The power company had received a request from the mayor in February 2023 to consider regional development measures. In response, since August 2023, it has been conducting studies and assessments for installing a dry-storage type interim storage facility on its premises in Nagashima, Kaminoseki.
A major focus of the study was the ground conditions. If an active fault with potential future activity were located directly beneath the facility, it would be technically difficult to construct an interim storage facility. Accordingly, the company carried out detailed investigations, including boring surveys.
Based on objective data obtained from these surveys, the analysis confirmed the presence of three major active faults within a roughly 30 km radius on land and 35 active faults in the surrounding sea area. However, the company judged that the facility could be made viable by appropriately reflecting these findings in seismic design and other measures. The bedrock beneath the site was also confirmed to be suitable for the construction of an interim storage facility.
In addition, surveys of the surrounding natural environment—including weather, volcanic activity, hydrology, and ecosystems—as well as the social environment such as industrial activity and traffic conditions, confirmed that construction of the facility would not have adverse impacts. Thus, the study concluded that “there are no technical issues that cannot be addressed.”
The company now plans to formulate a business plan covering the scale of the facility and the start of construction. If launched, the project would become Japan’s second off-site interim spent fuel storage facility, following the Recyclable-Fuel Storage Center in Mutsu City, Aomori Prefecture. The Kaminoseki facility is planned for joint operation with Kansai Electric Power.
On its website, Chugoku Electric Power stated, “We will work to communicate the survey results clearly to local residents in order to further deepen understanding.”
