Kansai and Tohoku Electric to Store Spent Fuel at Mutsu Interim Storage Facility

Tokyo Electric Power Company Holdings (TEPCO), the Japan Atomic Power Company (JAPC) and Recyclable-Fuel Storage Company (RFS) submitted a new medium- to long-term spent fuel delivery plan for the Recyclable-Fuel Storage Center in Mutsu City, Aomori Prefecture, to the city government on 18 September. The plan was drawn up in cooperation with Kansai Electric Power and Tohoku Electric Power and includes spent fuel from the two utilities for the first time.

Under the new plan, a total of 5,000 tonnes of spent fuel will be delivered to the facility: 3,500 tonnes from TEPCO, 900 tonnes from JAPC, 500 tonnes from Kansai Electric and 100 tonnes from Tohoku Electric.

The original plan also envisaged the delivery of 5,000 tonnes of spent fuel. However, changes in nuclear power plant operations following the Great East Japan Earthquake of 2011 made it increasingly likely that deliveries from TEPCO and JAPC alone would fall short of that amount.

In December 2025, following a request from Mutsu City to fulfil the original plan and taking into account factors including its contribution to Japan's Strategic Energy Plan, the companies informed Aomori Prefecture and Mutsu City of the need to review the plan. In August this year, Mutsu asked them to reconsider the plan, including the possibility of cooperation among utilities. After other electric utilities were approached, Kansai Electric and Tohoku Electric expressed their intention to participate, leading to the submission of the new plan.

Kansai Electric has previously set out a policy of securing an interim storage facility outside Fukui Prefecture and commencing operations around 2030.

Deliveries of spent fuel from TEPCO to the Mutsu facility began in 2024. Under the newly announced plan, deliveries from Kansai Electric and Tohoku Electric are expected to begin around 2028. Annual deliveries are projected to reach 200 tonnes around 2030, with spent fuel continuing to be delivered to the first storage building, completed in 2013, until around 2040. Construction of a second storage building is planned to begin in the latter half of the 2030s.

Spent fuel will be stored at the facility for a maximum of 50 years. Shipments of spent fuel from the first storage building to Japan Nuclear Fuel Ltd.'s Rokkasho Reprocessing Plant are expected to begin around 2064 and be completed by November 2074. Shipments from the second building are expected to begin in the early 2080s and be completed in the latter half of that decade.

MORI Nozomu, chairman of the Federation of Electric Power Companies of Japan (FEPC), said at a regular press conference on the day of the announcement that cooperation among utilities is highly significant in providing greater flexibility in spent fuel management. He stressed that interim storage facilities should, as a fundamental principle, be established and operated by utilities while gaining the trust and understanding of local communities.