Chubu Electric Withdraws Hamaoka Screening Apps

Chubu Electric Power Co. announced the withdrawal of its regulatory screening applications for the No. 3 and No. 4 reactors at the Hamaoka nuclear plant in Shizuoka Prefecture. The company cited a report by an investigative committee of outside lawyers that identified critical failures in its internal processes. The decision follows a finding that certain engineering departments underestimated possible earthquake vibrations in the data submitted for the restart process.

The withdrawal is accompanied by significant leadership changes, as Chairman Satoru Katsuno and President Kingo Hayashi will resign from their positions. The move aims to address the misconduct identified in the screening delay and to restore credibility with regulators and the public. This action effectively pauses the restart timeline for the two reactors until the underlying issues with data integrity are resolved.

Engineering Data Underestimation Found

The investigative committee determined that specific departments within Chubu Electric suspected of underestimating seismic risk parameters in their submissions. This error affected the accuracy of the safety data required for the regulatory screening of the Hamaoka plant. The report suggests that the initial criticism from executives over the delay may have inadvertently pressured officials to engage in the data manipulation to meet targets.

The screening process is a mandatory step for restarting nuclear reactors in Japan, requiring rigorous assessment of external hazards like earthquakes. By withdrawing the applications, Chubu Electric acknowledges that the previously submitted data does not meet the required standards for safety assurance. This pause allows the company to rectify the engineering assessments before re-engaging with the regulatory authorities.

Leadership Accountability and Whistleblower Handling

The report highlighted a failure in the company's response to internal concerns raised by a whistleblower in 2019. It was found that Chairman Katsuno, who served as president at the time, was informed of a decision not to respond to the whistleblower. While the committee did not conclude that Katsuno readily approved the inaction, it stated that he should have exercised more careful judgment in handling the matter.

The resignation of both the Chairman and the President signals a break in the current management structure. This leadership change is intended to separate the new administration from the identified misconduct and to implement stricter oversight mechanisms. The company aims to prevent similar issues from arising in future regulatory submissions and operational decisions.

Regulatory Implications for Hamaoka

The withdrawal of the screening applications means that the Hamaoka plant will remain offline for the affected units. The regulatory process must be restarted from the beginning once the company addresses the data discrepancies. This delay impacts Chubu Electric's generation capacity in the central Japan region, potentially affecting its energy supply reliability in the short term.

According to reports from GN auto stocks/utilities: power plant, the situation underscores the strict compliance requirements for nuclear operators in Japan. The company must now focus on rebuilding trust with regulators and the local community in Shizuoka Prefecture. The outcome of the internal investigation and the subsequent leadership transition will be closely monitored by stakeholders in the energy sector.