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2011年6月3日

Nuclear Power Plant? — Absolutely NO!! –It’s Not “Beyond Any Expectations”– By Tada Shigemasa

“You are in a panic, and the accident is beyond control, then say ‘No’ to nuclear power plants, absolutely!” demonstrators cried out to the deep and heavy tunes from the sound car in Koenji, Tokyo. On April 10, at Koenji Chuo Park, a protest rally against nuclear power plants was held, with the title, “Super-giant Anti-nuke Rock Festival cum Demo.” It was sponsored by “Shiroto no Ran (rebellion by amateurs),” a group that runs a recycle shop in the area.
The rally was held in the wake of the nuclear accident at Fukushima Daiichi Nuclear Power Plant (in Futaba-cho and Okuma-cho, Fukushima Prefecture) of Tokyo Electric Power Company (TEPCO), and many young people and families with children took part.
Mr. Yoshikawa Haruto (alias, age 27) learned about the rally through Twitter, where short comments were posted on the Internet. As he searched the cause of the accident, he learned that Hamaoka Nuclear Power Plant of Chubu Electric Power Company (Shizuoka Prefecture) was located right on the dangerous fault line. “I don’t think we can get rid of nuclear power plants all at once, but hope this rally would trigger the shift in policy for alternative energy,” Yoshikawa said.

All Electric Power Supplies were Lost
Why did the nuclear accident happen? It is said that immediately after the earthquake on March 11, Fukushima Daiichi NPP successfully brought the nuclear fission reaction to emergency shutdown. But even after the fission reaction is stopped, uranium fuel would continue to produce “decay heat” from radioactive materials, so it is necessary to keep cooling it down for a long period of time. However, the 14 to 15 meter-high tsunami hit the power plant directly, knocking down the transmission line tower (a tower supporting the power transmission lines from outside). After the emergency diesel generator was destroyed by the tsunami, all power supplies were lost.
Thus, the devices to pump water to the reactor core became inoperable and water evaporated. The uranium fuel rods were totally exposed and started to melt with its own heat. The steam pushed up the inner pressure of the reactor. Due to chemical reaction, the heat produced hydrogen, which caused the hydrogen explosions and fire, resulting in the damage of reactor containment vessel and building structure, and radiation leakage.
As it became impossible to cool the spent fuel also, not only the first to third reactors, but also the fourth reactor, which had been stopped for regular checkup, started to leak radiation. Even in the case of the “history’s worst” nuclear accident in Chernobyl (in former U.S.S.R., 1986), it was only one nuclear reactor that failed.

Nuclear Accident was a Human Disaster
Why was the accident not prevented? The government and TEPCO maintain that the scale of the tsunami was “beyond any expectations,” but it misrepresents the fact. Although they were repeatedly urged to plan for the worst, they had consistently ignored such warnings.
Now, the Diet interpellation by Yoshii Hidekatsu, the House of Representative Member (Japanese Communist Party) has come under spotlight. In the Budget Committee of the House of Representatives in March 2006, he pointed out the possible danger of hydrogen explosion and core meltdown at nuclear power plants, caused by “anaseism” of tsunami, as was the case in the recent great earthquake, which would destroy emergency power sources, or alternatively by “kataseism” (which would lower the seawater surface) which would make it impossible to take in the seawater to cool the water to be pumped into the reactor.
In the Economy, Trade and Industry Committee of the House of Representatives in May 2010, too, Mr. Yoshii sited the examples of the power transmission tower knocked down by the landslide (Hakui City, Ishikawa Prefecture, 2005) and the accident where all the backup power supplies were lost (Forsmark Nuclear Power Plant, Sweden, 2006) and warned the possibility of failure of all power sources in case of a giant earthquake. However, the government only replied, “Our safety design is so perfect that such a possibility is virtually inconceivable.” (Terasaka Nobuaki, Director of Nuclear and Industrial Safety Agency, May 2010)
But look now. The situation turned out exactly as he has pointed out. Tokyo Shimbun (March 24 issue), taking up Mr. Yoshii’s question of 2006, criticized TEPCO and the government overusing the word “beyond expectations”, saying, “It smells of covering up a human disaster.” Also, in the Economy, Trade and Industry Committee of the House of Representatives on April 6, Director Terasaka of Nuclear and Industrial Safety Agency had to admit at the interpellation by Mr. Yoshii, that he had lacked understanding when he replied to him in May 2010.

Government and TEPCO Refused to Learn Lessons from Past Accidents
Fukushima was not the first nuclear power plant accident. In Chuetsu-Oki Earthquake of 2007, an accident involving fire and radiation leak occurred at Kashiwazaki-Kariwa NPP of TEPCO. Although the reactor successfully came to an emergency halt and cooling system operated, radioactive material leaked in the air and the seawater. The seismometer at the basic infrastructure of the building covering the reactor recorded 680 Gals at the first reactor, and 606 Gals at the second reactor, but the designed value was only 450 Gals for each. The seismometer at the turbine generator pedestal of the third reactor recorded 2,058 Gals, 2.5 times of the designed value of 438 Gals. Literally, the shock was “beyond expectations.”
However, TEPCO, despite admitting there were 3,665 points in its power plant where accidents/disorders were caused by the earthquake, taking advantage of the fortunate fact that they did not lead to a large-scale accident, insisted, “the safety of the power plant was maintained.” And both the Nuclear and Industrial Safety Agency and the Nuclear Safety Commission confirmed this conclusion.
In the same year of Chuetsu-Oki Earthquake, the “Fukushima Network Seeking Safety of Nuclear Power Plants” questioned TEPCO, “What were the lessons drawn from Chuetsu-Oki Earthquake?” and urged that all 10 reactors at Fukushima Daiichi and Daini NPPs should be thoroughly checked.
Even after the accident at Fukushima Daiichi NPP, despite the criticism that it was a human disaster, TEPCO has kept on insisting, “The tsunami as high as 14-15 meters were beyond all expectations” (CEO Shimizu Masataka at the House of Councilors, April 18). Their continued denials of accepting responsibility can easily invite another accident.

It’s Not a Fantasy to Break Away from Nuclear Power
Besides resolving the critical situation at Fukushima Daiichi NPP urgently, it is now necessary to break away from the nuclear power-dependent energy policy.
It is essential to expand the use of renewable energy resources, including hydraulic, solar, wind, tidal, geo-thermal and bio-mass, not limited nonrenewables such as oil, coal, natural gas or uranium. Contrary to the nonrenewable energy sources, which have high-risk of causing far-reaching consequences once an accident happens, these renewable energy sources have relatively low-risk of causing accidents of great magnitude.
In Japan, nuclear power plants currently account for about 30% of total electricity generation. In Germany, already 16% of total electricity is produced by renewable energy sources, which is equivalent to 25 units of the first reactor at Fukushima Daiichi NPP.
Even in Japan, in Oita Prefecture, 25% of electricity generation is through renewable sources. Thus, breaking with nuclear power is not a fantasy. In Wakkanai City of Hokkaido, as much as 70% of total electricity generation is from wind power and other renewables.

Before Another Severe Accident Occurs
With the pretext of “countering global warming” or “reducing CO2,” the Japanese government, electric power companies and nuclear power manufacturers have promoted building more nuclear power plants.
In February this year, “Nuclear Renaissance Forum” was founded. Former Education Minister Arima Akito (Former President of the University of Tokyo) assumed the post of President, and the Forum includes as its members presidents of electric power companies such as TEPCO and Kansai Electric Power, the heads of such nuclear plant manufacturers as Toshiba, Hitachi and Mitsubishi Heavy Industries, and also the presidents of Nippon Steel Corp. and Toyota Motor Corp. The Forum upheld the promotion of export of nuclear power plants abroad and boasted, “Securing such orders by the joint effort of the public and private sectors is essential for the future growth strategy of the Japanese economy.”
Since 2008, teaching about nuclear power was officially included in the government guidelines for education, and the Ministry of Education and the Ministry of Economy, Trade and Industry jointly published a supplementary textbook for primary and junior-high school students, which stated, “Nuclear power plants are built so sturdy that they can withstand any large-scale earthquakes or tsunamis.” However, the fact they are neither safe or clean has been so evidently proved by the Fukushima disaster.
On April 15 in Germany, the Prime Minister Merkel and 15 state Premiers met and agreed to abolish all nuclear power plants at an early date. Here in Japan, it is high time for us to make a drastic change in our energy policy, while reviewing our lifestyles and 24-hour society, including how people work and how they are worked. And this change must be made before another severe accident occurs.

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