Chubu Electric Withdraws Hamaoka Screening Apps After Internal Investigation

Chubu Electric Power Co. announced on Monday that it will withdraw its applications for the regulatory screening of reactors No. 3 and No. 4 at the Hamaoka nuclear power plant. The company stated that this decision follows the release of an internal investigation report detailing significant misconduct within its engineering divisions.

As part of the corrective measures, Chairman Satoru Katsuno and President Kingo Hayashi will resign from their positions. The withdrawal effectively halts the immediate timeline for restarting these units, which are located in Shizuoka Prefecture, pending further regulatory and operational review.

Engineering Data Mismanagement Identified

An investigative committee composed of outside lawyers found that several Chubu Electric departments underestimated possible earthquake vibrations in the data submitted for regulatory screening. This data was critical for the safety assessment required to restart the two reactors. The committee concluded that the initial underestimation of seismic risks compromised the integrity of the application process.

The report indicates that executive criticism of the screening delay may have contributed to the behavior of the officials involved. By pressuring staff to meet timelines, leadership inadvertently encouraged the manipulation or insufficient analysis of seismic data. This creates a direct causal link between internal management pressure and the technical deficiencies identified by the investigators.

Whistleblower Concerns Ignored in 2019

The investigation also uncovered that Chairman Satoru Katsuno, who served as president at the time, was informed of a decision not to respond to a whistleblower in 2019. The individual had raised internal concerns regarding the plant's safety procedures. The committee noted that while Katsuno did not explicitly order the suppression, he failed to exercise the careful judgment required to address such critical safety flags.

This finding highlights a breakdown in the company's internal governance and risk management protocols. The inability to act on whistleblower reports suggests a systemic issue in how Chubu Electric handles internal dissent and safety-related feedback. The resignation of top executives is a direct response to this failure in leadership oversight.

Regulatory Implications for Nuclear Restart

The withdrawal of the screening applications removes the current pathway for restarting the Hamaoka reactors. Regulatory screening is a mandatory step in Japan's nuclear restart process, and without a valid application, the plant cannot proceed to the next stage of operational approval. This move aligns with the company's need to rebuild credibility with regulators and the public.

According to the report cited by GN auto stocks/utilities: power plant sector analysts, the incident underscores the rigorous scrutiny now applied to nuclear operators in Japan. The company must now undergo a thorough review of its entire data submission process and governance structure before any future applications can be considered. The resignation of key figures signals a reset of the company's internal compliance framework.