Japan’s Saga District Court on 20 March rejected a request by residents to suspend the planned restart of Genkai 3&4 over safety concerns. The two 1127MWe pressurised water reactors, operated by Kyushu Electric Power Co, began commercial operation in the mid-1990s.

Some 70 people had sought an injunction to halt the restart of the reactors citing the risk of a volcanic eruption in the region. Genkai 3 reactor is scheduled to restart on 23 March followed by Genkai 4 in May. Presiding Judge Takeshi Tachikawa said the utility’s safety measures were “reasonable” and found “no specific risk of (the reactors) causing serious damage”. The court said no magma reservoir had been confirmed in the layers of earth up to 10km beneath the surface of the volcano.

The decision was in contrast with a December Hiroshima High Court ruling to stop the planned restart of a reactor at Shikoku Electric Power Co’s Ikata nuclear plant because of the possible eruption of Mount Aso, which is located some 130km from both stations. During the trial, plaintiffs from Saga, Fukuoka, Nagasaki, Kumamoto and Yamaguchi prefectures expressed doubt about the credibility of post-Fukushima safety standards and said there were no measures in place to respond to a catastrophic volcanic eruption. In June 2017, Tachikawa had dismissed a similar request from a different group of residents for an injunction to stop the restart of the two Genkai reactors.

Asahi Shimbun reported that the plaintiffs plan to appeal to the higher Fukuoka High Court. In separate lawsuits, some 10,000 people in Japan and abroad have filed a suit demanding suspension of the Genkai reactors. However, the Town Assembly in Genkai on 21 March reaffirmed its support for nuclear energy and also approved a proposal by the National Nuclear Community asking the central government to support the construction of new reactors in its Strategic Energy Plan.

On 19 March, the Hakodate District Court in Hokkaido prefecture in northern Japan had rejected a lawsuit aimed at stopping the construction and subsequent operation of Japan Electric Power Development Corp's (J-Power's) Ohma nuclear plant, being built in Aomori prefecture.  More than 1100 residents in Hokkaido, among others, had filed the lawsuit in 2010 to prevent the 1383MWe advanced boiling water reactor from starting.  Ohma 1 will be the first Japanese reactor fuelled solely by mixed oxide (Mox). Construction began in 2008 (delayed from 2007) with operation set for 2014 but was suspended after Fukushima in 2011.  Work resumed in 2012 but faced further delays because of the need to satisfy new safety requirements. The station is about 38% complete.

In December 2014, J-Power applied to the Nuclear Regulation Authority (NRA) to make changes intended to strengthen the unit's protection, including tsunami countermeasures, ensuring power supplies, ensuring heat removal functions, and severe accident responses. These were expected to be completed by the end of 2020, but in 2015, the company announced a year’s delay in the start of safety equipment construction, deferring operation to 2021 to allow for the prolonged NRA screening process. In 2016, A year later, J-Power announced another two-year delay saying it expects construction of the safety upgrades to begin this year for completion in fiscal 2023. The operation is now set for 2024/25.
The lawsuit focused on the risk of volcanic eruptions,  the possible presence of an active seismic fault in the seabed near the plant site, and concerns about the use of Mox fuel.

Photo: Map showing licensing status of Japanese nuclear facilities