The Safety Aspects of Long Term Operation mission took place from 6 to 9 October and included two members of International Atomic Energy Agency (IAEA) staff and two experts from Argentina and the Netherlands.
Oskarshamn 3, a boiling water reactor, was commissioned in 1985, and its service life and production capacity were increased in 2009. The total power of the plant is about 1450 MWe and the annual production is around 11 TWh.
The unit currently has a planned operating period until 2045 but the owners of the plant – Uniper has a 54.5% share and Fortum 45.5% – announced in 2024 they were exploring a further 20-year operating extension of the plant, which would take it to 80 years.
Mission leader, IAEA Nuclear Safety Officer Bryce Lehman, said: “The team noted the plant is working on the suggestions and recommendations from the 2024 review. The plant has made improvements in the ageing management of unit 3, addressing many of the areas identified for improvement in 2024.”
The team found that the plant had updated the Long Term Operation (LTO) programme “ensuring that all Long Term Operation activities are systematically planned, and clear responsibility is assigned for completing necessary activities” as well as finalising the ageing management scope for LTO.
Areas for further work included ensuring that the plant safety analysis report “is properly updated to reflect the ageing management activities, especially regarding time-limited ageing analyses (TLAAs) – assessments of ageing effects on plant components during long-term operation” and to ensure that TLAAs are “properly identified and revalidated, and properly incorporated into the ageing management”.
Jenny Wirandi, Acting CEO of OKG, said such missions were “an important tool for ensuring that OKG remains aligned with IAEA standards and guidance in this area – the reviews strengthen our Ageing Management Programme and support our ambition to achieve safe, reliable and sustainable LTO”.
A final copy of the report will be submitted to the plant management, the Swedish Radiation Safety Authority and the Swedish government within three months.
