Spill-over
threat: Fukushima radioactive groundwater rises above barrier level
Radioactive
groundwater at the Japanese crippled nuclear plant has risen to
levels above a barrier built to try and contain it – with risks of
spilling over and reaching the ocean, Japanese media report.
RT,
3
August, 2013
The
Tokyo Electric Power Company (Tepco), which is responsible for
decommissioning the wrecked plant, estimated that contaminated
groundwater could reach the surface within three weeks, the Asahi
newspaper said.
One
of the biggest challenges facing Tepco is to try and contain the
radioactive water that cools the destroyed reactors as it mixes with
400 tonnes of fresh groundwater pouring into the plant every day.
The
company has been attempting to inject a chemical into the ground to
create a barrier to physically contain the groundwater, but the
method is only effective 1.8 meters below the surface, whereas data
from test wells shows that contaminated water has already risen to
one meter below the surface.
A
Tepco official said at the Friday meeting that equipment to pump out
the water would only be in place at the end of August. According to
local media reports, Tepco would need to pump out 100 tonnes of water
daily to prevent leakage into the ocean.
But
it is not clear where the contaminated water would be stored as more
than 85% of Fukushima’s 380,000 tonne storage capacity is already
full.
Workers
have already built more than 1,000 tanks to store mixed water, which
accumulates at the rate of an Olympic sized swimming pool every week.
The
tanks were built in a hurry from parts of old containers brought to
the site from closed down factories and then reassembled together
with new parts and the steel bolts holding the tanks together will
corrode in a few years.
Reporters
and Tokyo Electric Power Co workers look up the unit 4 reactor
building during a media tour at TEPCO's Fukushima Dai-ichi nuclear
plant in the town of Okuma, Fukushima prefecture in Japan on June 12,
2013. (AFP Photo)
Tepco
admits it has no idea how long the tanks will hold and estimates it
will need to double capacity over the next three years if it is to
contain all the water. After that it has no long term plan.
The
decommissioning engineers also want to stem the flow of groundwater
before it reaches the reactors by channeling it around the plant and
into the sea. The plan is to capture the groundwater at the elevated
end of the complex and divert it into a system of wells and pipes
into the ocean.
Local
fishermen are opposed to the idea and have rejected Tepco’s claims
that radiation levels would be negligible.
Some
of Tepco’s other efforts to stop radioactive water from leaking
into the sea include sinking an 800-meter-long steel barrier along
the coastline and even freezing the ground with technology used in
subway-tunnel construction.
Experts
from across the nuclear industry are not impressed and in January
Tepco found fish contaminated with high levels of radiation inside a
port at the plant.
As
well as the problem of contaminated water Tepco has also not solved
why the plant intermittently emits steam, if the repaired cooling
system will hold and why groundwater is seeping into the basement.
Tepco
admitted on Friday that an estimated 20 to 40 trillion Becquerel’s
of tritium may have flowed into the Pacific Ocean since May 2011.
Tritium has a half-life of twelve years. Tritium is only dangerous
when it is inhaled, ingested via food or water or absorbed through
the skin.
While
in March a rat shorted a temporary switchboard and cut power used to
cool spent uranium fuel rods for 29 hours.
A
worker checks radiation levels on the window of a bus during a media
tour at Japan's Fukushima Dai-ichi nuclear plant in the town of
Okuma, Fukushima prefecture on June 12, 2013. (AFP Photo)A worker
checks radiation levels on the window of a bus during a media tour at
Japan's Fukushima Dai-ichi nuclear plant in the town of Okuma,
Fukushima prefecture on June 12, 2013. (AFP Photo)
Economic
with the truth
Industry
experts and analysts are concerned at Tepco’s inability to get to
grips with the problems on the site and whether it can successfully
decommission the Fukushima plant.
“They
let people know about the good things and hide the bad things. This
culture of cover-up hasn’t changed since the disaster,” Atusushi
Kasai, a former researcher at the Japan Atomic Energy Institute, told
Japan Today.
Japan’s
nuclear energy watchdog expressed alarm at Tepco’s own admission
last month that radioactive water was leaking into the ocean as it
was in direct contradiction to what they had previously said.
“They
had said it wouldn’t reach the ocean, that they didn’t have the
data to show that it was going into the ocean,” said Masashi Goto,
a former nuclear engineer who has worked at plants run by Tepco.
Dale
Klein who chairs a third-party panel commissioned by Tepco to oversee
the reform of its nuclear division believes they are incompetent
rather than deliberately withholding information.
“The
plant is in a difficult physical configuration. I have some sympathy.
It’s not the fact that we’re having surprises – it’s the way
they are handling them. That’s where my frustrations are,” he
said.
Tepco’s
handling of the clean-up has further complicated Japan’s attempts
to restart its 50 nuclear power plants, almost all of which have been
idle since the disaster, forcing the country to import expensive
fossil fuels for its energy needs.
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