand and one that mitigates climate change.
"Waste disposal remains an important challenge that needs to be addressed in a safe and sustainable manner by (nuclear power) newcomers and established users alike. We can assist both," IAEA Director General Yukiya Amano told the IAEA General Conference in September 2010, adding that he wanted to expand Agency activities in sharing relevant best practices and disseminating information.
Finland's Solution
Posiva, established in 1995 by Finland's two nuclear power plant owner-operators, is responsible for research into final disposal and for the construction and operation of the disposal facility.
"We will take the spent fuel, place it in tight canisters, put the canisters underground, backfill all the rooms and seal the repository," says Timo Äikäs, executive vice president of Posiva.
The repository will be located in Finland's southwest, at Olkiluoto in Eurajoki. The ONKALO research tunnel, begun there in 2004, is used for bedrock studies and developing rock construction and disposal technology in real conditions.
The actual repository, for which Posiva is currently preparing to file for licences to build, will be constructed off the existing research tunnel. Storage is planned at 420 metres below ground. Deep disposal operations are scheduled to begin in 2020 and will take some 100 years.
Repository Size and Cost
Under parliamentary approvals to date, the planned repository could store some 9 000 tonnes of uranium, including storage of the 5 500 tonnes of uranium from Finland's four nuclear power plants, which went into operation roughly 30 years ago, as well as a fifth that is under construction and scheduled to go online in 2013. Potentially, it could be expanded to store the waste from additional nuclear power plants which are being considered by Posiva's owner companies TVO and Fortum. Posiva has conducted an assessment for the storage of up to 12 000 tonnes uranium.
By the end of 2009, Finland's nuclear power plants had the equivalent of 1 500 tonnes of uranium in temporary storage; each year, roughly an additional 70 tonnes accumulate.
The overall cost of the permanent storage facility is some €3.3 billion, which means Finnish electricity consumers will be charged 0.16 cent per kilowatt hour over the project's life-time to pay for it.
Challenge of Spent Nuclear Fuel
Various solutions have been mooted to deal with the hazardous radioactive material, but the only advanced projects deal with deep disposal: Sweden is pressing ahead with plans similar to Posiva's. Reprocessing is not a legitimate alternative, because it too results in heavily radiating, long-term fission products that would need a final disposal solution.
Spent nuclear fuel is currently stored temporarily at nuclear power plants in pools, or in protective canisters outside, in part because it needs to cool for 40 years before it can be disposed of.
"The 40 years wait is a good thing because it really gives you time to develop the disposal concept, look for a site, then do your technical engineering design and gain acceptance. This all takes time and is the reason why there are no operating disposal facilities," says Äikäs.
Concern and care for the safety of the disposal site and process underlies all Posiva's decisions.
"Whatever happens - canister disintegration, an earthquake or fault movement, an ice age - regardless, radiation would stay below the set limits. We know the disposal is very safe."