Chubu Electric Withdraws Hamaoka Restart After Data Fraud

Chubu Electric Power Co. announced on September 14 that it is withdrawing its application to the Nuclear Regulation Authority for the restart of the Hamaoka nuclear plant. The utility stated that this decision follows an internal investigation which identified systematic manipulation of seismic data intended to expedite the regulatory approval process for two reactors in Shizuoka Prefecture.

In response to the findings, President Kingo Hayashi and Chairman Satoru Katsuno will resign at the end of the month. The company cited a breakdown in internal controls and a culture that tolerated rule-breaking when employees believed safety standards were not compromised, leading to significant damage to stakeholder trust.

Investigation Reveals Systematic Data Manipulation

The report from a committee of three external lawyers, released on September 11, found that 208 of 225 earthquake assessments at the Hamaoka plant contained manipulated figures. The misconduct, which dates back to at least 2012, involved altering calculated seismic ground motion data to prevent values from exceeding the 1,200-gal threshold assumed in the company’s restart application. Exceeding this level would have triggered additional safety assessments and construction costs, thereby delaying the return of the reactors to service.

The committee determined that management pressure to avoid delays in the regulatory review process was a primary driver of the misconduct. Employees developed a justification theory that allowed rule violations if they believed the actions did not directly compromise safety, a mindset that persisted despite the critical nature of seismic data in nuclear licensing.

Executive Resignations Follow Accountability Findings

Chairman Satoru Katsuno, who served as president from 2015 to 2020 and chairman since, acknowledged his responsibility for the failure to prevent the incident. The investigation noted that his comments criticizing the slow progress of the review process, describing it as moving like an inchworm, acted as pressure on staff. Katsuno stated he intended to advance goal management but recognized he bears heavy responsibility for the resulting misconduct.

President Kingo Hayashi, who succeeded Katsuno in 2020, offered deep apologies for the repeated incidents of misconduct. He acknowledged his role in rebuilding nuclear power operations and the severe damage caused to the trust of society and local residents. Both executives’ departures mark a complete turnover in the company’s top leadership amid the ongoing regulatory scrutiny.

Utility Plans Restart After Trust Restoration

Despite withdrawing the current application, Chubu Electric maintains that the importance of the Hamaoka nuclear plant remains unchanged. The company intends to pursue a restart only after it has fully restored public trust and addressed the internal control failures identified in the investigation. This withdrawal effectively halts the operational timeline for the two reactors, pending further regulatory and public confidence measures.