Japan’s Nuclear Regulation Authority (NRA) has terminated the safety evaluation process for two reactors at the Hamaoka nuclear facility following revelations that the plant operator systematically manipulated seismic risk data. The decision marks a significant impediment to the nation’s efforts to expand nuclear energy utilization.
Chubu Electric Power Company had submitted applications in 2014 and 2015 to resume operations at reactors No. 3 and 4 at the Hamaoka plant, situated approximately 200 kilometers west of Tokyo in a region historically vulnerable to massive Nankai Trough earthquakes. The facility’s two additional reactors are currently undergoing decommissioning while a fifth remains inactive.
The regulatory investigation commenced in February after authorities received whistleblower information regarding data integrity issues. NRA Chairman Shinsuke Yamanaka confirmed the suspension of safety assessments after verifying the falsification, with Chubu Electric formally acknowledging the misconduct in mid-December. The regulatory body is now contemplating inspections at the utility’s corporate headquarters.
Chubu Electric President Kingo Hayashi publicly admitted the improprieties on Monday, conceding that employees deliberately utilized inaccurate seismic measurements to minimize perceived earthquake risks. Hayashi offered formal apologies and committed to establishing an independent investigative panel.
Chairman Yamanaka characterized the data manipulation as “an act of betrayal that fundamentally undermines nuclear safety principles,” emphasizing that operators bear primary responsibility for ensuring safety protocols. The NRA indicated that any future screening processes would necessitate completely restarting the evaluation procedure, with potential for outright rejection of applications.
This development represents a substantial setback for Japan’s energy strategy, which has sought to accelerate nuclear reactor reactivation to address escalating energy expenses and carbon reduction commitments. Public sentiment remains polarized regarding nuclear power due to persistent safety apprehensions stemming from the 2011 Fukushima Daiichi nuclear disaster.
According to NRA statistics, Japan currently operates 13 of its 57 commercial nuclear reactors, with 20 non-operational units and 24 undergoing decommissioning procedures.