CNIC Statement: We Protest the Granting of Consent to Operate the Aging Nuclear Power Plants, Takahama Unit 1 and Unit 2 and Mihama Unit 3, Beyond Their Lifespan of 40 Years
Citizens’ Nuclear Information Center (issued in Japanese on April 29, 2021)
On April 28, Fukui Prefecture Governor Sugimoto Tatsuji gave his consent to the operation of Kansai Electric Power Company’s (Kanden’s) Takahama No. 1, No. 2 and Mihama No. 3 reactors beyond their original 40-year lifespan. Governor Sugimoto’s consent was based on the premise that interim storage facilities would be located outside of the prefecture. However, Kanden’s plan to have a share in the facility located in Mutsu City, Aomori Prefecture, has been abandoned due to strong opposition from the city. The governor himself should therefore keep his pledge and withdraw his consent.
This is the first time in Japan that the government has agreed to operate a nuclear power plant beyond the 40-year lifespan, and there is a risk that this will become the norm in the future. We strongly protest the fact that the government has taken this initiative.
The risk of a severe nuclear accident increases with long-term operation. Much of the machinery and equipment will be replaced, but it is not possible to replace everything. For example, as some of the power cables cannot be replaced, the regulatory review allows the power company to get by with simply coating these cables with flame retardants. The most important piece of equipment that cannot be replaced is the reactor pressure vessel.
The pressure vessel is exposed to neutron radiation bombardment during operation, causing its properties as metallic material to degrade, resulting in brittleness. There is a risk that a pressure vessel in the process of brittle degradation will shatter instantly under rapid cooling, such as when the emergency core cooling system (ECCS) is activated. The three reactors in question have all become severely embrittled by neutron irradiation, and Takahama Unit 1 reactor in particular is known to have the most advanced brittle degradation and thus to be the most dangerous of all the reactors in Japan.
The shattering of the pressure vessel could lead to a radioactive disaster that would exceed that caused by the accident at the Fukushima Daiichi Nuclear Power Station. As the Mito District Court pointed out in the lawsuit to prevent the operation of the Tokai Daini Nuclear Power Station, the fact that the five-layer defense in depth system has not been incorporated into the regulations makes it clear that effective evacuation that avoids exposure to radiation is not possible. In some cases, the locations of evacuation stations are even in areas targeted for evacuation in the event of a disaster.
Above all, 10 years after the accident in 2011, the tragedy of the disaster is perfectly clear when we look at the health effects on those who have been exposed to radiation, the long period of life in evacuation, the emergence of difficult-to-return areas, and the loss of towns and villages.
Kanden is clearly incapable of taking responsibility for this disaster except through the bankruptcy of the company, and we strongly protest its decision to proceed with the operation of nuclear power plants exceeding the 40-year lifespan, prioritizing short-term management while failing to learn from the Fukushima nuclear accident. These decrepit NPPs should be decommissioned immediately.
Immediately prior to the granting of consent by Fukui Prefecture, the Ministry of Economy, Trade and Industry (METI) decided to grant an additional subsidy of up to 2.5 billion yen per power plant in return for Fukui Prefecture’s consent to extend operation beyond the 40-year limit. Such an approach will not lead to a revitalization of the region, but rather will only exhaust it, which in turn will only narrow the scope of government policy-making. We strongly oppose this outdated pork-barrel form of policy
