A Japanese court on Tuesday rejected local residents' calls to halt an aging nuclear reactor at Kansai Electric Power Co.'s Mihama power plant in central Japan that started operations more than 40 years ago in what marked the first judicial decision over the safety of aging reactors.
While the residents sought an injunction to shut down the plant's No. 3 unit in Fukui Prefecture due to safety concerns, the Osaka District Court said there were no problems with quake resistance after the plant underwent reinforcement work against earthquakes.
Noting the plant also passed the Nuclear Regulation Authority's safety checks, Presiding Judge Naoya Inoue said, "There are no circumstances that call for judging its safety more carefully and rigidly" than the agency's new safety standards introduced in the wake of the 2011 Fukushima nuclear crisis.
The decision came as the government seeks to extend the maximum service period for the country's existing nuclear reactors beyond 60 years. The reactor is the only one that operates in Japan beyond the country's 40-year service period in principle.
Nine residents in Fukui, Shiga and Kyoto prefectures living within a 10- to 80-kilometer radius of the plant argued the reactor would not be able to withstand a massive earthquake due to the likelihood that facilities and equipment have deteriorated over time.
Such a situation poses a risk of exposure to radiation caused by the spread of radioactive materials, the residents said, adding that the current evacuation plan is not effective, as the route passes by other nuclear plants and destination sites are located where radioactive materials could reach.
Kansai Electric argued the safety of the reactor is ensured as it complies with the new regulatory standards established on lessons learned from the 2011 nuclear disaster caused by a massive earthquake and tsunami.
After the ruling, the utility said, "We will continue to work on improving our plant's safety and credibility and will take all possible measures for operation and maintenance with the understanding of the people of the host town and society."
In June 2021, the No. 3 unit became the first nuclear reactor to operate beyond 40 years under the new rules that limit a reactor's service period to 40 years in principle, although it can be extended by up to 20 years if approved by the Nuclear Regulation Authority.
The unit was halted just four months after being restarted as it failed to implement anti-terrorism measures in time and also suffered a water leakage before being started up again on Aug. 30 this year. It resumed operations on Sept. 26.
The No. 1 and No. 2 units of the Mihama plant were terminated in April 2015 in line with the 40-year limit.
