海角大神

Radiation聽near a tank holding highly contaminated聽water聽at聽Japan's crippled聽Fukushima聽nuclear plant has spiked 18-fold, the plant's operator said on Sunday, highlighting the struggle to bring the crisis under control after more than two years.

Radiation聽of 1,800 millisieverts per hour - enough to kill an exposed person in four hours - was detected near the bottom of one storage tank on Saturday,聽Tokyo聽Electric Power Co , also known as Tepco, said.

An Aug. 22 readings measured聽radiation聽of 100 millisieverts per hour at the same tank. Japanese law has set an annual聽radiation聽exposure safety threshold of 50 millisieverts for nuclear plant workers during normal hours.

Last month, Tepco revealed that聽water聽from the tank was leaking.聽Japan's nuclear regulator later raised the severity of the leak from a level 1 "anomaly" to a level 3 "serious incident" on an international scale forradiation聽releases.

The聽Fukushima聽Daiichi power plant聽north of聽Tokyo聽was devastated by a tsunami on March 11, 2011 that resulted in fuel-rod meltdowns at three reactors, radioactive contamination of the air, sea and food and the evacuation of 160,000 people.

It sparked the worst nuclear crisis since聽Chernobyl聽a quarter of a century earlier.

While there were no new leaks found at the tank, a Tepco spokesman said another leak had been detected from a pipe connecting two other tanks nearby.

"We have not confirmed fresh leakage from the tank and聽water聽levels inside the tank has not changed," the Tepco spokesman said. "We are investigating the cause."

Tepco said the聽radiation聽measured was beta rays, which would be easier to protect against than gamma rays.

The Tepco spokesman also said the higher level of聽radiation聽from the latest reading was partly because investigators had used a measuring instrument capable of registering greater amounts of聽radiation.

Instruments used previously had only been capable of measuring聽radiation聽up to 100 millisieverts, but the new instruments were able to measure up to 10,000 millisieverts.

Radiation聽of 220 millisieverts was also recorded near an adjacent storage tank, where a reading of 70 had been registered last month.

Radiation聽of 230 millisieverts was detected from the new leak from the pipe connecting two nearby tanks, a new measurement of 70 was taken from another, separate storage tank.

Those tanks are built of steel plates stuck together by bolts - the same structure as the tank that was found last month to have leaked 300 tonnes of highly toxic聽water.

With no one seeming to know how to bring the crisis to an end, Tepco said last week it would invite foreign decommissioning experts to advise it on how to deal with the highly radioactive聽water聽leaking from the site.

Japan聽has also signalled it might dip into a $3.6 billion emergency reserve fund to help pay for the clean-up of a situation the chief cabinet secretary has described as "deplorable".

Its nuclear regulator has also expressed fear that the disaster was beyond Tepco's ability to cope in some respects.

Foreign Minister聽Fumio Kishida聽visited聽Chernobyl聽in聽Ukraine, the site of the 1986 disaster, hoping to apply lessons learned there to聽Fukushima.