8 Mai 2013
May 8, 2013
http://mainichi.jp/english/english/newsselect/news/20130508p2g00m0dm044000c.html
TOKYO (Kyodo) -- The operator of the crippled Fukushima Daiichi nuclear complex said Tuesday that the radiation level around the plant's boundary is expected to exceed a self-imposed limit due to steps taken to address recently discovered leaks in underground radioactive water storage tanks.
Tokyo Electric Power Co. set a target to keep the site-boundary dose below 1 millisievert per year, but it now expects the dose at one point in the southern area to rise to up to 7.8 millisieverts, company officials said.
TEPCO unveiled the estimate as it decided to transfer around 23,000 tons of polluted water stored inside leaky
underground tanks to more reliable containers above ground. About a third of the liquid has already been pumped out from the troubled cisterns.
According to the estimate, the increase in radiation level will be highest at the plant boundary close to a location where part of the contaminated water will be transferred.
TEPCO will try to keep the radiation level lower by first using tanks that are further from the plant's boundary and by operating a new water treatment facility that can remove various radioactive substances.
At the Fukushima plant in northeastern Japan, a massive amount of radioactive water is accumulating as a result of continuing water injections to the three reactors that suffered meltdowns in the early stage of the nuclear crisis, triggered by the March 2011 earthquake and tsunami.