December 14, 2012
It has been almost one year since Prime Minister Noda Yoshihiko declared an end to the Fukushima nuclear accident late last year, but the reality still falls far short of being brought “under control”.
Tokyo Electric Power Company on November 27 sent two robots into the No. 3 reactor building at the Fukushima plant and found that radiation doses inside had gone up to 4,780mSv/h. This amount is 3.7 times more than that measured one year ago and exceeds the acceptable radiation exposure for Fukushima plant workers just in one minute of exposure (up to 100mSv/y).
Exploring the premises for one hour and 40 minutes, the robots were exposed to 650mSv radiation. The results indicate the possibility that the level of contamination is increasing and that the condition inside is not safe for humans to tackle.
Tainted-water leakages are frequently occurring at the plant because of not only the initially damaged plumbing system but also human errors like cutting off pipes or opening valves by mistake.
Currently, 76,500 tons of highly radioactive water remain inside, only a 25% decrease from the 100,000 tons present when the disposal work began last June. Meanwhile, stored water containing radioactive materials and sea water amounts to 207,000 tons. Taking into account an increase in the amount of contaminated water that will be stored in the future, the existing tanks may be insufficient to store all the water.
Furthermore, the temperature inside the pressure vessels is still unknown because the explosions after the 3.11 quake destroyed many thermometers. Regarding the No. 2 reactor, it has 14 thermometers left intact out of the requisite 41. Only one thermometer is still operational at the bottom of the vessel to gauge if a cold shutdown is achieved.
The reality is showing that once a nuclear accident occurs, it will be extremely difficult to bring it under control.
Tokyo Electric Power Company on November 27 sent two robots into the No. 3 reactor building at the Fukushima plant and found that radiation doses inside had gone up to 4,780mSv/h. This amount is 3.7 times more than that measured one year ago and exceeds the acceptable radiation exposure for Fukushima plant workers just in one minute of exposure (up to 100mSv/y).
Exploring the premises for one hour and 40 minutes, the robots were exposed to 650mSv radiation. The results indicate the possibility that the level of contamination is increasing and that the condition inside is not safe for humans to tackle.
Tainted-water leakages are frequently occurring at the plant because of not only the initially damaged plumbing system but also human errors like cutting off pipes or opening valves by mistake.
Currently, 76,500 tons of highly radioactive water remain inside, only a 25% decrease from the 100,000 tons present when the disposal work began last June. Meanwhile, stored water containing radioactive materials and sea water amounts to 207,000 tons. Taking into account an increase in the amount of contaminated water that will be stored in the future, the existing tanks may be insufficient to store all the water.
Furthermore, the temperature inside the pressure vessels is still unknown because the explosions after the 3.11 quake destroyed many thermometers. Regarding the No. 2 reactor, it has 14 thermometers left intact out of the requisite 41. Only one thermometer is still operational at the bottom of the vessel to gauge if a cold shutdown is achieved.
The reality is showing that once a nuclear accident occurs, it will be extremely difficult to bring it under control.
