Mr. Yasuhisa Komoda
Director-General
Nuclear and Industrial Safety Agency
Professor Haruki Madarame is unsuitable to chair the committee studying the impact of the Chuetsu Oki Earthquake on the Kashiwazaki-Kariwa nuclear power plant.
We therefore demand that he be replaced.
Yukio Yamaguchi, Baku Nishio, Hideyuki Ban
Co-Directors of Citizens' Nuclear Information Center
(Japanese version faxed to Nuclear Industrial and Safety Commission on 31 July 2007)
The victims of the July 16 Chuetsu Oki Earthquake are living in a state of great anxiety after being forced to evacuate to emergency shelters. In addition, they are very worried about the Kashiwazaki-Kariwa nuclear power plant. According to news reports, survey results show that the nuclear power plant is the number one cause of their anxiety. These results are backed up by the fact that some parents gave their children iodine tablets and also by the fact that people are saying that they do not trust Tokyo Electric Power Company's (TEPCO) announcements.
During our visit to the nuclear power plant, we saw that roads had been deformed into wave shapes. We also saw where roads had subsided, or where such subsidence had been repaired. Almost the whole circumference of the water filter tank in front of unit 6 (1,000 kilo liters) was buckled.
The documents released by TEPCO also show that the damage to the Kashiwazaki-Kariwa nuclear power plant was enormous. The coupling in the drive axis of the unit 6 reactor building ceiling crane was broken. There was variation between the different units, but the S2 peak ground acceleration1 (measured at the base mat) was exceeded for all units. A figure of 680 Gal, which is 2.5 times larger than S2, was recorded for unit 1. Furthermore, among the maximum acceleration spectrographs announced by TEPCO on July 30, the recording for the first floor (pedestal) of the unit 1 turbine building was seven times the design limit, while a figure of 2058 Gal (2.5 times the design limit) was recorded for unit 3.
The local people do not want this nuclear power plant, which has been shaken beyond expectations, to be restarted ever again.
In this context, the Nuclear Industrial and Safety Agency (NISA) established a committee to carry out a study and respond to the impact of the Chuetsu Oki Earthquake on the Kashiwazaki-Kariwa nuclear power plant (the Committee). The Committee is "to study the facts regarding the specific effects" and to report on the "issues and responses for the government and the operator". Professor Haruki Madarame was chosen to lead the Committee, which has 20 members and held its first meeting on July 31.
NISA's role is to ensure the safety of nuclear power. This means that in circumstances where safety cannot be assured, NISA must require that steps be taken to increase earthquake resistance and when safety still cannot be assured, it must require that reactors be closed down.
However, Professor Madarame was quick to state that safety of [the Kashiwazaki-Kariwa nuclear power plant] was assured, saying that it is not a major problem if B and C class equipment breaks as a result of shaking in excess of expectations, as long as A class equipment maintains plant safety without breaking2. He has also repeatedly stated that he predicts that the plant will be able to restart in one to two years. We question the academic ethics of someone who makes such a statement before the inside of the reactor containment vessel has even been looked at. When the Committee's chairperson makes such comments, it is not possible to avoid the criticism that the study and response of the Committee itself will only be perfunctory.
It goes without saying that the shaking from this earthquake greatly exceeded the S1 "elastic deformation" limit. In fact, the shaking that was recorded also greatly exceeded the S2 "plastic deformation" limit3. Even if no effects are seen on the outside, there are bound to be safety risks lurking in every corner. The biggest issue is how to find these, for they must all be found. It is therefore outrageous that the chairman of the Committee has pronounced the plant safe before the investigation even begins.
For the above stated reasons, Professor Madarame is unsuitable to chair this Committee and we demand that he be replaced.
(Professor Madarame has a history of inappropriate comments. Examples of such comments are available in Japanese on request.)
Yukio Yamaguchi, Baku Nishio, Hideyuki Ban
Co-Directors of Citizens' Nuclear Information Center
1. Under Japan's old earthquake resistance guidelines, the design basis for nuclear power plants assumed a "maximum design earthquake" (S1) and an "extreme design earthquake" (S2), where S2 is greater than S1.
2. Equipment and facilities at nuclear power plants are divided into categories depending on their importance for nuclear safety. Class A equipment and facilities are considered to be most important.
3. Nuclear power plants are supposed to be designed so that deformation of safety important equipment and facilities caused by S1 strength shakes is elastic (i.e. they return to their original condition), whereas deformation caused be S2 strength shakes may be plastic (i.e. while they might not return to their original condition, they are still able to contain radioactive material).
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