原文链接:
http://www.bbc.co.uk/news/science-environment-23779561
By Matt McGrath Environment correspondent, BBC News
Mycle Schneider is an independent consultant who has previously advised the
French and German governments.
He says water is leaking out all over the site and there are no accurate
figures for radiation levels.
Meanwhile the chairman of Japan's nuclear authority said that he feared there
would be further leaks.
The ongoing problems at the Fukushima plant increased in recent days when the
Tokyo Electric Power Company (Tepco) admitted that around 300 tonnes of highly
radioactive water had leaked from a storage tank on the site.
Moment of crisis
The Japanese nuclear energy watchdog raised the incident level from one to
three on the international scale that measures the severity of atomic accidents.
Continue reading the main story
“Start Quote
It is leaking out from the basements, it is leaking out
from the cracks all over the place”
End
Quote Mycle Schneider Nuclear consultant This was an acknowledgement that the power station was
in its greatest crisis since the reactors melted down after the tsunami in
2011.
But some nuclear experts are concerned that the problem is a good deal worse
than either Tepco or the Japanese government are willing to admit.
They are worried about the enormous quantities of water, used to cool the
reactor cores, which are now being stored on site.
Some 1,000 tanks have been built to hold the water. But these are believed to
be at around 85% of their capacity and every day an extra 400 tonnes of water
are being added.
"The quantities of water they are dealing with are absolutely gigantic," said
Mycle Schneider, who has consulted widely for a variety of organisations and
countries on nuclear issues.
"What is the worse is the water leakage everywhere else - not just from the
tanks. It is leaking out from the basements, it is leaking out from the cracks
all over the place. Nobody can measure that.
Satellite images show how the
number of water storage tanks has increased in the past two years. The tanks
store contaminated water that has been used to cool the reactors.
"It is much worse than we have been led to believe, much worse," said Mr
Schneider, who is lead author for the World Nuclear Industry status reports.
At news conference, the head of Japan's nuclear regulation authority Shunichi
Tanaka appeared to give credence to Mr Schneider's concerns, saying that he
feared there would be further leaks.
``We should assume that what has happened once could happen again, and
prepare for more. We are in a situation where there is no time to waste," he
told reporters.
The lack of clarity about the water situation and the continued attempts by
Tepco to deny that water was leaking into the sea has irritated many
researchers.
Dr Ken Buesseler is a senior scientist at Woods Hole Oceanographic
Institution who has examined the waters around Fukushima.
"It is not over yet by a long shot, Chernobyl was in many ways a one week
fire-explosive event, nothing with the potential of this right on the
ocean."
"We've been saying since 2011 that the reactor site is still leaking whether
that's the buildings and the ground water or these new tank releases. There's no
way to really contain all of this radioactive water on site."
"Once it gets into the ground water, like a river flowing to the sea, you
can't really stop a ground water flow. You can pump out water, but how many
tanks can you keep putting on site?"
Several scientists also raised concerns about the vulnerability of the huge
amount of stored water on site to another earthquake.
Water from the storage tanks
has seeped into the groundwater and then into the sea. Efforts to use a chemical
barrier to prevent sea contamination have not worked
New health concerns The storage problems are compounded by the ingress of ground water, running
down from the surrounding hills. It mixes with radioactive water leaking out of
the basements of the reactors and then some of it leaches into the sea, despite
the best efforts of Tepco to stem the flow.
Some of the radioactive elements like caesium that are contained in the water
can be filtered by the earth. Others are managing to get through and this
worries watching experts.
"Our biggest concern right now is if some of the other isotopes such as
strontium 90 which tend to be more mobile, get through these sediments in the
ground water," said Dr Buesseler.
"They are entering the oceans at levels that then will accumulate in seafood
and will cause new health concerns."
There are also worries about the spent nuclear fuel rods that are being
cooled and stored in water pools on site. Mycle Schneider says these contain far
more radioactive caesium than was emitted during the explosion at Chernobyl.
"There is absolutely no guarantee that there isn't a crack in the walls of
the spent fuel pools. If salt water gets in, the steel bars would be corroded.
It would basically explode the walls, and you cannot see that; you can't get
close enough to the pools," he said.
The "worsening situation" at Fukushima has prompted a former Japanese
ambassador to Switzerland to call for the withdrawal of Tokyo's Olympic bid.
In a letter to the UN secretary general, Mitsuhei Murata says the official
radiation figures published by Tepco cannot be trusted. He says he is extremely
worried about the lack of a sense of crisis in Japan and abroad.
This view is shared by Mycle Schneider, who is calling for an international
taskforce for Fukushima.
"The Japanese have a problem asking for help. It is a big mistake; they badly
need it."
福岛核污水泄漏升至严重等级
原文链接: http://news.xinhuanet.com/world/2013-08/30/c_125278787.htm
2013年08月30日 07:43:43 来源:人民网
日本福岛第一核电站近期曝出储水罐放射性污水大量泄漏事件,日本原子能规制委员会28日决定将该事件评定为3级(严重)。福岛县知事佐藤雄平称之为“国家非常事态”,要求日本政府早日拿出对策。
对此,日本首相安倍晋三28日在卡塔尔表示,政府将担起责任全力应对。
此前,中国国家海洋局于25日发布消息称,日本福岛核事故后产生的放射性污染物,目前对我国管辖海域暂无影响。
事故级别提高到3级
成“国家非常事态”
本月7日,日本政府宣布,福岛核电站每天至少有300吨遭受核污染的地下水流入大海,且这种情况可能从福岛核事故之后一直存在。19日,东京电力公司承认放射性污水储水罐漏水,日本原子能规制委员会当时将事故暂定为1级(异常)。东京电力公司21日又报告称,发现共约300吨高浓度放射性污水从地面蓄水罐泄漏,原子能规制委员会随即表示可能将事故级别提高到3级。28日,原子能规制委员会在例会上正式作出这一决定,并通报国际原子能机构。
福岛县知事佐藤雄平28日对日本经济产业大臣茂木敏充说,福岛第一核电站污水泄漏不断,这种状态是“国家非常事态”,要求日本政府全力应对。
2011年的福岛第一核电站事故本身是最严重的7级(特大),3级属从上至下的第5个等级。国际原子能机构在与日方的沟通中认为,福岛第一核电站的核污水储水罐虽然属于应急设施,同样适用于国际核事故分级。
东电难以免责
储水罐泄漏近1/3才发现
据报道,虽然东京电力公司本月19日承认放射性污水储水罐漏水,但并非第一时间发现问题,一个核污水储水罐几乎泄漏了三分之一才被发现。东电本来可以及早避免事态。东电27日承认,早在7月9日,在泄漏处附近检查工作的职员就在日常辐射检查中被检出辐射值上升,但没有认真调查原因,因此东电在这次事故中难以免责。
福岛核事故发生以来,为持续冷却核燃料,福岛核电站已累计产生了至少33.5万吨核污水。东电搭建起上千个钢制储水罐储存这些核污水,而这些匆忙拼凑的廉价钢制储水罐可能存在一些问题,比如用于冷却反应堆的海水容易腐蚀罐体,储水罐没有水位计,罐体设计可能存在缺陷,其他罐体也可能出现漏水问题等。
日本原子能规制委员会委员长田中俊一在28日的记者会上对东电提出了严厉批评,他说东电的调查混乱不严谨,泄漏300吨污水的推测没有证据。因为罐体没有水位计,发觉泄漏时污水比满罐时少了300吨,原本是否满罐也不清楚。而且,这些污水流到哪去了也不清楚。
部分核污水可能入海
专家称不会造成威胁
此次泄露的污水达300吨,但东电迄今只收集到4吨泄漏污水,称大部分泄漏污水可能已经渗入储水罐区周边土壤。然而,这家电力运营商日前公布的数据显示,污水可能已经流入附近海中。
东电方面21日在储水罐区附近一条排水沟内探测到每小时6毫希沃特的辐射水平,这意味着一些泄漏污水可能已经流入,而这条排水沟连接通向大海的另一条排水沟。
东电副社长相泽善吾说,这家企业正具体研究污水入海的可能性。原子能规制委员会则敦促核电站作业人员从海水中采集样本分析。
英国曼彻斯特大学多尔顿核研究所主任安德鲁・谢里说,污水泄漏尽管严重,比两年前还是轻得多。一些核电专家同样认为,泄漏不会给日本和邻国造成威胁。
不过,韩国亚洲航空公司宣布,考虑到公众对辐射污水泄漏的担忧,这家航空运营商将取消今年10月往返韩国首都首尔和福岛县首府福岛市的包机航班。福岛市距离福岛第一核电站大约60公里,是高尔夫球爱好者和温泉游游客的热门旅游目的地。
渔业团体抗议
日本政府口号大于行动
此次泄漏事件也让当地的渔业团体愤怒,全国渔业协会联合会和福岛等地渔业协会专门到东电提出抗议,认为此次事件是对全国渔民和国民的背叛行为,要求东电彻底改进污水处理对策,加强海域监测。
此外,福岛县渔业协会联合会28日在磐城市召开会议,正式决定9月以后中止在福岛县海域开展试验性捕捞。
相关渔业团体还向政府提交了请愿书,要求政府为防止核污水流入海洋采取根本性解决措施,向国内外提供有关日本水产品安全性的准确信息。
此前,安倍在广岛市和平纪念仪式上致辞时说:“我们确实有责任和义务去实现无核世界。”而从福岛核事故发生至今已经过去两年半,东电从头至尾都在隐瞒问题的严重性。日本政府也遮遮掩掩,在处理核泄漏的过程中行动迟缓,没有及时向外界公布有关情况。虽然日本首相安倍晋三28日称,日本政府将担起责任应对事态,但是目前看来依然是口号大于行动。