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interesting Reuters story that indicates Fukushima had warning signs.
http://graphics.thomsonreuters.com/11/07/JapanNuclearRadiation.pdf
http://graphics.thomsonreuters.com/11/07/JapanNuclearRadiation.pdf
NUCENG said:interesting Reuters story that indicates Fukushima had warning signs.
http://graphics.thomsonreuters.com/11/07/JapanNuclearRadiation.pdf
swl said:How could this be considered a warning of the Fukushima disaster?
NUCENG said:...
In a short 5 page story, Reuters has pointed out a TEPCO culture of cost over safety, regulatory collusion and neglect. They wrote this in a factual style without a lot of fear-mongering, but didn't pull any punches either. That is one of the better reports I have seen.
NUCENG said:...First, keeping worker dose ALARA is a key indicator in safety conscious work environments.
From the Reuters story (p1):
“For five years to 2008, the Fukushima plant was rated the most hazardous nuclear facility in Japan for worker exposure to radiation and one of the five worst nuclear plants in the world on that basis.”...
The article is a bit sensational and misleading in terms of 'dangerous'. It's comparing particular plants to the global fleet. Someone has to be on the top in terms of expsoure, but that doesn't mean that the environment is necessarily dangerous. Generally, exposure at plants is well below industry safety standards, but certainly above levels that one would find outside the plant. Those rankings reflect those particular plants cited. All facilities strive to reduce exposure to employees, and some do a better job than others.swl said:So, the Perry, OH BWR is the most dangerous plant in the world? <doubting>
Would that indicate anything regarding the state of nuclear safety in the USA, or Ohio?
swl said:Thank you for explaining http://graphics.thomsonreuters.com/11/07/JapanNuclearRadiation.pdf" .
So if I take a look at their list (top p3) of the "five worst plants in the world", what should I think about the number 1 worst plant in the world being the Perry, Ohio BWR?
So, the Perry, OH BWR is the most dangerous plant in the world? <doubting>
Would that indicate anything regarding the state of nuclear safety in the USA, or Ohio?
The Nuclear and Industrial Safety Agency said the operator informed it just four days before Japan's massive March 11 earthquake and tsunami that waves exceeding 10 meters (33 feet) could hit the Fukushima Dai-ichi nuclear plant.
[...]
In 2009, TEPCO notified NISA of a separate calculation showing that a six-meter (20-foot) tsunami could hit the plant, based on studies of a tsunami that occurred in the year 869.
http://mdn.mainichi.jp/mdnnews/news/20110825p2g00m0dm050000c.html
TEPCO says it didn't mean to disclose the assessment since it was a tentative calculation for research purposes based on a simulation.
http://www3.nhk.or.jp/daily/english/24_36.html
At the 32nd Joint Working Group for Earthquake, Tsunami, Geology, and Foundations
under the Seismic and Structural Design Subcommittee (June 24, 2009) held in order to
conduct examination related to earthquake, it was pointed out that although the
investigation report about tsunami by the Jogan earthquake in 869 was made by National
Institute of Advanced Industrial Science and Technology and Tohoku University, the
earthquake causing the tsunami was not dealt with. Regarding this, NISA requested
TEPCO at the 33rd Joint Working Group (July 13, 2009) to take into account the Jogan
earthquake for evaluating design tsunami height when new knowledge on the tsunami of
the Jogan earthquake is obtained.
III-31 http://www.kantei.go.jp/foreign/kan/topics/201106/pdf/chapter_iii-2.pdf
Over the past two weeks, Japanese government officials and Tokyo Electric Power executives have repeatedly described the deadly combination of the most powerful quake in Japan’s history and the massive tsunami that followed as “soteigai,” or beyond expectations.
(...)
The tsunami research presented by a Tokyo Electric team led by Toshiaki Sakai came on the first day of a three-day conference in July 2007 [2006 (1)] organized by the International Conference on Nuclear Engineering [in Miami].
(...)
Sakai's team determined the Fukushima plant was dead certain to be hit by a tsunami of one or two meters in a 50-year period. They put the risk of a wave of 6 meters or more at around 10 percent over the same time span.
http://www.reuters.com/article/2011/03/29/us-japa-nuclear-risks-idUSTRE72S2UA20110329
It is meaningful for tsunami assessment to evaluate phenomena beyond the design basis. Because once we set the design basis tsunami height, we still have possibilities tsunami height exceeds the determined design tsunami height due to uncertainties regarding the tsunami phenomena. It is apparent that probabilistic risk assessment (PRA) gives us an effective clue. PRA is enlarging its usage for seismic design, but rarely used for tsunami risk evaluation due to its underdevelopment.
Sakai et al. Abstract available by clicking "expand all sessions in track" after "TRK 6 Safety and Security" and then the "ICONE14-89183 Development of a Method for Probabilistic Tsunami Hazard Analysis in Japan" link below "Monday, July 17, 2006 10:30 AM-12:30 PM" at http://archive.asmeconferences.org/ICONE14/TechnicalProgramOverview.cfm
tsutsuji said:Why wasn't this story told in the Japanese government's report to IAEA in June ? The tsunami safety design story in that report ends with
Was Mr Makoto Takao of Tepco aware of the "over 10 m" estimate when he presented his O.P. + 5.7 tsunami, "we assessed and confirmed the safety of the nuclear plants" http://www.jnes.go.jp/seismic-symposium10/presentationdata/3_sessionB/B-11.pdf page 14 slide at the November 24-26, 2010 Kashiwazaki international symposium on seismic safety of nuclear installations (http://www.jnes.go.jp/seismic-symposium10/presentationdata/content.html ) ? Isn't this kind of symposium a place where people are supposed to talk about the latest available research ?
http://www.jiji.com/jc/c?g=soc_30&k=2011082500390 On 25 August, Junichi Matsumoto insisted that Tepco's earlier comment that the March 11 tsunami is beyond expectations/assumptions ("想定外" sotei-gai) is not a problem. "I want to consistently maintain that it was a trial calculation. It was not something that could cause a change in the design assumptions (想定 sotei)". When the Earthquake Research Promotion Division of the government announced in July 2002 the probability of an earthquake off the coast of the Boso Peninsula and off the coast of Sanriku, Tepco made a trial calculation based on the hypothesis of an earthquake of the same level as the 1896 Meiji Sanriku earthquake occurring off the Fukushima coast, concluding that there is a risk that tsunami might surge with a maximum of 15.7 meters. The trial calculation assuming an earthquake of the same level as the 869 Jogan earthquake concluded with the possibility of a maximum of 9.2 meters. After receiving these results, Tepco asked the Society of Civil Engineers to revise the tsunami evaluation criteria, and at that time the officers in charge of nuclear power in the top management knew about these estimates. Former president Masataka Shimizu learned about them after the disaster at the latest.
29 March Reuters :
The research disclosed yesterday is different from the one presented in Miami in 2007, as it was made in the Autumn of 2008, according to http://www.yomiuri.co.jp/dy/national/T110824005905.htm
NUCENG said:During the earthquake design review following the Kashiwazaki Karawa earthquake the issue came up about the tsunami in 869. See the referenced article in post #125
NUCENG said:Found this about evaluation of tsunami and earthquake at Fukushima:
http://msquair.wordpress.com/2011/04/28/common-cause-at-daiichi-fukushima/
The Daiichi panel wrapped up its review and, on June 24, 2009, presented its findings to a larger working group of 40, which included just two tsunami experts.
http://www.washingtonpost.com/world...t-of-tsunami/2011/03/22/AB7Rf2KB_story_1.html
tsutsuji said:Thank you.
That March 28 blog page refers to a "2011/03/22" URL, "Published: March 24" Washington Post article:
which is not very different from what is said page III-31 of http://www.kantei.go.jp/foreign/kan/...pter_iii-2.pdf and where we understand that some non-Tepco people like seismologist Yukinobu Okamura raised the 869 tsunami issue. What we learn from the 29 March Reuters news and from the 24 August NISA announcement is that Tepco had developed research internally on the tsunami issue which concluded that the risk existed with some non-negligible probability. We can no longer summarise the story by saying that while some non-Tepco people were aware of the risk, Tepco was unaware of the risk or dismissing the claims: the blogger, Matthew Squair, talks about "symptoms of a collective view or ‘groupthink‘ that denied the possibility of a hazard to the plant from a tsunami event". The story seems now to be more complicated than that.
http://www3.nhk.or.jp/news/genpatsu-fukushima/20110825/0430_iaea.html Tepco vice-president Ichiro Takekuro was communicated the above 10 metres tsunami assessment results at the time when a study was commissioned to the Society of Civil Engineers. Junichi Matsumoto said: "The estimate was a calculation resulting from an accumulation of hypotheses, therefore it had no concrete basis, which is why we did not publicly release it". Yoshinori Moriyama, senior NISA official in charge of measures against nuclear disasters [the NISA spokesman in Fukushima Daiichi press conferences], said: "Even if it is a trial calculation, it constitutes material for [safety] evaluation. Tepco should have reported it early. In hindsight, I think the tsunami countermeasures were not sufficient".
http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_110825_01-e.pdf Tepco press release with a time-line of tsunami research from H14.2 (February 2002) to H23.3 (March 2011). [It includes the Toshiaki Sakai presentation at the ICONE-14 Miami conference in 2006, but it is not saying a word about Makoto Takao's presentation at the November 24-26, 2010 Kashiwazaki international symposium]
I found the links to the following research papers :
* Sawai et al. (2008) : "Marine incursions of the past 1500 years and evidence of tsunamis at Suijin-numa, a coastal lake facing the Japan Trench" The Holocene 18,4 (2008) pp. 517–528 http://www.fsl.orst.edu/wpg/events/S11/Sawai et al 2008 .pdf (in English)
* Satake et al. (2008) : "Numerical simulation of the AD 869 Jogan tsunami in Ishinomaki and Sendai plains" by Kenji Satake, Yuichi Namegaya and Shigeru Yamaki, Annual Report on Active Fault and Paleoearthquake Researches, 8, 71-89, 2008 http://unit.aist.go.jp/actfault-eq/seika/h19seika/pdf/03.satake.pdf (in Japanese, with English abstract and English translations of figure captions).
* Namegaya et al. (2010) : "Numerical simulation of the AD 869 Jogan tsunami in Ishinomaki and Sendai plains and Ukedo river-mouth lowland" by Yuichi Namegaya, Kenji Satake, and Shigeru Yamaki, Annual Report on Active Fault and Paleoearthquake Researches, 10, 1-21, 2010 : http://unit.aist.go.jp/actfault-eq/seika/h21seika/pdf/namegaya.pdf (in Japanese, with English abstract and English translations of figure captions).
Most recently, it was revealed that NISA, the nuclear watchdog, asked utilities to stage supportive questions at a METI-hosted symposium on the controversial use of plutonium-uranium mixed oxide (MOX) fuel in an apparent attempt to manipulate public opinion in favor of nuclear power.
http://search.japantimes.co.jp/cgi-bin/nn20110804x1.html
Chubu Electric Power Co. and Shikoku Electric Power Co. said they were ordered to do so by the Nuclear and Industrial Safety Agency, ostensibly the government's chief nuclear watchdog. Economy, Trade and Industry Minister Banri Kaieda, who oversees the agency, admitted to, and apologized for, those actions by officials. At a parliamentary hearing where he was berated by opposition lawmakers for his handling of the mushrooming scandal, Mr. Kaieda broke down in tears.
The disclosures prompted Prime Minister Naoto Kan last week to label NISA a "lobby" of the utilities, and spurred the government to propose breaking up NISA by removing its nuclear industry oversight responsibilities and handing them over to the environment ministry.
http://online.wsj.com/article/SB10001424053111904823804576499942442007306.html
tsutsuji said:Yoshinori Moriyama explained that, as they are not based on real facts, they were provided to the Kantei only as a reference/footnote. The 11 March around 10 PM data predicted fuel damage 2 hours later, meltdown 3 hours later, and the necessity to perform venting with radiation release at 3:20 AM, 12 March.
That the information about the core status was not released until mid-May, is highly deplorable, he [a former head of American Nuclear Society] says. Everybody in Japan feels the same.
(...)
He says the meltdown of units 1 ~ 3 could be predicted out of a simple heat balance, and it was supported by the evidence of radioactive substance releases, so he felt considerable despair over the fact that although considerable damage had been done to the citizens, Tokyo Electric and the public authorities admitted meltdown for the first time two months after the accident. To stretch it a little, the citizen's confidence has been betrayed, and this could be an important factor damaging the use of nuclear energy in Japan in the future, he warns.
Hisashi Ninokata, "The Reception of the Fukushima nuclear power plant accident by the ANS: How key members of the ANS perceived accident information", ATOMOΣ, vol. 53 No.9 (September 2011) p.602.
http://www.aesj.or.jp/atomos/tachiyomi/2011-09mokuji.pdf (my translation)
tsutsuji said:http://www.yomiuri.co.jp/dy/national/T110906004963.htm "Kan revealed that the off-site emergency response center near the plant, though supposed to serve as a front-line command center in the event of a crisis, was vacated soon after the accident" (...) Kan: "All the crisis-management arrangements that had been made prior to the accident failed to function properly."
http://mdn.mainichi.jp/mdnnews/news/20110908p2a00m0na022000c.html "TEPCO submits heavily redacted copy of Fukushima nuke accident manual"
zapperzero said:We knew that already. Everyone left as it appeared that Unit 1 was ready to blow, but they returned later.
In relation with the Local Nuclear Emergency Response Headquarters, since the accident events rapidly proceeded in a situation where communication with the Off-site center was difficult due to the disaster, the initial collection of information and communication were conducted mainly by ERC.
(...)
As preparation for earthquakes and tsunamis, etc. in power supplies, communication and reserves, etc. was not sufficient at the Off-site Center (OFC) where the Local Nuclear Emergency Response Headquarters was set up, and also, as enough information on the plant was not obtained as an external factor, expected function of information gathering and communication was not performed from the beginning.
(...)
Meanwhile, convening related parties and dispatching them to the site planned in the framework of the Act on Special Measures Concerning Nuclear Emergency Preparedness was also insufficient in the initial startup stage. This was partly because advanced notices and the register of members to be convened was not fully performed and is to be improved. There is also a background factor that many of current members are planned to be convened from a long distance and improvement should be made for realistic response to a case in which a disaster event proceeds rapidly as in this time.
This time it is contemplated that OFC failed to effectively function under such combined conditions leading to a delay in full-fledged operation of the Local Nuclear Emergency Response Headquarters.
Pages V-42, V-43 http://www.kantei.go.jp/foreign/kan/topics/201106/pdf/chapter_v.pdf (my boldening added)
See also page V-4 : "Plant information, ERSS, SPEEDI and others were still unavailable at the Off-site Center for some period of time"
zapperzero said:We knew that already. Everyone left as it appeared that Unit 1 was ready to blow, but they returned later.
As in, 90% or more is blanked out.
According to the legislation enacted Friday, the new panel will be open to the press,
(...)
The government panel, meanwhile, is not open to the media.
http://search.japantimes.co.jp/cgi-bin/nn20111001a5.html
tsutsuji said:The Nuclear and Industrial Safety Agency said the operator informed it just four days before Japan's massive March 11 earthquake and tsunami that waves exceeding 10 meters (33 feet) could hit the Fukushima Dai-ichi nuclear plant.
[...]
In 2009, TEPCO notified NISA of a separate calculation showing that a six-meter (20-foot) tsunami could hit the plant, based on studies of a tsunami that occurred in the year 869.
http://mdn.mainichi.jp/mdnnews/news/20110825p2g00m0dm050000c.htmlTEPCO says it didn't mean to disclose the assessment since it was a tentative calculation for research purposes based on a simulation.
http://www3.nhk.or.jp/daily/english/24_36.html
tsutsuji said:http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_110825_01-e.pdf Tepco press release with a time-line of tsunami research from H14.2 (February 2002) to H23.3 (March 2011).
tsutsuji said:...
http://www.asahi.com/national/update/0918/TKY201109180217.html (18 September) The Atomic Energy Society of Japan has just created a draft probabilistic tsunami safety evaluation manual. Until now, there was a probabilistic manual for earthquakes, but not for tsunamis. Tsunami safety was relying on the standards of the Japanese Civil Engineering Society published in 2002, but in the present accident, those were largely exceeded, the emergency diesel generators were flooded, reactor cooling became impossible, and large amounts of radioactive substances were released. In response, the Atomic Energy Society of Japan decided in May to create a probabilistic tsunami safety evaluation manual. In the draft, tsunami heights and frequencies are predicted using data such as tsunamis of the past and active faults' sizes. The manual provides a method to calculate for each tsunami wave height, the probability of seawater flooding, of building and pipe damages caused by shocks of floating objects. It provides a method to calculate scenarios and related frequencies as regards the accumulation of failures and damages of every equipment leading to core damage. The purpose is to find out which equipment changes or reinforcements can lower the accident probability and to use these results in real safety countermeasures.
gmax137 said:tsutsuji, can you find a link to the actual draft document? All I can find is the story that the draft was created. I'd like to see the actual draft. Thanks
Unfortunately, such revelations come after the fact.Hisashi Ninokata, a professor with the Tokyo Institute of Technology, said, "A myth that nuclear plants were completely safe took on a life of its own and delayed efforts to improve their safety. We experts, too, were overconfident that a nuclear disaster of such magnitude would never happen."
. . . .
One audience member asked, "Does it take a disaster like this to make you notice problems?" In reply, Hosei University visiting professor Hiroshi Miyano said, "We need to reflect on our lack of imagination (regarding possible dangers to nuclear plants)."
Osaka University professor Akira Yamaguchi said, "I think we were in an environment that did not encourage us to exercise our imaginations."
. . . .
Astronuc said:...Osaka University professor Akira Yamaguchi said, "I think we were in an environment that did not encourage us to exercise our imaginations."
Unfortunately, such revelations come after the fact.
Folks (e.g. US NRC) are already looking at beyond design basis events (BDBE), but I see that the goal posts are starting to move - which is a good thing.gmax137 said:We in the nuclear industry must aspire to exercise our imaginations, and I hope we don't all focus on earthquakes, tsunamis, and SBO -- we need to take this lesson and apply it to all areas of analysis and operations -- we must question and re-question our assumptions and the validity of all our design bases. The same sneaky complacency can exist in areas completely unrelated to natural events.
rmattila said:Examples of the things that are currently being studied in the aftermath of the Fukushima accident can be found in the http://www.stuk.fi/ydinturvallisuus/ajankohtaista_ydinturvallisuus/ajankohtaiset_uutinen/fi_FI/uutinen_15092011/_files/86251419958379456/default/eu-stress-tests-national-progress-report-finland.pdf concerning the European "stress tests". The final results are to be expected by the end of the year.