Based on an article taken from www.Spiegel.de on 03/17/11, fundamental errors were made during the construction planning stage of the nuclear power plant Fukushima Daiichi. An engineer who was involved in the construction of the plant, Shiro Qgura, said that at the beginning of the construction of reactor 1 in 1967, the construction design based on the US company General Electric were used.
Although the location on the sandy coast line in the northeast of Japan is an earthquake prone area close to the ocean and is apparently different than the location of the US nuclear power plants, neither reactors nor safety systems were planned involving a possible tsunami. Despite the differences, the construction design was almost identical to the US plants. Ogura said that the danger of tsunamis was not at all taken into consideration. Ogura was involved in designing the cooling systems for all reactors except the fourth, according to the Japanese newspaper “Hokkaido”. Oguro said that that they were close to being ignorant, and that they did not ensure that the safety systems were sufficient.
The retired engineer emphasized the Japanese lack of experience in regards to nuclear technology during that time. He said that during the construction/design of reactor #1 they had no experience. They knew that the location was in the danger zone of earthquakes and tsunamis but that they were not able to take these dangers into consideration.
During the construction of the second reactor the design of GE was improved. However, apparently it was not enough. Oruga continued: “At that time we were told that in this area there was no danger of earthquakes stronger than 8 on the Richter scale”. During the following decades these statements were not revised. Shortly before his retirement the systems had been reviewed in regards to earthquakes but a strong earthquake as the recent one was not considered. “I feel responsible”, Oruga said in regards to the nuclear catastrophe.
Engineer Masashi Goto, who was also a previous employee of Toshiba, said that the catastrophe of the past days have shown that besides the power supply other safety systems were insufficiently planed for an emergency. The containment which houses the reactor pressure container was only rated for 50% of the pressure which actually occurred after the event. In addition he believes that the diameter of the pipes which have been used in the past days to release the steam from the containment might be too small. Multiple safety systems which should have been installed independently of each other were insufficient. When the pumps ceased to function due to the failure of the emergency power supply, replacement systems had been used which were designed for fire protection but not for the cooling of nuclear reactors.
Meike Patten, MPSafetyTraining
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