Fukushima
operators begin risky nuclear fuel rod removal
In
a highly risky undertaking Fukushima plant operators have finally
begun removing over 1,500 nuclear fuel rods from one of the four
reactors at its damaged nuclear power plant in northeastern Japan on
Monday.
RT,
18
November, 2013
During
the first transfers of the operation,
steel fuel rods were laid in a cooling pool in a damaged reactor
building. The portable pool holds 22 rods, with the operation being
likened to removing cigarettes from a squashed pack. While the first
group will take around two days to move, it could take up to a week
to move the cooling pool to a common storage pool in a different
building, TEPCO told Reuters. "We will continue
with the work from tomorrow and proceed, paying close attention to
safety," said TEPCO in the
statement.
It
is important to conduct the transfer as soon as possible as they are
being stored in an unstable building which could potentially collapse
in the event of another earthquake.
Unit 4 of the Fukushima
Daiichi plant was offline at the time of the 2011 catastrophic
earthquake and tsunami, which is why, unlike the other three, its
core didn't go into meltdown.
Hydrogen explosions blew the roof
off the building and severely damaged the structure, however. Keeping
so many fuel rods in a storage pool in the building poses a serious
safety risk, experts say.
With the help of robots and cranes,
the workers will attempt to cautiously transfer 1,331 spent fuel rods
and 202 new ones from the damaged reactor pool to a more reliable
storage facility. If these rods break or overheat, radioactive gases
could be released into the atmosphere, however, prompting a
self-sustained nuclear chain reaction.
According to the
operators of the plant, Tokyo Electric Power Co (TEPCO), all
necessary measures have been taken to contain the threat stemming
from the worst nuclear disaster since Chernobyl.
This
handout picture taken by Tokyo Electric Power Co (TEPCO) on November
18, 2013 shows a cask (C) of nuclear fuel being lifted and moved by
TEPCO workers as TEPCO started operations to remove fuel rods from a
pool at the unit four reactor building of TEPCO's Fukushima Dai-ichi
nuclear plant in the town of Okuma in Fukushima prefecture (AFP
Photo)
While
the full decommissioning of the plant is expected to take decades,
the company said it plans to remove 22 rods over the course of two
days. A giant crane equipped with a remote- controlled pincer will be
lowered into the pool and hook onto the rods, placing them inside a
91-ton cask which will be loaded on to a trailer and taken to a new
storage pool.
Earlier this week it was reported that three of
the spent fuel assemblies that will be pulled from the nuclear plant
on Monday were in fact damaged before the 2011 earthquake hit the
facility. TEPCO said the damaged assemblies - 4.5 meter high racks
with 50 to 70 rods of highly irradiated used fuel - wouldn’t be
lifted from the plant’s Reactor No. 4, Reuters reported.
In
an 11-page information sheet released in August, TEPCO informed that
one of the assemblies was actually damaged back in 1982, when it was
bent out of shape during a transfer.
Japan’s Nuclear
Regulation Authority has assigned an inspector to keep an eye on the
dangerous operation, as well as video monitoring of the removal site.
Meanwhile, targets for reducing radiation levels and
eradicating nuclear fallout in the areas still haven't been met, with
the radius of evacuation after the Fukushima nuclear meltdown larger
than the area of Hong Kong. Some areas will remain contaminated for
years to come, experts say. Part of the cleanup plan is to
decontaminate the surrounding towns and villages and follow new
guidelines by the International Center for Radiological Protection.
Nuclear
expert inspecting the unit four reactor building of the crippled
TEPCO's Fukushima Dai-ichi nuclear plant at Okuma town in Fukushima
prefecture (AFP Photo / TEPCO)
Major
setbacks have stalled TEPCO's handling of the crisis amid widespread
criticism. The utility was scheduled to begin the clean-up operation
earlier this month which had to be put off after the Japan Nuclear
Energy Safety Organization pressed for further safety checks.
A
recent special investigation by Reuters has revealed the distressing
conditions of working at the crippled Fukushima Daiichi plant,
which are aggravated by very low pay and questionable attitudes to
workers’ rights by sub-contractors involved in the numerous
projects.
TEPCO is in the process of decommissioning the entire
six-reactor Fukushima Daiichi plant after three reactors suffered
core meltdowns in March 2011. Moving the fuel assemblies in Reactor
No. 4 remains the top priority, as their height above ground appears
to be highly vulnerable to another earthquake.
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