Radiation levels inside Fukushima's reactor 2 have reached
fatally high levels, and levels of water are far lower than
previously thought, experts say today.
A
radiation monitor indicates 131.00 microsieverts per hour
near the No.4 and No.3 buildings at the tsunami-crippled
Tokyo Electric Power Co. (TEPCO)'s Fukushima Daiichi
nuclear power plant in Fukushima prefecture February 28,
2012. (REUTERS/Kimimasa Mayama/Pool) The
current radiation levels are so high that even robots cannot
enter. Tokyo Electric Power Co. (TEPCO) says that new robots
and equipment will need to be developed to deal with the
lethal levels of radiation.
TEPCO spokesperson Junichi Matsumoto told the Associated
Press, "We have to develop equipment that can tolerate high
radiation" when locating and removing melted fuel during the
decommissioning.
At ten times the lethal dose, the radiation levels are at
their highest point yet.
At the current level of 73 sieverts, the data gathering
robots can only stand two to three hours of exposure. But,
Tsuyoshi Misawa, a reactor physics and engineering professor
at Kyoto University's Research Reactor Institute, told The
Japan Times, "Two or three hours would be too short. At least
five or six hours would be necessary." He added that "the
shallowness of the water level is a surprise, and the
radiation level is awfully high."
* * *
The Japan Times: Reactor 2 radiation too high for access
73 sieverts laid to low water; dose too high even for robots
Radiation inside the reactor 2 containment vessel at the
Fukushima No. 1 nuclear plant has reached a lethal 73
sieverts per hour and any attempt to send robots in will
require them to have greater resistance than currently
available, experts said Wednesday.
Exposure to 73 sieverts for a minute would cause nausea and
seven minutes would cause death within a month , Tokyo
Electric Power Co. said.
The experts said the high radiation level is due to the
shallow level of coolant water — 60 cm — in the containment
vessel, which Tepco said in January was believed to be 4
meters deep. Tepco has only peeked inside the reactor 2
containment vessel. It has few clues as to the status of
reactors 1 and 3, which also suffered meltdowns, because
there is no access to their insides.
The utility said the radiation level in the reactor 2
containment vessel is too high for robots, endoscopes and
other devices to function properly.
* * *
BBC News: Probe finds high radiation in damaged
Fukushima reactor
The operator of Japan's crippled Fukushima nuclear plant
has said damage to one of the reactors is much worse than
previously thought. [...]
On Tuesday workers managed to insert a probe into reactor
number two for only the second time and found damage worse
than expected.
Radiation was up to 10 times the fatal dose, the highest
yet recorded at the plant. The level of water cooling the
melted-down nuclear fuel was also far lower than expected.
The other two melted-down reactors, which are yet to be
examined closely, could be in an even worse state, our
correspondent adds.
