東電表示，外洩的高輻射污水其β輻射數據為每公升二．三億貝克。其中近半數的β輻射來自鍶-90，這意味污水的鍶-90濃度是法定標準每公升卅貝克的近四百萬倍。
會在骨骼中累積 有罹癌之虞
β輻射會對人體造成嚴重傷害，並將損及ＤＮＡ，所幸它容易避免，同時無法穿透薄薄的鋁片。而鍶-90一旦吸收，會在骨骼中累積，並有罹癌之虞。
東電說，這起外洩事故導因於閥門未關，致使過多的污水流進儲存槽中，一名工作人員於十九日深夜十一點半巡邏該區，發現儲存槽邊的排水設施有水溢出，經六小時的緊急處理，於翌日清晨五點四十分止住漏水。
東電表示，目前正進行外洩水與污染土壤的回收工作，由於儲存槽距海岸有七百公尺，加上周邊沒有地下排水管，因此不太可能流入海。
聯合國核安3級嚴重事故
福島核電廠數百座的儲存槽，是用來存放三年前三一一強震後，冷卻受損反應爐過程中遭污染的輻射水。去年八月，約三百公噸的輻射水外洩，日本當局指出，該事故在聯合國七級的國際核子事件分級中，為三級的「嚴重事故」；十九日晚間的溢流也被認為相同等級。
福島縣當局廿日指出，官方與警方彙整的數據顯示，三一一強震海嘯災後三年，福島死於該災難有關的壓力或其他疾病者達一千六百五十六人，已超過在重災中喪生的一千六百零七人。
災後三年，福島許多人仍流離失所。官員說，災後初期，一些人因欠缺妥善的醫療照護而送命，然而越來越多人因留在避難所的身心壓力而死亡，其中包括自殺。2014.2.20
A tank at Japan’s damaged Fukushima nuclear plant has leaked another 100 metric tons of highly contaminated water, the worst incident since August: http://ti.me/1nPB4EB
福島核電站再次發現污水泄漏
2013年06月06日
東京——福島核電站的運營者於本周三表示，公司發現，在這個受損嚴重的核電站里，用來存儲站內放射性污水的數百個鋼質水槽當中已有一個發生了泄漏。泄漏事故再度引發了人們對該公司清污能力的質疑。
此次泄漏被發現的前一日，前述運營者東京電力公司
（Tokyo Electric Power Company，簡稱東電）的一名操作人員承認，公司已在流入福島第一核電站(Fukushima
Daiichi)的地下水中發現了銫微粒，這一說法推翻了東電早些時候斷言地下水未被污染的聲明。
東電強調，水槽泄漏事故的規模相當小，到目前為止，只有大
約1夸脫（約0.95升）的污水流出。公司還說，地下水的放射水平依然處於安全範圍之內。然而，這些問題是一連串的錯誤和災難中最新的一批，它們加劇了人
們對政府逐漸增加的指責，因為政府決定把棘手的清污任務交到東電手中。許多人說，該公司是導致核電站兩年前發生三重熔融事故的根本原因。
最近，東電一直在竭力處理核電站內數千萬加侖的有毒污水，
這些污水必須被存儲在大型鋼槽內，現在，鋼槽實際上已佔據了核電站里每一寸可用的空間。隨着地下水以每日10萬加侖的速度流入受損核反應堆廠房的地下室，
放射性污水的水量還在持續增加。這些污水每天都得進行轉移，以防止它們淹沒冷卻熔毀反應堆的臨時系統。
東電安裝了一個新的過濾系統，說它能去除除了氚之外的所有放射性微粒。然而，這樣的過濾效果還是讓東電別無選擇，只能繼續存儲污水，不能把它們倒掉。
周三的泄漏突顯了在電站存儲污水的風險，在這裡，規模更大的泄漏可能會直抵不遠處的太平洋。發生泄漏的水槽是剛剛安裝來儲存有毒廢水的。這些廢水原本被存放在一個地下儲水池裡，那個水池也發生了泄漏，不得不清空，廢水才被轉移到了這個水槽里。
面對民眾對水危機越來越高的警惕，政府上周命令東電凍結反應堆建築附近的泥土，以阻止地下水流入。這是一個新奇的計劃，需要公司築起一堵地下冰牆。東京電力公司還計劃在部分地下水抵達反應堆建築並受到污染之前將其泵到海里，以此減少地下水的流入。
然而，泵水計劃需要得到緊鄰電站周邊疏散區的居民和商業漁民的同意。自堆芯熔化使輻射泄漏至整個日本東北部之後，這些人一直在慢慢地恢復生計。東京電力公司一直在向他們保證，要排出的水裡不含會進一步污染海洋的放射性粒子。
公司員工周二承認地下水裡確實含有堆芯熔化的副產品銫，這可能會讓前述計劃陷入困境。東京電力公司承認之前的檢測存在失誤，並稱在每升水中發現了0.39貝克的放射性銫-137，這一數字遠低於日本每升10貝克的飲用水安全標準。
儘管如此，這仍有可能破壞東京電力公司把地下水泵到海里的
計劃，至少也可能會讓這個計劃暫停。就在上周，該公司還告訴當地的漁業合作社，地下水的銫含量非常低，根本檢測不出來，試圖以此說服它們。早在東電員工周
二承認事實之前，漁民就對這些保證提出了強烈質疑，表示自己不再相信東電的任何斷言。
Leak Found in Steel Tank for Water at Fukushima
June 06, 2013
TOKYO — The operator of the stricken Fukushima
nuclear plant said Wednesday that it had found a leak in one of the
hundreds of steel tanks used to store radioactive water at the plant,
raising renewed questions about the company’s ability to handle the
plant’s cleanup.
The discovery comes a day
after the operator, the Tokyo Electric Power Company, or Tepco, admitted
that it had found cesium particles in groundwater flowing into the
Fukushima Daiichi plant, reversing its earlier assertion that the water
was uncontaminated.
The company stressed that
the size of the tank leak was small — the equivalent of about a quart
had dripped out so far, it said — and that the level of radioactivity in
groundwater was within safe levels. However, the problems are the
latest in a string of mistakes and mishaps that have added to mounting
criticism of the government’s decision to leave the tricky cleanup in
the hands of Tepco, the company that many say allowed the triple
meltdown two years ago to happen in the first place.
Recently, Tepco has
struggled to deal with tens of millions of gallons of contaminated,
toxic water at the plant, which must be stored in the large steel tanks
that now occupy virtually every available bit of space there. The amount
of radioactive water has continued to grow as groundwater has flowed at
a rate of 100,000 gallons per day into the basements of the damaged
reactor buildings. This contaminated water must be drawn off every day
to prevent it from overwhelming makeshift systems that cool the melted
reactors.
The company has installed a
new filtering system that it says removes every type of radioactive
particle but one, tritium. Still, that leaves it no choice but to keep
storing the water rather than dumping it.
Wednesday’s leak
underscored the risks of doing so at the plant, where a larger spill
might potentially reach the nearby Pacific Ocean. The leaking tank had
just been installed to store toxic water from an underground storage
pond that needed to be emptied after it, too, sprang a leak.
Faced with growing public
alarm over the water crisis, the government last week ordered Tepco to
stop the influx of groundwater by freezing soil around the reactor
buildings, a novel plan that calls for creating a wall of underground
ice. The company has also planned to reduce the influx by pumping some
of the groundwater into the sea before it reaches the buildings and
becomes contaminated.
However, the pumping plan
needs the approval of residents and commercial fishermen in areas
outside the evacuation zone immediately around the plant, who have been
slowly regaining their livelihoods since the meltdowns spewed radiation
over northeastern Japan. The company had been offering them reassurances
that the water to be dumped contained no radioactive particles that
could further contaminate the ocean.
Those plans could now be
jeopardized by Tuesday’s admission that the groundwater in fact does
contain cesium, a byproduct of the meltdowns. The company, which
conceded that it had erred in previous tests, said it had found up to
0.39 becquerels of radioactive cesium 137 per liter of water, an amount
that is far below Japan’s safety level for drinking water of 10
becquerels per liter.
Still, it may be enough to
scuttle or at least put on hold the company’s plan to pump groundwater
into the sea. Just last week, the company sought to persuade local
fishing cooperatives by telling them that levels of cesium in the
groundwater were so low that they could not be detected. Those
reassurances were met with intense skepticism by fishermen who, even
before Tuesday’s admissions, said they no longer trusted any assertions
made by Tepco.
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