Court decisions divided over risk evaluations of nuclear reactors

Japanese courts have been divided in their decisions over residents' petitions for provisional injunctions ordering the suspension of nuclear reactors filed across the country, and the fate of reactor reactivation is likely to remain in the hands of judicial rulings.

On April 6, the Miyazaki branch of the Fukuoka High Court approved the operation of the No. 1 and 2 reactors at the Sendai Nuclear Power Plant in Kagoshima Prefecture, dismissing residents' petition for a provisional injunction ordering the suspension of the reactors.

Unlike the Otsu District Court's injunction in March ordering the No. 3 and 4 reactors at the Takahama nuclear plant in Fukui Prefecture be halted, the Fukuoka High Court branch acknowledged that social norms do not call for a "zero risk" over the possibility of nuclear accidents.

After the Fukushima No. 1 nuclear power plant meltdowns in March 2011, there were nine court decisions over injunction requests for nuclear reactors. Of them, three decisions ordered the reactors be halted -- the aforementioned Otsu District Court decision, the May 2014 Fukui District Court decision over the Oi nuclear plant in Fukui Prefecture, and the same court's April 2015 decision over the Takahama plant.

In response to the April 6 decision by the Fukuoka High Court's Miyazaki branch, petitioners are set to consider whether to appeal it to seek the Supreme Court's decision. There are other pending petitions and lawsuits over nuclear reactors across the country, including the one over the No. 3 reactor at the Ikata nuclear plant in Ehime Prefecture, which operator Shikoku Electric Power Co. is seeking to restart this coming summer.

Court decisions over nuclear reactors are split over how far accident risks carried by nuclear reactors are tolerated by social norms. The Fukuoka High Court branch's decision pointed out that unpredictable risks would remain even if the scientific and technical knowledge reflected in the new regulatory standards adopted by the Nuclear Regulation Authority (NRA) is updated, and concluded that "while risks remain, it cannot be said there is a concrete danger" -- in defiance of the Otsu District Court's decision that called for a zero nuclear accident risk.

Courts were also divided in their opinions over resident evacuation plans. The Fukuoka High Court's Miyazaki branch ruled in favor of Kyushu Electric Power Co., the operator of the Sendai plant, on the grounds that the central government has approved the utility's nuclear evacuation plans, saying, "Even if the plans lack in rationality and effectiveness, they are not recognized to immediately infringe on residents' personal rights."

With regard to the NRA's volcano risk evaluation guide premised on detecting signs of major eruptions, the high court branch raised questions by saying, "We must say eruption predictions are difficult and unreasonable." The high court branch, however, went on to state, "The danger of catastrophic eruptions can be ignored" -- again defying a zero risk theory.

At a regular press conference on April 6, NRA Chairman Shunichi Tanaka refuted the high court branch's decision, saying, "It is the NRA's view that elaborate observations should be made for early predictions of eruptions and prompt responses should be made," ruling out the possibility of reviewing its volcano risk evaluation guide.

Shigeyuki Suto, professor of the Faculty of Law at Waseda University, criticized the decision by the Fukuoka High Court's Miyazaki branch, saying, "The decision lacks in an attitude that questions from the public point of view whether the new regulatory standards drawn up by a group of experts are reasonable or not. The decision that the nuclear reactors (at the Sendai plant) are not subject to immediate suspension even if resident evacuation plans are insufficient was also a sheer formality."