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Third reactor restart in Japan

Nuclear Monitor Issue: 
Jim Green – Nuclear Monitor editor

Kansai Electric Power Co's (KEPCO) reactor #3 in Takahama, Fukui Prefecture restarted on February 1. It had been offline since February 2012 and is the third reactor to restart after two reactors at Kyushu's Sendai plant restarted last year. Forty reactors remain shut down, in addition to those that have been permanently shut down.

The restart of Takahama #3 has been tortuous. KEPCO first applied to the Nuclear Regulatory Authority (NRA) for permission to restart Takahama #3 and #4 in July 2013. It subsequently submitted various amendments to its plans. In February 2015, the NRA gave its permission for KEPCO to make the required safety upgrades. The restart process was delayed by an injunction imposed by the Fukui District Court in April 2015, citing safety concerns, but the ruling was overturned in December 2015.

Risk analysis and emergency planning

The Tokyo-based Citizens Nuclear Information Center argued in early 2015 that the safety analysis presented by KEPCO and accepted by the NRA used numerous arbitrary figures and lacked credibility:1

"KEPCO claims that the analysis codes it uses in countermeasure scenarios against severe accidents are appropriate, and the NRA has approved this procedure. ... What this means is that KEPCO has carried out an arbitrary analysis in order to clear the numerical hurdles required by the regulatory requirements, and by saying that the regulatory requirements have been set conservatively, the NRA has then approved the analysis. There are far too many of these arbitrary usages of analysis codes to mention, and this procedure of using codes to whittle away the likelihood of the occurrence of accidents is an extremely serious problem."

The inadequacy of emergency planning is perhaps the most startling problem with the reactor restart process at Takahama and elsewhere. About 180,000 people reside within a 30 km radius of the Takahama plant.

Under the Act on Special Measures Concerning Nuclear Emergency Preparedness, prefectural and municipal governments within a 30 km radius of nuclear power plants are given full responsibility for emergency preparedness and evacuation planning. But their plans are not subject to NRA review.2

Thus emergency planning is uneven and generally inadequate. The Asahi Shimbun reported on 30 January 2016 that local government officials have voiced concern over the Takahama reactor restart as they have yet to map out detailed evacuation plans and to conduct drills.3

Nuclear Engineering International reported on 2 February 2016: "While there are plans on paper to evacuate some Fukui residents to Hyogo, Kyoto, and Tokushima prefectures, many municipalities there have no detailed plans for receiving evacuees. Kyoto Governor Keiji Yamada said he did not feel adequate local consent had been obtained, citing concerns about evacuation issues. Shiga Governor Taizo Mikazuki said there was a lack of sufficient disaster planning."4 Likewise, Mayor Ryozo Tatami from the port city of Maizuru in Kyoto Prefecture called for strengthened emergency planning.5

Kyoto-based Green Action said in a 28 January 2016 statement:6

"Nearly 180,000 people must evacuate from Fukui and Kyoto prefectures in the event of a serious accident at the Takahama plant. Small children near the plant remain unprotected. Their parents must battle through congested traffic just to get potassium iodine pills. Green Action as part of a coalition of citizens in the Kansai region has made over 60 visits to cities evacuating and others which are evacuation points. We have learned there is no viable evacuation plan in place for the tens of thousands of people with special needs – inpatients and outpatient at hospitals and various facilities, those in day care, and those with handicaps living at home. When others can flee, there are no vehicles to transport these people nor medical care prepared if and when they reach the evacuation facilities. Restart of the Takahama plant is a human rights injustice toward children and those with handicaps.

"As for evacuation drills, Kansai Electric confirmed back in 2014 that Fukui Prefecture asked for the accident scenario to be sent from the utility to be for a small enough accident so the prefecture's evacuation drills could cope. All drills in the Fukui and northern Kyoto Prefecture region have been grossly inadequate. There is no consideration that there could be heavy snow or an earthquake.

"The government and Kansai Electric has ignored repeated calls by the 8 prefectures and 4 cities of the Union of Kansai Governments which state since they are in the region that can be affected by a serious accident, therefore they should have consent rights when it comes to reactor restart issues."

Green Action noted that the Takahama plant still lacks a seismic isolation emergency control room. Executive director Aileen Mioko Smith said: "Restart of Takahama violates the NRA seismic safety standard. Operating a Japanese reactor without a seismic isolation emergency control room is negligence in the extreme. Tens of thousands of children including babies and those with special needs not being protected under current emergency management planning is an outright human rights violation."6

Fire hazards

According to Greenpeace and Green Action Japan, representatives of the NRA admitted at a meeting held in the National Diet on 21 January 2016 that they do not know whether Takahama 3 and 4 reactors are in violation of their own fire safety regulations, in particular, the integrity of cabling.7

Safety-related cabling in a reactor must be separated to ensure that in the event of fire or other singular incident, critical redundant safety systems and power supplies are not lost. Kendra Ulrich from Greenpeace Japan said on January 26: "This latest example of complete negligence by the NRA just days before the Takahama unit 3 reactor is scheduled to restart is wholly unacceptable. It's like allowing an airliner packed with passengers to take off without knowing whether the fuel lines and the control wires are crossed. If an accident happens, the power and backup safety systems could be taken out at once, and the plane is going down."7

A coalition of NGO's have petitioned the NRA on a ranges of safety issues at Takahama, including safety cabling and earthquake risks. There are 14 petitioners including Green Action, Friends of the Earth, Greenpeace Japan, and numerous local NGOs.7

Broader regulatory problems

Some of the problems associated with the regulatory process for KEPCO's Takahama reactors were also seen with the Kyushu Sendai reactor restart process. There are overarching problems, neatly summarized last October by Prof. Yoshioka Hitoshi, a Kyushu University academic who served on the government's 2011– 12 Investigation Committee on the Accident at the Fukushima Nuclear Power Stations:2

"Unfortunately, the new regulatory regime is ... inadequate to ensure the safety of Japan's nuclear power facilities. The first problem is that the new safety standards on which the screening and inspection of facilities are to be based are simply too lax. While it is true that the new rules are based on international standards, the international standards themselves are predicated on the status quo. They have been set so as to be attainable by most of the reactors already in operation.

"In essence, the NRA made sure that all Japan's existing reactors would be able to meet the new standards with the help of affordable piecemeal modifications – back-fitting, in other words. In practice, they need only to add a new layer of emergency management and some back-up equipment to meet the new standards for emergency preparedness. The estimates for earthquake intensity and tsunami height in each locale have been revised upward, but not to the point where they would necessitate fundamental design changes.

"The second basic problem is that the new standards do not cover all the levels of "defense in depth" advocated by the International Atomic Energy Agency in its seven-stage International Nuclear Events Scale. They extend only as far as Level 4 ("control of severe conditions including prevention of accident progression and mitigation of the consequences of a severe accident"), stopping short of Level 5 requirements for responding to accidents that threaten the surrounding area through significant release of radioactive materials."


1. CNIC, Nuke Info Tokyo, No. 164, Jan./Feb. 2015, 'CNIC Public Comment on the Draft Report for the New Regulatory Requirements Screening for the Kansai Electric Power Company's Takahama Nuclear Power Plant',

2. Yoshioka Hitoshi, 23 Oct 2015, 'Time to Stop Nursing the Nuclear Power Industry',

3. 30 Jan 2016, 'Nuclear reactor restart inspires protest and support in Takahama',

4. Nuclear Engineering International, 2 Feb 2016, 'Japan's Takahama 3 begins power generation',

5. Eric Johnston, 29 Jan 2016, 'Third reactor restart spurs fears over shaky Kansai evacuation plans',

6. Green Action, 28 Jan 2016, 'Lessons of the Fukushima Nuclear Power Plant Have Not Been Learned',

7. Greenpeace and Green Action, 26 Jan 2016, 'Japan's Nuclear Regulator: We don't know if Takahama Reactor has significant fire safety violation',

A detailed briefing on the reactor cable separation problem is posted at: