31 Dec (NucNet): The nuclear waste management company Posiva has submitted a construction licence application for a final repository that will hold spent nuclear fuel from Finland’s four commercially operational nuclear reactor units as well as future units.
Posiva said the repository, in Olkiluoto on Finland’s southwest coast, will hold spent nuclear fuel from nuclear reactors operated by its owners, Teollisuuden Voima Oyj (TVO) and Fortum. Those reactors are Loviisa-1 and -2, Olkiluoto-1 and -2, Olkiluoto-3, which is under construction, and the proposed Olkiluoto-4.
The application was submitted to the government on 28 December 2012. Posiva said it was based on “more than 30 years of research and development work carried out ever since commissioning of the existing nuclear power plants”.
Posiva president Reijo Sundell said data gathered over the decades has confirmed the company’s views of the safety of geologic disposal.
The application is for a complex of two interconnected nuclear facilities – an above-ground encapsulation plant and an underground final repository. Posiva plans to operate the facility for 100 years.
The complex also includes facilities intended for the final disposal of nuclear waste created during the operation and decommissioning of the encapsulation plant.
The final repository will be built at a depth of 400 to 450 metres. It will consist of a tunnel network, to be built in stages, and related technical facilities.
Posiva said the suitability of the Olkiluoto bedrock for the final disposal of nuclear waste has been confirmed with the construction of an underground characterisation facility known as Onkalo. The data gathered through surveys carried out in Onkalo, as well as above ground, have been used to develop the criteria and procedures for locating the final disposal tunnels.
Earlier this month Posiva said that during the next few years it will carry out a series of tests in Onkalo to ensure “adequate competence” for all the phases of final disposal of nuclear materials.
The tests will include drilling disposal holes, installing the disposal canister, installing a bentonite buffer around the canister, and filling and plugging the deposition tunnel. Posiva will also develop and test new procedures and techniques, as well as machinery.