2011年3月31日 星期四

福島核電站災難應急方案嚴重不足 Japanese Plant Had Barebones Risk Plan

Japanese Plant Had Barebones Risk Plan
Tokyo Electric Power Co.'s disaster plans greatly underestimated the scope of a potential accident at its Fukushima Daiichi nuclear plant, calling for only one stretcher, one satellite phone and 50 protective suits in case of emergencies.

Disaster-response documents for Fukushima Daiichi, examined by The Wall Street Journal, also contain few guidelines for obtaining outside help, providing insight into why Japan struggled to cope with a nuclear crisis afteran earthquake and tsunami devastated the facility.

The disaster plans, approved by Japanese regulators, offer guidelines for responding to smaller emergencies and outline in detail how to back up key systems in case of failure. Yet the plans fail to envision the kind of worst-case scenario that befell Japan: damage so extensive that the plant couldn't respond on its own or call for help from nearby plants. There are no references to Tokyo firefighters, Japanese military forces or U.S. equipment, all of which the plant operators eventually relied upon to battle their overheating reactors.

On Wednesday, the president of plant operator Tepco was hospitalized for dizziness, offering the latest sign of leadership trouble. Earlier in the disaster, Tepco was faulted for a sluggish initial response; now it appears that its written emergency plans were themselves inadequate.

'The disaster plan didn't function,' said a former Tepco executive. 'It didn't envision something this big.'

The two main documents examined by the Journal are Fukushima Daiichi's disaster-readiness plan, which discusses general preparations and communications, and its accident-management protocol, which focuses on technical operation of plant equipment in an accident.

The main disaster-readiness manual, updated annually, envisions the fax machine as a principal means of communication with the outside world and includes detailed forms for Tepco managers when faxing government officials. One form offers a multiple-choice list of disasters, including 'loss of AC power,' 'inability to use the control room' and 'probable nuclear chain reaction outside the reactor.'

Tepco spokesman Hiro Hasegawa said the plans followed and sometimes exceeded legal requirements, and proved useful in the crisis. For example, he said the emergency injection of water to cool the reactors followed the accident-management protocol.

Nuclear-power experts say few operators anywhere are likely prepared for the kind of disaster that struck Fukushima Daiichi. On March 11, the plant was hit with a magnitude 9.0 quake, followed by a tsunami estimated at 45 feet. The twin catastrophes wiped out the normal power and backup generators of nearly all the plant's six reactors and also damaged roads and communication lines through which the plant could seek help.

Previous big nuclear accidents, such as those at Three Mile Island in the U.S. and Chernobyl in the former Soviet Union, resulted from poor safety standards and bad management, said Kazuo Sato, a consultant at the Nuclear Safety Research Association, who headed Japan's watchdog Nuclear Safety Commission in the late 1990s. 'This one was a natural disaster -- it's qualitatively different,' he said.

The International Atomic Energy Agency, a United Nations agency, has hundreds of pages of safety recommendations for nuclear-facility operators, but its recommendations aren't binding on individual countries. An IAEA spokesman declined to comment on whether Japanese emergency plans fulfill IAEA guidelines.

The Journal compared the Fukushima Daiichi accident-management protocol against the IAEA's general principles, and it appears the plant document generally hews to them. However, the IAEA calls for operators to cover 'appropriately selected external events, such as fires, floods, seismic events and extreme weather conditions. . .that could damage large parts of the plant.' The Fukushima Daiichi protocol doesn't specifically discuss how such events could damage the plant.

In the U.S., operators are expected to continuously update emergency plans and to conduct large-scale drills, typically lasting from eight hours to two days, at least every two years. The exercises are graded by the U.S. Nuclear Regulatory Commission, which requires correction of deficiencies. The NRC describes the capabilities it expects plants to have but often doesn't specify the equipment required.

Critics allege Japan's regulators and operators tend to avoid talking about or preparing fuller disaster scenarios, partly to avoid scaring the public. Fukushima Daiichi's own report on its accident-management protocols says: 'The possibility of a severe accident occurring is so small that from an engineering standpoint, it is practically unthinkable.'

Banri Kaieda, chief of the Ministry of Economy, Trade and Industry, said Wednesday that the ministry's Nuclear and Industrial Safety Agency plans to tighten scrutiny of emergency plans in light of Fukushima Daiichi. 'We are painfully aware' the plans were inadequate, an agency spokesman said.

Following Three Mile Island and Chernobyl, Japan's industry ministry in 1992 asked nuclear operators to come up with voluntary protocols for each of their plants in the case of accidents that exceeded their safety specifications. Those 'accident-management plans' don't have to be periodically revised. Tepco submitted the report on its plan for Fukushima Daiichi in 2002.

A serious accident at a Japanese uranium-processing facility in 1999 led Parliament to pass a law on nuclear emergencies. The law requires operators to have 'disaster-readiness operation plans,' reviewed annually. It also sets base protocols that operators must follow, such as minimum numbers of masks.

In some cases, Fukushima Daiichi's crisis planners exceeded minimums. The plan calls for 49 radiation-detecting meters, versus six required by law, and 100 cellphones on two systems, versus the seven required.

Still, many of the numbers suggest the six-reactor plant anticipated at most a modest emergency. It calls for a four-man medical team to attend to people exposed to radiation and other victims. Four protective suits with oxygen tanks were to be stocked, as well as a single ambulance and radiation-measuring vehicle.

Much hinged on the fax machine. One section directs managers to notify the industry minister, the local governor and mayors of nearby towns of any problems 'all at once, within 15 minutes, by facsimile.' In certain cases, the managers were advised to follow up by phone to make sure the fax had arrived.

The disaster-response plans at other operators in Japan follow the same structure as Fukushima Daiichi's, although some are more thorough.

Accident-management plans are generally written to deal with internal plant problems and don't take into account external shocks such as a quake or terrorist attack, said Hokkaido University Prof. Kenichiro Sugiyama, who served on a government panel on nuclear accident readiness.

Tepco's Mr. Hasegawa said the company is doing its utmost to put in place 'emergency-response measures based on the operational plan for disaster prevention.' He pointed to successful steps such as the establishment of a disaster headquarters as soon as the quake struck.

After this crisis is settled, Japan will have to rethink everything, industry veterans said. This catastrophe shows 'there is no such thing as overdoing it' in preparing a disaster manual, said Tsuneo Futami, who was superintendant at Fukushima Daiichi from 1997 to 2000. The attitude must be that 'anything can happen tomorrow.'


2011年 03月 31日 15:00
福島核電站災難應急方案嚴重不足


京電力公司(Tokyo Electric Power Co.)的災難應急方案大大低估了福島第一核電站可能事故的規模﹐僅僅配備了一副擔架、一部衛星電話和50套防護服應急。

European Pressphoto Agency
3月早些時候的東京電力公司福島第一核電站。
《華爾街日報》看了福島第一核電站的災難響應文件﹐其中對獲取外部幫助的指導很少﹐這也解釋了福島第一核電站在遭受地震和海嘯的破壞後﹐日本為什麼難以應對一場核危機。

災 難應急方案獲得了日本監管機構的批准﹐提供了應對小規模緊急事故的指導﹐並詳細介紹了如何為關鍵系統提供備用系統﹐以防出現故障。然而﹐方案沒有預見到日 本眼下面臨的最糟糕的情況﹕受損規模非常大﹐以致於核電站無法獨立應對﹐也無法從附近核電站尋求幫助。方案沒有提供聯繫東京消防員、日本部隊或美國設備的 方法。這次﹐核電站運營商最終是依靠這些來努力控制過熱反應堆的。

週三﹐福島第一核電站運營商東京電力公司總裁因頭暈入院治療﹐再次顯示了領導層的問題。在災難發生的初期﹐東京電力公司因最初反應遲緩而受到指責﹐如今看來書面應急方案本身就不夠充分。

一名前東京電力公司高管說﹐災難應急方案沒有起作用﹐它沒有預見到如此大規模的災難。

《華爾街日報》看到的兩份主要文件是福島第一核電站的災難準備方案和事故管理程序。災難準備方案討論了一般性的準備工作和通訊。事故管理程序則著重於發生事故時核電站設備的技術操作。

主要的災難準備手冊每年都會更新﹐它把傳真機作為與外界通訊的主要工具﹐包括東京電力公司管理人員向政府官員發傳真的具體表格。一份表格列出了各種災難﹐包括“交流電源喪失”﹐“控制室無法使用”﹐“反應堆外可能的核連鎖反應”。

東京電力公司發言人谷川和弘(Hiro Hasegawa)說﹐應急方案符合法律要求﹐有時甚至超過了法律要求﹐事實證明﹐方案在此次危機中起作用了。他說﹐舉例來講﹐緊急注水冷卻反應堆就是按照事故管理程序規定做的。

核 電專家說﹐全球很少有運營商準備會應對福島第一核電站遭受的這樣的災難。3月11日﹐該核電站遭受了里氏9.0級的地震﹐之後又發生了浪高約45英尺(約 合14米)的海嘯。地震和海嘯的雙重打擊破壞了常用供電系統﹐全部六個反應堆的備用發電機幾乎都無法工作﹐還摧毀了道路和通訊線路﹐使核電站無法向外界求 助。

核 安全研究協會(Nuclear Safety Research Association)顧問佐藤一男(Kazuo Sato)說﹐此前的嚴重核事故﹐比如美國三里島(Three Mile Island)和前蘇聯切爾諾貝利(Chernobyl)核事故﹐都是因為安全標準鬆懈和管理不善造成的﹐而這次是一場自然災害﹐性質是不同的。上世紀 90年代末﹐他曾主管日本原子力安全委員會(Nuclear Safety Commission)。

聯合國國際原子能機構(International Atomic Energy Agency)對核電站運營商有著數百頁的安全建議﹐不過這些建議並不是各個國家都必須遵守的。國際原子能機構發言人拒絕就日本應急方案是否滿足國際原子能機構的準則置評。

《華 爾街日報》將福島第一核電站的事故管理程序與國際原子能機構的一般原則進行了比較﹐看來該核電站的文件總體符合一般原則。不過﹐國際原子能機構呼籲運營商 要考慮到“適當選擇的外部事件﹐比如火災、水災、地震和極端天氣情況﹐這些可能造成核電站大部分受損的事件”。 福島第一核電站的程序沒有具體討論這類事件如何會令核電站受損。

在美國﹐運營商會反復更新應急方案並進行大規模演習﹐一般每次持續八小時 到兩天不等﹐每兩年至少演習一次。美國核管理委員會(U.S. Nuclear Regulatory Commission)對演習進行評估﹐需要糾正方案的不足之處。NRC會敘述它希望核電站擁有的能力﹐但通常不會具體說明所需的設備。

批評人士聲稱﹐日本的監管機構和運營商往往會避免談及或預備好更全面的災難情況﹐部分是為避免令公眾恐懼。福島第一核電站在其所做的事故管理規程報告中說﹐發生嚴重事故的可能性是極小﹐從工程學角度來看﹐這幾乎是難以想象的。

日 本經濟產業省大臣海江田萬里(Banri Kaieda)週三說﹐鑒於福島第一核電站的情況﹐該部門的原子力安全保安院(Nuclear and Industrial Safety Agency)計劃加緊對應急方案的監管。保安院一位發言人說﹐我們艱難地認識到﹐這些方案是不充分的。

三里島和切爾諾貝利核事故後﹐日本產業省在1992年要求核電站運營商針對核電站事故超過安全規格的情況自行提交每個核電站的管理章程。這些“事故管理方案”不需要定期修改。東電在2002年提交了自己對福島第一核電站的方案。

1999年﹐日本一座鈾處理工廠發生嚴重事故﹐議會因此通過了一項核事故應急法案。該法案要求運營商有“應對災難的操作方案”﹐每年審查一次。同時還制定了運營商必須遵守的章程﹐例如防護罩的最少數目。

某些情況下﹐福島第一核電站的應急方案規劃者們超出了最低要求。該方案要求配備49個輻射探測儀並在兩個系統安裝100部手機﹐法律規定的分別是六個和七部。

然而﹐許多數字表明﹐這座擁有六座反應堆的核電站最多只是預見到了一場不太大的危機。電站要求一個四人醫療隊照顧被輻射的人員和其他災民﹐儲備四套帶有氧氣袋的防護服、僅一輛救護車和輻射測量車。

大部分工作取決於那台傳真機。方案中的一部分指導說﹐若發生任何問題﹐經理要在15分鐘內用傳真一併通知產業大臣、地方知事和附近城鎮的市長。某些情況下﹐經理們被要求再致電確認傳真是否正常發到。

日本其他運營商的災難響應方案與福島第一核電站的結構一樣﹐但有些更完備。

北海道大學(Hokkaido University)教授Kenichiro Sugiyama說﹐制定事故管理方案通常用於處理核電站內部問題﹐未考慮地震或恐怖襲擊這樣的外部沖擊。他是一個政府核事故應急小組的成員。

東電發言人谷川和弘說﹐公司正在盡最大努力根據預防災難操作方案使應急措施到位。他提到了諸如在地震發生時就建立災難應急指揮部的成功措施。

資深行業人士說﹐此次危機平息後﹐日本必須要對一切重新進行考慮。福島第一核電站1997年至2000年間的管理人Tsuneo Futami說。此次大災難表明﹐在準備災難手冊時“沒有做過頭這一說”。態度應該是“明天什麼事都可能發生”。

Phred Dvorak / Peter Landers

沒有留言: