Final Disposal of Nuclear Wastes in Finland – Safety Case Perspective

Abstract

In Finland, the waste producer has the responsibility to manage nuclear wastes produced, including the final disposal. The Finnish nuclear power companies, Fortum and Teollisuuden Voima (TVO), dispose their own low and intermediate level wastes (LILW) in the repositories located at the nuclear power plant sites at Loviisa and Olkiluoto at a depth of approximately 100 meters. Furthermore, TVO is planning a near-surface disposal facility for very low level wastes at Olkiluoto. Having the whole chain from waste production, handling, transportation and disposal of the LILW within a single organisation has proven to be a straightforward and cost-effective way to manage and dispose of the nuclear waste produced. The disposal of spent nuclear fuel at Olkiluoto is carried out by Posiva, an expert organisation owned by the two nuclear power companies. Posiva submitted an operating licence application in 2021 and is aiming to start geological disposal of spent nuclear fuel in mid-2020s as the first operator in the world.

Demonstration of the long-term safety is a precondition for the final disposal and therefore it has been studied for decades in Finland. The long-term safety is addressed in a safety case, a report portfolio demonstrating compliance with the regulatory requirements. For instance, the safety case for Loviisa LILW repository 2018 [1] considers the operational and decommissioning wastes arising from the Loviisa nuclear power plant. The Finnish radiation and safety authority approved the safety case in 2019. It has been utilised in the operating licence application for the extension of the repository and its operating period in 2022. Another example is the safety case for TVO’s near-surface disposal facility, which is being utilised in the licencing process. The lessons learned - including the key uncertainties - are utilized in the further planning of the final disposal as well as in an on-going R&D-program.