Fukui Prefecture in Japan Likely to Approve KEPCO's Dry Storage Facility for Spent Nuclear Fuel

According to multiple officials of Fukui Prefecture, Japan, Governor Takato Ishida of Fukui Prefecture is expected to approve Kansai Electric Power Company's (KEPCO) construction of a dry storage facility for spent nuclear fuel at its nuclear power plants within the prefecture. If completed, this would mark the first adoption of such an on-site interim storage facility at KEPCO's nuclear power plants.

A dry storage facility is used to store spent nuclear fuel discharged from reactors. The basic approach involves placing spent fuel into dedicated metal containers and cooling them naturally through air circulation, without relying on electrical systems. Since the containers themselves can be transported by ship or trailer, subsequent off-site transfer is relatively convenient; even in the event of a power outage, the associated accident risk is considered low. Nuclear power plants operated by Japan Atomic Power Company (JAPC) and Shikoku Electric Power Company have already adopted this storage method.

KEPCO currently stores spent nuclear fuel in spent fuel pools at its nuclear power plants in Mihama, Oi, and Takahama towns in Fukui Prefecture. As of the end of April, the storage capacity utilization of spent fuel pools at the three nuclear power plants had reached approximately 80% to 90% of design capacity. KEPCO plans to transport spent fuel to off-prefecture interim storage facilities by the end of 2035 at the latest, and believes that first transferring the fuel from spent fuel pools to dry storage facilities will help enhance flexibility in subsequent transport arrangements.

Under the relevant concept, fuel in the dry storage facilities will be transferred to interim storage facilities in the future, and then processed at the reprocessing plant currently under construction by Japan Nuclear Fuel Limited (JNFL) in Rokkasho Village, Aomori Prefecture, to extract reusable materials such as uranium. However, KEPCO has not yet determined the specific site for the off-prefecture interim storage facility. Some prefectural assembly members are concerned that spent fuel may remain in the dry storage facilities for an extended period; KEPCO has stated that, in principle, it will not use the facility merely as a means to expand on-site storage capacity.

The Nuclear Regulation Authority of Japan has approved the installation of dry storage facilities at the Mihama and Takahama nuclear power plant sites. Under the safety agreement signed by KEPCO, the project also requires approval from the prefectural government and relevant local governments. Mihama and Takahama towns have already approved the relevant agreements this month, and the largest party in the Fukui Prefectural Assembly has also urged the Governor to make an approval decision during the June prefectural assembly session.

Takato Ishida has previously stated that he will make a judgment as soon as possible after gathering the necessary information. Officials of Fukui Prefecture stated that the Governor is expected to hear further opinions at the plenary session of the prefectural assembly scheduled for the 28th of this month, and indicate whether he agrees to the construction of dry storage facilities at the two nuclear power plants.