information about Fukushima published in English in Japanese media info publiée en anglais dans la presse japonaise
29 Mai 2015
May 29, 2015
http://ajw.asahi.com/article/0311disaster/fukushima/AJ201505290052
THE ASAHI SHIMBUN
The U.N. nuclear watchdog squarely puts the blame for the Fukushima nuclear crisis on the plant operator’s inadequate preparations against natural disasters and severe accidents.
Tokyo Electric Power Co. failed to carefully consider the risks of an earthquake and tsunami in advance, the International Atomic Energy Agency states in its latest report.
Although it had been estimated before the accident that a possible magnitude-8.3 quake off Fukushima would spawn a 15-meter tsunami, for example, TEPCO had not taken any steps to protect against such an event. In fact, the utility had estimated the highest possible tsunami at just 5.7 meters.
On March 11, 2011, towering tsunami waves measuring up to 15.5 meters smashed into the Fukushima No. 1 nuclear power plant following the magnitude-9.0 Great East Japan Earthquake.
The IAEA will hold a meeting in June on the report, which was compiled by about 180 experts from 42 countries. It is then expected to formally present the document to its members at its plenary session in September.
The report begins with IAEA Director-General Yukiya Amano pointing out TEPCO had insufficiently prepared for a major earthquake leading to a nuclear accident.
He also notes that some factors behind the nuclear crisis are not unique to Japan, and that learning lessons from the Fukushima crisis and patiently ironing out problems is the key to a better safety culture.
The report also criticizes the now-dissolved Nuclear and Industrial Safety Agency, which told TEPCO to take protective measures against a massive tsunami in the future and not immediately.
As the Fukushima crisis progressed, meltdowns occurred at the No. 1, No. 2 and No. 3 reactors at the plant. TEPCO had not considered a scenario in which the power supply and cooling functions would be lost simultaneously at more than one reactor, according to the report.
Also, while TEPCO had created a manual on how to respond to a severe accident, the company had not given workers proper training that would have enabled them to address the situation worsening over time. In addition, inadequate equipment was in place to deal with emergencies.
The report also lays into the Japanese government as its standards and policies in safety assessments and responses to severe accidents were at a lower level than in other countries.
And it says Japan had failed to formulate a plan to protect evacuating residents from radiation if a nuclear accident and a major natural disaster occurred simultaneously.
(This article was written by Toshio Kawada and Shunsuke Kimura.)
May 25, 2015
Kyodo
VIENNA – The International Atomic Energy Agency criticized Tokyo Electric Power Co. and Japanese regulatory authorities for their failure to prevent the 2011 Fukushima No. 1 nuclear plant disaster despite knowing the risk of large tsunami hitting the facility, according to a copy of an IAEA report.
The U.N. nuclear watchdog said in the final report on the nuclear disaster triggered by a huge earthquake and tsunami in March 2011, obtained Sunday, that “the Fukushima Daiichi NPP (nuclear power plant) had some weaknesses which were not fully evaluated by a probabilistic safety assessment, as recommended by the IAEA safety standards.”
The paper, compiled by around 180 experts from 42 countries, is set to be submitted to the IAEA’s annual meeting in September after its board examines the 240-page summary in June.
The report addressing the causes and consequences of the Fukushima disaster as well as lessons learned is expected to serve as a reference for nuclear safety measures worldwide.
The IAEA said a new approach applied between 2007 and 2009 postulated a magnitude-8.3 quake off the coast of Fukushima that could lead to tsunami of around 15 meters hitting the No. 1 plant and inundating the main buildings.
Despite the analysis, Tepco, the old Nuclear and Industrial Safety Agency, which oversaw Japan’s nuclear industry at that time, and other organizations did not act, deciding instead that “further studies and investigations were needed.”
“Tepco did not take interim compensatory measures in response to these increased estimates of tsunami height, nor did NISA require Tepco to act promptly on these results,” the report says.
Prior to the accident, there was not sufficient consideration of low probability, high consequence external events which remained undetected. This was in part because of the basic assumption in Japan, reinforced over many decades, that the robustness of the technical design of the nuclear plants would provide sufficient protection against postulated risks,” it says.
As a result, Tepco did not implement a sufficient safety assessment as recommended by the IAEA and lacked protection for the emergency diesel generators, battery rooms and other vital systems against tsunami-caused flooding, the paper adds.
“The operators were not fully prepared for the multiunit loss of power and the loss of cooling caused by the tsunami. Although Tepco had developed severe accident management guidelines, they did not cover such an unlikely combination of events,” the report says, also pointing to the lack of appropriate training for workers at the plant.
The IAEA called on countries that use, or plan to use, nuclear power to make continuous efforts to improve safety based on new findings and to be prepared to cope with natural disasters more severe than those predicted when nuclear power plants were designed.
“There can be no grounds for complacency about nuclear safety in any country. Some of the factors that contributed to the Fukushima Daiichi accident were not unique to Japan,” the report warns.
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