Application in for Finnish repository

02 January 2013

Management of used nuclear fuel in Finland has reached a milestone with the application by Posiva to construct a final repository and waste encapsulation plant at Olkiluoto.

Olkiluoto repository
The Olkiluoto repository will consist of a network of disposal tunnels up to 450 metres below ground (Image: Posiva)

Leading the project is Posiva, a waste management specialist jointly owned by Finnish nuclear utilities Fortum and TVO. It submitted the application to the Ministry of Employment and the Economy on 28 December with the aim of permanently storing the used nuclear fuel from its owners' nuclear power plants. The application covers the construction of the encapsulation plant and repository, as well as for facilities for the final disposal of waste created during the operation and decommissioning of the encapsulation plant.

The encapsulation plant will encase used fuel assemblies in steel and copper canisters ready to be embedded in clay within the repository's network of tunnels. Built at a depth of 400-450 metres, the repository will dispose of 9000 tonnes of used fuel from the country's four existing reactors - Olkiluoto units 1 and 2 and Loviisa units 1 and 2 - as well as the first-of-a-kind EPR under construction at Olkiluoto 3 and the planned fourth unit at Olkiluoto.

Posiva president Reijo Sundell commented, "The construction licence application is based on more than 30 years of research and development work, carried out ever since the commissioning of the existing nuclear power plants. The data gathered over the decades has confirmed our views of the safety of geological disposal."

The site for Posiva's repository at Eurajoki near Olkiluoto was selected in 2000. Posiva noted that the suitability of the Olkiluoto bedrock for the final disposal of radioactive waste has been confirmed with the construction of the underground characterisation facility known as Onkalo.

The fulfilment of the long-term safety requirements is discussed in the safety case prepared for the licence application, submitted to the Radiation and Nuclear Safety Authority (Stuk) for appraisal. Posiva senior vice president for research Juhani Vira said, "Even in the unlikely case that several canisters break at the same time, the releases of radioactive substances would remain at one-tenth of the limits set by the Stuk at the most."

The Ministry of Employment and the Economy noted that the processing of the construction licence application includes a hearing procedure, as provided in the Nuclear Energy Act. The ministry said that it would invite several ministries, other authorities and organizations, and the municipality of Eurajoki to comment on the application. The public and other stakeholders will also be invited to submit their comments. The hearing procedure will be launched in early 2013.

The ministry expects to forward the licence application and related materials for consideration by the government in late 2014.

If a construction licence is granted, an operating licence will still be required before the completed facility can start up. Final disposal operations at Olkiluoto are expected to begin around 2020 and to last for some 100 years before the repository is sealed.

Researched and written
by World Nuclear News