Case – Responsible final disposal of nuclear waste

Finland is one of the most successful countries in the use of nuclear energy; the country’s four nuclear power plant units have achieved the world’s highest load factors every year of the 21st century. Nuclear power produces almost a third of the country's electricity.

In Finland, the management of the entire power plant life cycle is a precondition for sustainable nuclear electricity production. Posiva, founded by its owners Fortum and TVO (Teollisuuden Voima), will conduct the final disposal of spent nuclear fuel from both currently operational nuclear power plants, Loviisa and Olkiluoto, in a responsible manner.

Final disposal begins in Finland, the first in the world

The deployment of the final disposal of spent nuclear fuel is planned to begin in Finland around the mid-2020s. Final disposal of Fortum's Loviisa power plant's spent nuclear fuel is scheduled to begin in the 2040s.

The final disposal facility for spent nuclear fuel will be constructed within the solid Olkiluoto bedrock with no major fractures at a depth of 400–450 meters. The potential effects of changes above ground and in the atmosphere, and the effects of human activities on the immediate surroundings of the repository, have been taken into account in the design of the final disposal concept.

Final disposal is based on the use of multiple release barriers, which guarantee that nuclear waste cannot come into contact with organic nature or people. These barriers include the state of the fuel, the final disposal canister, the bentonite buffer, the backfilling of the repository tunnels and the surrounding Olkiluoto bedrock.

The final disposal solution for spent nuclear fuel has also been examined through environmental impact assessments. Environmental responsibility for final disposal is also on a financially sustainable foundation because, in Finland, nuclear power companies must cover the costs of nuclear waste management, and the requisite funds are set aside in the State Nuclear Waste Management Fund.


  • Check Olkiluoto has been selected as the final disposal site on the basis of site surveys and a safety analysis.
  • Check Olkiluoto bedrock is crystalline bedrock, which constitutes the majority of Finnish bedrock. Finnish bedrock is among the oldest in the world.
  • Check The final disposal facility will be at a depth of approximately 430 meters.
  • Check Total length of the ONKALO® tunnels is 42 km.
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