Nreactor

Japan Press Service Co., Ltd. is the only news agency providing information of progressive, democratic movements in Japan

Tsunamis may prohibit cooling of Japan's N-reactors: JCP Dietmember reveals

In the event that tsunami undertows decrease the sea level by five meters, 43 nuclear reactors (about 80 percent) in Japan will face thr danger of being unable to utilize seawater for cooling, making core meltdown a possibility.

Japanese Communist Party representative Yoshii Hidekatsu on March 1 revealed this possibility at a House of Representatives Budget Committee workshop.

Yoshii said that in the 1960 Chilean Tsunami, a backrush of water continued for about 25 minutes in the Sanriku Coast on the Pacific, northern Japan, and it is estimated that the sea level fell by six meters in Onagawa Town in Miyagi Prefecture where a nuclear power plant is now located. He pointed out that these data indicate that water used as coolant for nuclear plants cannot be taken from the sea if the water level falls.

Nuclear and Industrial Safety Agency Director General Hirose Kenkichi admitted that if the sea level falls by four meters, 28 nuclear plants (five meters for 43 plants, six meters for 44 plants) will temporarily be unable to take in sea water.

Citing the Hamaoka Nuclear Power Station No.1 reactor in Omaezaki City in Shizuoka Prefecture as an example, JCP Yoshii pointed out that it will take only 34 seconds to become unable to cool down the reactor after the stoppage of water intake, and that 60 tons of coolant water per minute will be necessary to eliminate radioactive decay heat even after the reactor is shut down.

Yoshii said, "We should assume the worst case scenario such as core meltdown and water vapor eruption that can occur if decay heat cannot be properly removed," and demanded that the government take appropriate measures against such accidents.

Minister of Economy, Trade and Industry Nikai Toshihiro promised to make efforts to solve the problem in order to secure safety.
- Akahata, March 2, 2006