Kansai Electric Power applied to the Nuclear Regulation Authority (NRA) on Thursday to continue operating the No. 1 reactor at its Takahama nuclear power plant after the facility reaches 50 years of operation in November 2024.
The power utility submitted changes to the plant's safety regulations, including plans for the inspection and maintenance of the reactor for the next 10 years.
The No. 1 reactor at the Takahama plant in Fukui Prefecture is the oldest active reactor in Japan. It was commissioned in November 1974.
The NRA has approved an extension of the reactor's operating life to 60 years, but Kansai Electric must obtain the regulator's approval of the submitted documents, including soundness assessments, before the reactor reaches its 50th anniversary.
Kansai Electric conducted soundness assessments on about 4,000 pieces of equipment, and determined that it can ensure the soundness of the equipment until the 60th anniversary by implementing four additional maintenance measures, including replacing the reactor's internal structures and inspecting parts that were found to have deteriorated at other plants.
On Thursday, the company reported the details of its application to the governments of Takahama and Fukui Prefecture, which host the nuclear plant.
Yuichiro Sakamoto, head of the prefectural government's disaster prevention and safety department, urged the company to "carefully explain to the people of the prefecture about how safety will be ensured."
"The prefecture's expert committee will check the details of the assessments and the result of the central government's screening," Sakamoto said.
In May this year, Japan enacted a law to allow power utilities to effectively operate nuclear reactors for more than 60 years. Based on the law, a new system will start in June 2025.