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Fukushima all info here, ここ福島県のすべての情報

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The Fukushima Daiichi nuclear disaster (福島第一原子力発電所事故

The plant comprises six separate boiling water reactors originally designed by General Electric (GE), and maintained by the Tokyo Electric Power Company (TEPCO). At the time of the quake, Reactor 4 had been de-fuelled while 5 and 6 were in cold shutdown for planned maintenance.
 The remaining reactors shut down automatically after the earthquake, and emergency generators came online to control electronics and coolant systems. The tsunami broke the reactors' connection to the power grid and also resulted in flooding of the rooms containing the emergency generators. Consequently those generators ceased working and the pumps that circulate coolant water in the reactor ceased to work, causing the reactors to begin to overheat. The flooding and earthquake damage hindered external assistance.
In the hours and days that followed, reactors 1, 2 and 3 experienced full meltdown. As workers struggled to cool and shut down the reactors, several hydrogen explosions occurred. The government ordered that seawater be used to attempt to cool the reactors—this had the effect of ruining the reactors entirely.  As the water levels in the fuel rods pools dropped, they began to overheat. Fears of radioactivity releases led to a 20 km (12 mi)-radius evacuation around the plant, while workers suffered radiation exposure and were temporarily evacuated at various times. Electrical power was slowly restored for some of the reactors, allowing for automated cooling.
Japanese officials initially assessed the accident as Level 4 on the International Nuclear Event Scale (INES) despite the views of other international agencies that it should be higher. The level was successively raised to 5 and eventually to 7, the maximum scale value. The Japanese government estimates the total amount of radioactivity released into the atmosphere was approximately one-tenth as much as was released during the Chernobyl disaster. Significant amounts of radioactive material have also been released into ground and ocean waters. Measurements taken by the Japanese government 30–50 km from the plant showed radioactive caesium levels high enough to cause concern,  leading the government to ban the sale of food grown in the area. Tokyo officials temporarily recommended that tap water should not be used to prepare food for infants.
A few of the plant's workers were severely injured or killed by the disaster conditions resulting from the earthquake. There were no immediate deaths due to direct radiation exposures, but at least six workers have exceeded lifetime legal limits for radiation and more than 300 have received significant radiation doses. Future cancer deaths due to accumulated radiation exposures in the population living near Fukushima have ranged from none  to 100  to a non-peer-reviewed "guesstimate" of 1,000.  Fear of ionizing radiation could have long-term psychological effects on a large portion of the population in the contaminated areas. On 16 December 2011 Japanese authorities declared the plant to be stable, although it would take decades to decontaminate the surrounding areas and to decommission the plant altogether.

植物はもともとゼネラル·エレクトリック(GE)によって設計された6つの独立した沸騰水型原子炉を含み、東京電力株式会社(TEPCO)によって管理されています。 5と6は、計画的なメンテナンスのために冷態停止にあった間に地震の時に、原子炉4はド支えていました。
 残りの原子炉は地震後に自動的にシャットダウンされ、非常用発電機は、エレクトロニクスと冷却システムを制御するためにオンラインになった。津波は、電力グリッドに原子炉 '接続を破って、また非常用発電機を含む部屋の氾濫をもたらした。したがって、これらのジェネレータは、作業を終え、原子炉に冷却水を循環させるポンプは、原子炉が過熱し始めることを引き起こして、作業を中止した。洪水や地震被害は、外部の援助を妨げた。
工場の労働者の数は、重傷を負ったり、地震に起因する災害の状況によって殺された。そこに直接の放射線被ばくに起因する即時の死亡はなかったが、少なくとも6つの労働者は、放射線の有効期間の法的制限を超えており、300人以上が重要な放射線量を受けています。福島の近くに住む住民の累積放射線被ばくに起因する将来のがんによる死亡は1,000の非査読 "推量"になしから100の範囲であった。電離放射線の恐怖は、汚染地域の人口の大部分の長期心理的な影響を及ぼす可能性があります。上の2011年12月16日、日本の当局は、それが周辺地域を除染するために何十年もかかると完全に廃止工場になるものの、安定しているように植物を宣言した。

April 20, 2012

Mounting troubles at Japan’s hobbled Fukushima Dai-Ichi nuclear power plant now pose a real threat to human survival. If the area in which Unit 4 is struck by another 7.0 magnitude earthquake, there’s a 70 percent chance that “the entire fuel pool structure will collapse” and massive doses of lethal nuclear radiation will be released into the atmosphere. The disaster would release approximately “134 million curies is Cesium-137 — roughly 85 times the amount of Cs-137 released at Chernobyl as estimated by the U.S. National Council on Radiation Protection (NCRP).” Experts believe that the amounts are sufficient to “destroy the world environment and our civilization”, which makes containment “an issue of human survival.” (“The Greatest Single Threat to Humanity: Fuel Pool Number 4″


日本の足を引きずり福島第一原子力発電所での取り付けのトラブルは今人類の生存に対する真の脅威となっている。ユニット4の領域は別の7.0の地震に襲われている場合は、"全体の燃料プールの構造は崩壊する"と致命的な核放射線の大量投与が大気中に放出されることが70パーセントの確率ではありません。災害は "セシウム137です1.34億キュリーを - として放射線防護に関する米国評議会(NCRP)により推定チェルノブイリで放出Cs-137の約85倍の量"を約放出する専門家は金額が"に十分であると信じている。燃料プール番号4 ":世界の環境と人間の生存の問題"​​封じ込めを行い、"我々の文明を"( "人類の最大の単一の脅威を破壊

Update from greenpeace.

State of the Reactors

TEPCO announced that nitrogen gas injection into reactors #1, #2, and #3 stopped unexpectedly for nearly nine hours this week. Workers are continuing to inject nitrogen into the crippled reactors in order to prevent more hydrogen explosions; failure to do so could be exceedingly dangerous. However, TEPCO officials said that hydrogen levels remained stable, and there was no increased risk of explosion. This is the fourth time that nitrogen injections have failed in the last six weeks.
A second thermometer has broken in Fukushima Daiichi’s reactor #2, leaving only one working temperature sensor. According to officials it will take up to 10 years to remove molten fuel from the reactor vessel, and temperature monitoring is crucial to ensuring that another meltdown doesn’t occur. Normally, thermometers and other equipment are tested and often replaced every 13 months. However, extremely high radiation levels are preventing workers from getting close enough to the reactor to perform repairs. Experts are concerned that the one remaining temperature gauge will not last 10 years, and are worried about overall stability of the reactors, as well as TEPCO’s ability to monitor their safety.
TEPCO discovered that a 35-ton crane fell into the spent fuel pool at reactor #3 of the Fukushima Daiichi plant, along with significant amounts of debris, and is resting atop fuel storage racks beneath the water. Utility officials, who were using a camera to explore the interior of the pool, believe that the fall occurred during hydrogen explosions last March. The crane, in addition to other debris, will need to be removed from the pool before fuel is removed and the reactor can be decommissioned. Experts expect the process to be challenging.


Officials from Miyagi Prefecture have discovered high levels of radioactive cesium in Yakon tea, a beverage made from root vegetables that is consumed for its healthful effects. Samples measured 17,200 Bq/kg, 172 times the legal limit for cesium. Over 1,000 packages were sold online and in stores, under the brand name GOLDbrand. The company has issued a voluntary recall, and prefectural officials are testing other brands of the tea.





宮城県から職員がYakon茶は、その健康的な効果のために消費されているルートの野菜から作られた飲料では放射性セシウムの高レベルのを発見しました。サンプルは17200 Bq / kgで、セシウムのために172倍の法的限界を測定した。 1,000を超えるパッケージがブランド名GOLDbrandの下で、オンラインと店舗を売却された。同社は自主回収を発行しており、県の職員は、お茶の他のブランドをテストしています。


Tsuruga Nuke Plant Reactor 2 May Have Been Sitting on Top of Active Fault All These Years

As the mayor of Tsuruga City was strongly promoting nuclear power generation in the county in China that has a nuclear power plant with 6 operating reactors and 4 under construction, the Nuclear and Industrial Safety Agency warned the operator of Tsuruga Nuclear Power Plant that Reactor 2 of the plant may be sitting on an active fault.

Even in Japan, the national guideline is not expecting a reactor to be built on top of an active fault.

Reactor 2 of Tsuruga Nuclear Power Plant is a pressurized water reactor made by Mitsubishi Heavy Industries. Reactor 1 is a light water reactor by GE. Tsuruga's Reactor 2 was considered to be one of the better made PWRs in Japan. Both reactors have been shut down for regular maintenance.

Construction of Reactor 2 started in 1982, and the reactor started operation in 1987.

Two more reactors are being built at Tsuruga Nuke Plant. The reactors will be Advanced Pressurized Water Reactors (APWR) by Mitsubishi Heavy Industries. If they proceed with the construction, that is.

From NHK News (4/25/2012):

"An active fault" at Tsuruga Nuclear Power Plant to be studied again


An expert has pointed out the possibility that cracks that run under Tsuruga Nuclear Power Plant in Fukui Prefecture are active faults. The Japan Atomic Power Company (JAPC) is going to do the survey again and come up with the plan.


On April 24, an expert in active faults and officials from the Nuclear and Industrial Safety Agency (NISA) studied the area where the strata are exposed at JAPC's Tsuruga Nuclear Power Plant in Tsuruga City in Fukui Prefecture. They particularly looked at the crack called "fracture zone".


As the result, the expert pointed out that the crack that runs underground at about 150 meters west of Reactor 2 "may be an active fault, and it may move together with the active fault called Urazoko Fault that runs through the compound, making the shaking from an earthquake bigger than anticipated".


There is another crack that runs right beneath Reactor 2. It needs to be studied to determine if it is also an active fault. NISA has instructed JAPC to do the survey again.


The guideline for seismic design by the national government does not expect having an important facility of a nuclear power plant right above an active fault. If the crack beneath Reactor 2 turns out to be an active fault, there is a possibility that JAPC cannot restart the reactor.


JAPC will report to NISA shortly with the plan for the survey, and will study the strata to decide what to do.


JAPC says, "The result of the survey may affect various issues such as expected maximum earthquake and seismic stability of the plant. We would like to proceed very cautiously."

Thank you for this most important information.


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