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10300 Millisievert per Hour in Fukushima Reactor No.1

28.06.2012

Susanne Gerber

The highest level of radiation to date has been detected inside the No.1 reactor vessel at the Fukushima Daiichi nuclear power plant. Tokyo Electric Power Company said it used endoscopes and dosimeters to examine the interior of the reactor on Tuesday. Internal measurements were made for the first time since the accident in March last year. The utility detected a record level of 10,300 millisieverts per hour. The measurement was taken 20 centimeters above the surface of a contaminated water puddle in the reactor’s suppression chamber. This high level of radiation would be fatal for humans within 50 minutes. No broken parts were identified in the containment vessel during the survey. 1,000 millisieverts per hour was detected about 4 meters above the water surface. The figure is 10 times higher than measured in the No.2 and No.3 reactors. Workers are expected to engage in clean-up and other tasks mostly at the 4-meter level, which is raising health concerns. TEPCO official Junichi Matsumoto said he suspects that a higher radiation level in the No. 1 reactor is caused by more fuel rods melting down than in other reactors. He said robots will be used for damage assessment because it is unsafe for humans to work on site.

http://www3.nhk.or.jp/daily/english/20120628_01.html

Einsortiert unter:Consequences, Fukushima, Meltdown, Radiation

91.2°C at Reactor No. 2

13.02.2012

Susanne Gerber


The temperature at the bottom of Reactor 2 RPV (69H1):

2/13 5:00 89.6
2/13 (missed the time, I think Matsumoto said 10:00) 91.2

It is not responding to the increased amount of water injected (about 18 tonnes/hour). The temperatures at the other two locations (69H2, 3) are going down. Therefore, it is the instrument failure most likely, TEPCO’s Matsumoto concludes. TEPCO will maintain the amount of water injected for the time being. No plan to change the amount for the time being. The steady rise of temperature like this doesn’t seem like instrument failure.
http://ex-skf.blogspot.com/2012/02/reactor-2-rpv-bottom-912-degrees.html

Einsortiert unter:Danger, Fukushima, Meltdown

All fuel has melted through, much of it into containment vessel… So where’s the rest? (VIDEO)

12.12.2011

Susanne Gerber

http://enenews.com/nhk-plant-operators-trying-to-find-nuclear-cores-all-fuel-has-melted-through-much-of-it-into-containment-vessel-so-wheres-the-rest-video

  • The fuel inside 3 reactors has melted through the bottoms of their furnaces
  • Plant operators try to identify where all the fuel has gone
  • Analysts estimate all of the fuel has melted through the furnace, much of it into the containment vessel
  • Above all, we need to know the temperature of the fuel
  • No thermometer is in place to let us know
  • Gov’t has set two conditions for declaring that the reactors are actually in cold shutdown
  • First is that the temperatures at the bottom of the reactors below 100°C
  • The other is to have greatly reduced emissions of radioactive substances
  • But if fuel has melted and reached the containment, the question arises as to the real significance of bottom temperatures of the tanks
  • The views of TEPCO is the fuel reactor was cooled. The company is indeed observed that the temperature in the containment is 40 degrees
  • The question is whether the people of Fukushima will be convinced by this argument
  • Another problem is that a temperature exceeding 100 degrees makes sense only when the vessel and the containment building were not damaged
  • The test loses its value when a reactor is damaged, which is the case at Fukushima Dai-ichi

Einsortiert unter:Accident, Consequences, Meltdown, Research

Leaks

Susanne Gerber

14.11.2011

At the No. 1, 2 and 3 reactors, melted nuclear fuel seems to be penetrating the pressure vessels and even leaking out from the reactor buildings.

The Unit 4 reactor building of the crippled Fukushima Dai-ichi nuclear power station is seen through a bus window in Okuma, Japan Saturday, Nov. 12, 2011. (AP Photo/David Guttenfelder, Pool)

The Unit 4 reactor building of the crippled Fukushima Dai-ichi nuclear power station, which has no nuclear fuel in the reactor itself, but about 1,535 fuel rods.

http://mdn.mainichi.jp/mdnnews/news/20111114p2a00m0na004000c.html

 

 

Einsortiert unter:Fukushima, Meltdown

Far Away From Any Stable Shutdown

Susanne Gerber

03.11.2011

“Some of the fuel has escaped the vessel, experts believe, and is in spaces underneath, where there is no way to use control rods to interrupt the flow of neutrons,” reports the New York Times. The Times reporters interviewed Hiroaki Koide, assistant professor at Kyoto University’s Research Reactor Institute:

  • “Mr. Koide holds that the nuclear fuel at the three reactors probably melted through containments and into the ground, raising the possibility of contaminated groundwater.”
  • “If much of the fuel was indeed in the ground early in the crisis, the “feed and bleed” strategy […] would not have done anything to reduce danger from fuel already in the soil…”

According to the Times, “Tokyo Electric does not deny the possibility that the fuel may have burrowed into the ground, but its officials say that ‘most’ of the fuel likely remains within the reactor, albeit slumped at the bottom in a molten mass.” The Times reported on another interview about the location of the fuel, this one with “a former nuclear engineer with three decades of experience at a major engineering firm… who has worked at all three nuclear power complexes operated by Tokyo Electric” who spoke on the condition of anonymity:

  • “His main concern was that officials could not pinpoint the exact location of the nuclear fuel — which would greatly complicate the cleanup.”
  • “He said that tiny fuel pellets could have been carried to different parts of the plant, like the spaces under the reactor during attempts to vent them in the early days. That would explain several cases of lethally high radiation readings found outside the reactor cores.”
  • “If the fuel has been dispersed more widely, then we are far from any stable shutdown.”

For more information on the melt-through see: Truth & Consequences: A guide to the triple melt-throughs at Fukushima (VIDEOS)

Einsortiert unter:Accident, Consequences, Fukushima, Kernschmelze, Meltdown

Xenon 133

Susanne Gerber

11.09.2011

The amount of radiation released during the Fukushima nuclear disaster was so high that the level of atmospheric radioactive aerosols in Washington state was 10 000 to 100 000 times higher than normal levels. The findings, published by a mechanical engineering professor at the Cockrell School of Engineering and researchers at Pacific Northwest National Laboratory (PNNL), provide important insight into the magnitude of the disaster. They also demonstrate huge advancements in the technology that’s used for monitoring nuclear material and detecting covert nuclear operations around the world. The material detected, Xenon, is of the same chemical family as helium and argon and is an inert gas, meaning it does not react with other chemicals. The gas  is not harmful in small doses and is used medically to study the flow of blood through the brain and the flow of air through the lungs. Xenon 133 is a nuclear fission product that is closely monitored at nuclear stations around the world because it can be used to determine whether a country has conducted an illegal or covert nuclear test explosion. Such tests are banned under the Comprehensive Nuclear-Test-Ban Treaty (CTBT), which was adopted by the United Nations in 1996 and created a worldwide network of nuclear monitoring stations. The detection of the radioactive gas in Washington is significant. „The culmination of international research collaborations resulted in this very sensitive monitoring technology. These advancements will not only be beneficial for nuclear monitoring, they are also very beneficial to the emergency response teams called to disasters like Fukushima,“ said Biegalski, an expert in nuclear forensics, nuclear modeling, and nuclear monitoring, who is currently developing complex algorithms that will be used to improve the capabilities even more. As soon as he and PNNL researchers began detecting radioactive gases in Washington, they shared the data with federal officials in the U.S. and Japan so that it could be relayed to emergency responders on the ground at Fukushima. „As the measurements came in sooner and at higher concentrations than we initially expected, we quickly came to the conclusion that there were some major core melts at those facilities,“ Biegalski said. The thought was confirmed by data collected by he and PNNL researchers. Their study reports that more radioxenon was released from the Fukushima facilities than in the 1979 meltdown at the Three Mile Island Nuclear Generating Station in Pennsylvania and in the 1986 Chernobyl nuclear disaster in the Ukraine.

The study was published in the Journal of Environmental Radioactivity.

Provided by University of Texas at Austin

 

Einsortiert unter:Fukushima, Meltdown, Research

動画で見る炉心溶融

Susanne Gerber

10.09.2011

http://www.youtube.com/watch?v=wwYk62WpV_s

 

Einsortiert unter:Fukushima, Kernschmelze, Meltdown

The Thought of an Uninhabited Tokyo

Susanne Gerber

07.09.2011

Former Japanese Prime Minister Kan Naoto says he felt a sense of crisis that the nuclear plant mishap in Fukushima could obliterate Tokyo and its vicinity, said the Japanese daily Tokyo Shimbun Tuesday. Kan, who stepped down as prime minister Friday, said, “The week shortly after the accident is the period when I felt the highest sense of crisis,” adding, “The thought of an uninhabited Tokyo made me shudder. At around 3 a.m. March 15, three days after the accident, I got a report from then Economy, Trade and Industry Minister Banri Kaieda that Tokyo Power Corp. was about to withdraw from the nuclear facility. So instantly I summoned the company`s president Masataka Shimizu and asked him to set up a joint countermeasures headquarters of the government and the company at the company’s headquarters,” Kan said. „Had Tokyo Power Corp. withdrawn from the nuclear power plant, nobody might live in Tokyo now. If the power company had pulled out of the facility and left nuclear fuel unattended, the cooling water would have dried out within dozens of hours and the meltdown of reactors would have occurred,” adding, “If this had been the case, radioactive materials several or even dozens of times as much as those leaked in Chernobyl would had leaked. The country was brought to the brink of collapse.” Kan also explained why he sought to wean Japan from nuclear energy, saying, “Before the accident, my stance was to utilize nuclear power plants. I thought that Japanese technology would make things all right but I changed my mind after the accident. If people cannot live within a radius of 100 or 200 kilometers from a crippled nuclear power plant, Japan will cease to exist. Evacuating 100,000 or 200,000 people is a very difficult task, but if we have to evacuate 30 million people in the capital area, we won`t have enough shelters to accommodate them. To avoid such a calamity, we have no choice but to become independent of nuclear power plants.” On communication of information at the time of the accident, Kan said, “Even the Prime Minister’s Office wasn’t informed of the situation accurately. The atomic safety commission said no hydrogen explosion would occur because containment vessels were filled with nitrogen. In reality, however, explosions occurred inside reactor buildings.”

http://english.donga.com/srv/service.php3?bicode=060000&biid=2011090715968

Einsortiert unter:Accident, Danger, Fukushima, Meltdown, Politics, Radiation, Reflection

Cesium-Resistant Rice

Susanne Gerber

23.08.2011

A research agency in Fukushima Prefecture has begun testing about 110 varieties of Japanese and foreign rice in a search for strains that absorb less radioactive cesium from the soil. The project, which was initiated by the Fukushima Agricultural Technology Center in Koriyama, after the meltdowns and explosions at the Fukushima No. 1 power plant, is unprecedented in that no research has ever been done on rice grown on land tainted by relatively high amounts of radioactive matter, the center’s research team said. The research is important since the radioactive fallout from the Tokyo Electric Power Co. plant will likely disrupt rice farming in nearby areas for years to come, it said. „We might be able to develop new (cesium-resistant) rice strains if we find rice varieties that absorb less cesium through this project and cross them with Japanese rice,“ said Keisuke Nemoto, professor at the University of Tokyo’s graduate school and a member of the team. The team is looking at a wide range of strains from South America, Africa and Asia, including India and Bangladesh. Last week, harvested rice from Ibaraki Prefecture was found to contain low levels of cesium for the first time since the nuclear crisis. One sample of brown rice from Hokota, about 150 km from the Fukushima No. 1 plant, had 52 becquerels per kilogram of cesium in preliminary tests. The central government’s provisional limit for cesium in grains is 500 becquerels per kg. The Fukushima Agricultural center detected some 3,700 becquerels per kg of cesium in soil on its property, which is close to the government-set limit of 5,000 becquerels per kg of cesium for soil to grow rice. In the past, Japanese researchers have studied the effects of radioactivity on rice cultivation based on data collected from nuclear weapons tests carried out by the United States and the former Soviet Union, the Agriculture, Forestry and Fisheries said.

No data are available, however, on rice grown on soil heavily contaminated with radioactive substances, the team said.

http://search.japantimes.co.jp/cgi-bin/nn20110823a3.html

Einsortiert unter:Fukushima, Meltdown, Radiation, Research

Heart-Warming to Know

Susanne Gerber

18.08.2011

According to Kevin Maher, a US diplomat and the former director of the Japan Desk at the US State Department in Japan, the US government considered evacuating all 90,000 US citizens in Tokyo right after the Fukushima I Nuclear Power Plant accident.

From Yomiuri Shinbun (10:30PM JST 8/17/2011):

東京電力福島第一原子力発電所の事故直後、米政府が、東京在住の米国人9万人全員を避難させる案を検討していたことが分かった。

The US government was considering the plan to evacuate all 90,000 US citizens living in Tokyo right after the Fukushima I Nuclear power Plant accident, according to a new book.

元米国務省日本部長のケビン・メア氏が、19日に出版する「決断できない日本」(文春新書)で明らかにした。9万人避難が実行されていれば、他国の政府対応はもとより、日本人にもパニックを引き起こしかねないところだった。

The book, which is to be published on August 17, is titled „決断できない日本 (Japan that cannot decide)“ (Bunshun Shinsho) and was written by Kevin Maher, former Japan Desk director at the US State Department. If the plan to evacuate 90,000 Americans had been carried out, it could have triggered reactions from other foreign governments, and caused panic among the Japanese.

メア氏は震災直後、国務省内の特別作業班で日本側との調整にあたり、著書にその内幕をつづった。

Maher’s book recounts the inside information that Maher obtained as he was part of the special task force within the State Department right after the March 11 disaster, communicating with the Japanese side.

米国人の避難が提起されたのは、3月16日未明(現地時間)の会議だった。米側は無人偵察機グローバルホークの情報から原子炉の温度が異常に高 いことを把握し、「燃料が既に溶融している」と判断。菅政権が対応を東電任せにしているとみて、「不信感は強烈」な状況だったという。米国人の避難を求め た政府高官に対し、メア氏らは「日米同盟が大きく揺らぐ事態になる」と反論し、実行に移さなかったとしている。

The subject of evacuating the US citizens was raised in the early hours on March 16 (local time). The US had already knew about the unusually high temperature of the reactors from the Global Hawk data, and determined that „the fuel has already melted“. The US thought the Kan administration was simply leaving the disaster response to TEPCO, and „distrust [in the administration] was intense“. The US high-ranking officials wanted to evacuate the US citizens [from Tokyo] but the local officials including Maher objected, as „it would severely undermine the US-Japan alliance“. The plan was never implemented.

It’s very heart-warming to know they left 90,000 US citizens in Tokyo under the radioactive plume, which literally rained on them on March 15, 16 and 21, for the sake of „alliance“, isn’t it?

I also remember back in March that the US investment bank Goldman Sachs flew in high-ranking executives to Tokyo, and told the US employees there in no uncertain terms that they were to stay put in Tokyo, or they would lose their jobs.

http://ex-skf.blogspot.com/2011/08/us-government-considered-evacuation-of.html

Einsortiert unter:Accident, Danger, Fukushima, Meltdown, Politics, Radiation, Research