TEPCO
to siphon off radioactive water from tunnels under Fukushima plant
The
operator of Japan’s crippled Fukushima Daiichi atomic plant plans
to start cleaning underground tunnels believed to be part of the
sources of radioactive materials poisoning the groundwater in the
area
RT,
6
January, 2014
The
Tokyo Electric Power Company (TEPCO) will first block the flow of
tainted water between the damaged buildings and the tunnels. Workers
will begin burying pipes in the ground to carry refrigerants in
January, NHK TV network reported. In April, they are set to start
draining the contaminated water from the tunnels.
Late
last month, TEPCO said it had found new leaks at the No. 1 reactor,
in addition to the previous ones discovered last earlier in December.
The latest incident on December 24 may have leaked around 225 tons of
radioactive water, Japan Daily Press reported. It turned out that the
water in that area contained Strontium-90, a radioactive isotope of
strontium produced by nuclear fission with a half-life of 28.8 years,
at a level as high as 440 becquerels per liter. The current temporary
limit for water to be released from the concrete boundaries is said
to be 10 becquerels of Strontium-90 per liter. A TEPCO representative
feared the water may have already seeped into the ground.
On
December 21, Tepco said it had found a record 1.9 million becquerels
per liter of beta ray-emitting radioactive substances at its No.2
reactor, the highest since the nuclear meltdown in March 2011. The
discovery was made after high levels of radioactive cesium were
detected in deeper groundwater at the No. 4 reactor. Previously, the
highest level recorded was 1.8 million becquerels at the No. 1
reactor on December 13. It's believed that the radioactivity in the
groundwater at reactor No. 2 has been rising since November.
Since
the outbreak of the Fukushima disaster in March 2011, leakage of
radiation-contaminated water has been the major threat to Japan’s
population and environment, as well as to the international
community.
The
chairwoman of the US Nuclear Regulatory Commission warned last month
that water exposed to radiation from the wrecked plant would soon
reach the US.
"The
highest amount of radiation that will reach the US is of two orders
of magnitude – 100 times – less than the drinking water
standard," Allison Macfarlane told Bloomberg. "So, if you
could drink the salt water, which you won’t be able to do, it’s
still fairly low."
According
to Ken Buesseler, a senior scientist at the Woods Hole Oceanographic
Institution, radiation released during explosions at the plant
meltdowns and during subsequent leaks of contaminated underground
water will reach mainland US shores by early 2014.
The
San Francisco Bay area city of Fairfax, California, passed a
resolution in early December calling for more testing of coastal
seafood and ways to reduce radiation emissions from Fukushima.
On
December 4, the UN nuclear watchdog, the International Atomic Energy
Agency (IAEA), advised the Fukushima Daiichi nuclear power plant to
consider dumping toxic water into the ocean after lowering the level
of radioactive materials to below the legal limit. Meanwhile,
according to a draft report released by officials on the Japanese
Industry Ministry's contaminated water panel, the Fukushima Daiichi
plant could run out of storage space for contaminated water within
two years. The report suggested covering the ground with asphalt to
reduce the rain inflow and building giant tanks with more capacity,
as well as installing special undersea filters to reduce the
radioactivity of water that leaks into the sea. Currently, 400 metric
tons of highly contaminated water is being produced at the site on a
daily basis, much of it later flowing to the sea.
To
tackle the problem, TEPCO has been running a test operation of an
advanced water processing machine, known as ALPS, which can remove
all radioactive materials except for tritium from tainted water. Its
operation could be key to reducing the high levels of radiation in
the water. TEPCO plans to clean up all of the tainted water through
ALPS by the end of March 2015. It says that over 300,000 tons of
radioactive water has been stored in 1,000 tanks at the Fukushima
plant, and that the amount will double within a few years.
In
July 2013 TEPCO acknowledged the fact that contaminated water has
been escaping from basements and trenches of the Fukushima plant into
the ocean. Since then, the operator reported two major leaks of
highly radioactive water into the ocean from storage tanks – a
300-ton leak in August and 430 liters in October.
Major
setbacks have stalled TEPCO's handling of the nuclear disaster amid
widespread criticism and calls to put Fukushima-related work under
government control. Earlier this week a former employee in the
facility said that one of the reasons for so many leaks could be the
cost-cutting measures applied by TEPCO, such as using duct tape and
wire nets to mend the leaking tanks.
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