A court rejected Wednesday a lawsuit seeking to block the restart of a nuclear reactor in western Japan due to safety concerns, dismissing the plaintiffs' claim that evacuation plans in the event of a natural disaster are inadequate.

The decision by the Matsue branch of the Hiroshima High Court came ahead of the planned restart by Chugoku Electric Power Co. in December of the Shimane nuclear plant's No. 2 reactor, which is currently undergoing a safety inspection.

"There are no specific risks of a major accident that may lead to a leak of an abnormal level of radiation beyond the premises of the plant," said Presiding Judge Yoshiki Matsutani.

The No. 2 unit is a boiling water reactor identical to those at the Fukushima Daiichi nuclear power station, which was crippled in the wake of a massive earthquake and tsunami in March 2011.

Plaintiffs carry banners after the Matsue branch of the Hiroshima High Court rejects their lawsuit in Matsue, Shimane Prefecture, on May 15, 2024. (Kyodo)

The unit is slated to become the second of its type to resume operation, following the planned restart in September of the No. 2 reactor at Tohoku Electric Power Co.'s Onagawa plant in Miyagi Prefecture.

Some of the plaintiffs came out of the court at around 10 a.m. and held banners saying "The judiciary abandoned the residents" and "Our voices did not reach (them)."

The plaintiffs from Shimane and Tottori prefectures had claimed that the utility's safety measures to deal with natural disasters, such as a major earthquake or a volcanic eruption at Mt. Sanbe, are inadequate.

They also argued that the evacuation plans drawn up by the government and municipalities fail to take into account factors such as collapsed homes or disruption to road networks in the event of a disaster, as seen in the Noto Peninsula earthquake on New Year's Day.

Following the ruling, Chugoku Electric Power released a statement describing the decision as "reasonable" and vowing that the utility will continue to prioritize and ensure safety.

The utility had argued that the reactor is safe, saying there would be no immediate issues in the event of a quake that is more powerful than that envisaged in its contingency plan and the possibility of a major eruption at the volcano is low.

The power company had planned to restart the reactor in August this year but pushed the date back to December due to delays in implementing its safety measures. The reactor had been cleared to restart after passing an inspection by the Nuclear Regulation Authority in September 2021.

The Shimane nuclear plant is the only one in Japan located in a prefectural capital. About 450,000 people across six municipalities in the two prefectures live within a 30-kilometer radius of the plant, a zone that must be covered by central and local government evacuation plans for natural disasters.

The high court decision came after the Matsue District Court in 2010 ruled against the plaintiffs.

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