Posiva granted licence to operate world's 1st spent nuke fuel repository

The government on Thursday granted Posiva Oy a licence to operate an encapsulation plant and final disposal facility for spent nuclear fuel in Olkiluoto, Eurajoki until the end of 2070, said the Ministry of Economic Affairs and Employment in a press release.

This is the first final disposal facility for spent nuclear fuel in the world to receive an operating licence.

The operating licence authorised Posiva to encapsulate and permanently dispose of spent nuclear fuel from the Olkiluoto and Loviisa nuclear power plants.

Posiva is responsible for the safe implementation of the project while Posiva’s owners Teollisuuden Voima Oyj (TVO) and Fortum Power and Heat Oy (Fortum) are responsible for ensuring the sufficient financial prerequisites of the operations.

The government issued the licence following a favourable statement concerning the facility issued by the Radiation and Nuclear Safety Authority (STUK) on 4 August 2026.

According to the statement, the encapsulation and final disposal facility for spent nuclear fuel built by Posiva in Olkiluoto meets the safety requirements laid down in the Nuclear Energy Act and Decree. Due consideration has been given to the safety of the population and facility workers, as well as to environmental protection.

“Finland’s strong safety culture underpins the production of clean energy. It is our responsibility across generations to ensure the safe and responsible use of nuclear power, from construction through to the final disposal of spent fuel. As a result of more than 40 years of systematic efforts, Finland will launch the first final disposal facility for spent nuclear fuel in the world,” said Minister of Climate and the Environment Sari Multala in the press release.

The operating licence applies to a nuclear facility located in the Olkiluoto power plant area, which consists of an above-ground encapsulation plant and a final disposal repository, or Onkalo, built at a depth of over 400 metres.

The licence granted to Posiva covers the spent nuclear fuel generated by the nuclear power plants currently in operation in Finland. Posiva may possess, process, store and dispose of a maximum of 6,500 uranium tonnes (tU) of spent nuclear fuel generated by the Olkiluoto and Loviisa nuclear power plants.

In granting the operating licence, the government took account of the licence conditions set out by STUK in its statement. The licence conditions concern the final disposal facility for low-level and intermediate-level waste as well as the submission of a periodic safety assessment and an updated long-term safety justification.

Under the licence conditions, Posiva may possess, produce, process, store and dispose of low-level and intermediate-level nuclear waste generated by the encapsulation plant and final disposal facility and by the operation and decommissioning of nuclear facilities owned by its shareholders, provided that the total volume of the waste does not under any circumstances exceed 3,000 m³, of which no more than 1,500 m³ may be designated for final disposal.

The licence also permits the final disposal of certain other radioactive waste and nuclear materials generated in Finland to a limited extent. This includes certain radioactive waste generated in healthcare and research institutions.

The amount of spent nuclear fuel to be disposed of corresponds to approximately 3,300 disposal canisters. Once operations are fully established, the plan is to dispose of a maximum of 60 canisters per year at the plant. The final disposal operations are estimated to continue until the 2120s, after which the repository will be backfilled and closed. After the closure of the facility, responsibility for the spent nuclear fuel will be transferred to the State in accordance with the Nuclear Energy Act.

Posiva must ensure that the data sets essential for the final disposal operations are specified and stored to make them available to the state after the closure of the final disposal facility.

STUK will supervise Posiva’s operations during the completion of the commissioning and the operation of the facility and can, if necessary, require remedial and other measures to improve safety.

Before the facility is commissioned, STUK will conduct the inspection referred to in section 20 of the Nuclear Energy Act to ensure that all conditions for safe operation have been met. Despite the decision on the operating licence issued by the Government, Posiva may not start operating the facility before STUK has conducted the inspection.

Posiva is required to submit a periodic safety assessment and an updated long-term safety justification to STUK within ten years of the granting of the licence. Periodic safety assessments will also be carried out during the operation of the facility in accordance with nuclear energy legislation.