Kansai Electric Power Revises Site Survey Plan for Additional Units at Mihama Nuclear Power Station

en.Wedoany.com Reported - On September 9, 2026, Kansai Electric Power Company (KEPCO) announced a revision to its voluntary site survey plan for additional units at the Mihama Nuclear Power Station, extending the completion of the preliminary survey from March 2027 to March 2028, while the detailed survey remains scheduled for completion in 2030.

KEPCO stated that, regarding the potential additional units at the Mihama Nuclear Power Station, it resumed the voluntary site survey on November 5, 2025, which had been suspended since March 12, 2011. Under the original plan announced on September 17, 2025, KEPCO first conducted a broad preliminary survey both inside and outside the plant site, then selected a more advantageous area based on geological conditions, and carried out a detailed survey in that area.

The preliminary survey results to date indicate that both the northern and southern areas of the Mihama site contain bedrock with sufficient strength for the installation of facilities such as reactors. Additionally, no structures such as potentially active faults have been identified at this stage.

As the survey results obtained so far from the two areas are similar, KEPCO plans to add borehole investigations and expand data to further assess which area is more suitable for siting facilities such as reactors from the perspective of geological and foundation conditions. Under the revised plan, 8 additional boreholes will be added in the northern area and 5 in the southern area, with the exact number subject to adjustment as the survey progresses.

Following the revision, the preliminary survey period runs from November 2025 to March 2028, with the detailed survey scheduled to commence in April 2028 and be completed in 2030. The preliminary survey includes borehole investigations, seismic wave exploration, and surface reconnaissance; the detailed survey includes trial pit investigations, seismic wave exploration, deep and shallow measurements, borehole investigations, and earthquake-related surveys.

KEPCO stated that the decision on whether to construct additional units will not be based solely on the results of this survey, but will also take into account factors such as the progress of innovative light-water reactor development, regulatory policies, and the business environment necessary for investment decisions. The company said it will continue to prioritize safety, promote the safe and stable operation of the nuclear power station, and conduct nuclear power business with the understanding and support of the local community and the public.