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'Worst-case
scenario' at Fukushima
The
Japanese Nuclear Regulation Authority said the cascading series of
radioactive water leaks from the Fukushima plant is approaching a
worst case scenario.
UPI,
21
August, 2013
Tokyo
Electric Power Co., the plant's operator, this week confirmed about
79,000 gallons of radioactive water leaked from a storage tank. It
warned there may be hundreds more tanks like it on the site of the
2011 meltdown.
Chairman
of the Japan Nuclear Regulation Authority Shunichi Tanaka was quoted
Thursday by The Wall Street Journal as saying the situation was
alarming.
"We
cannot waste even a minute," he said. "This is what we have
been fearing."
The
nuclear watchdog raised the alert level to 3, a serious incident,
this week. The meltdown itself was categorized as a level 7 nuclear
event, the highest level.
Tepco
said Wednesday it was running out of space to store the 105,000
gallons of radioactive water pumped out of contaminated reactors each
day.
The
utility company said water hasn't yet reached the waters surrounding
the facility.
Atsunao
Marui, director of research at Japan's National Institute of Advanced
Industrial Science and Technology, said the situation is likely to
get worse.
"It's
important to think of the worst-case scenario," he said.
Fukushima
leak is 'much worse than we were led to believe'
A
nuclear expert has told the BBC that he believes the current water
leaks at Fukushima are much worse than the authorities have stated.
BBC,
22
August, 2013
Mycle
Schneider is an independent consultant who has previously advised the
French and German governments.
He
says water is leaking out all over the site and there are no accurate
figures for radiation levels.
Meanwhile
the chairman of Japan's nuclear authority said that he feared there
would be further leaks.
The
ongoing problems at the Fukushima plant increased in recent days when
the Tokyo Electric Power Company (Tepco) admitted that around 300
tonnes of highly radioactive water had leaked from a storage tank on
the site.
Moment
of crisis
The
Japanese nuclear energy watchdog raised the incident level from one
to three on the international scale that measures the severity of
atomic accidents.
This
was an acknowledgement that the power station was in its greatest
crisis since the reactors melted down after the tsunami in 2011.
But
some nuclear experts are concerned that the problem is a good deal
worse than either Tepco or the Japanese government are willing to
admit.
They
are worried about the enormous quantities of water, used to cool the
reactor cores, which are now being stored on site.
Some
1,000 tanks have been built to hold the water. But these are believed
to be at around 85% of their capacity and every day an extra 400
tonnes of water are being added.
"The
quantities of water they are dealing with are absolutely gigantic,"
said Mycle Schneider, who has consulted widely for a variety of
organisations and countries on nuclear issues.
"What
is the worse is the water leakage everywhere else - not just from the
tanks. It is leaking out from the basements, it is leaking out from
the cracks all over the place. Nobody can measure that.
"It
is much worse than we have been led to believe, much worse,"
said Mr Schneider, who is lead author for the World Nuclear Industry
status reports.
At
news conference, the head of Japan's nuclear regulation authority
Shunichi Tanaka appeared to give credence to Mr Schneider's concerns,
saying that he feared there would be further leaks.
``We
should assume that what has happened once could happen again, and
prepare for more. We are in a situation where there is no time to
waste," he told reporters.
The
lack of clarity about the water situation and the continued attempts
by Tepco to deny that water was leaking into the sea has irritated
many researchers.
Dr
Ken Buesseler is a senior scientist at Woods Hole Oceanographic
Institution who has examined the waters around Fukushima.
"It
is not over yet by a long shot, Chernobyl was in many ways a one week
fire-explosive event, nothing with the potential of this right on the
ocean."
"We've
been saying since 2011 that the reactor site is still leaking whether
that's the buildings and the ground water or these new tank releases.
There's no way to really contain all of this radioactive water on
site."
"Once
it gets into the ground water, like a river flowing to the sea, you
can't really stop a ground water flow. You can pump out water, but
how many tanks can you keep putting on site?"
Several
scientists also raised concerns about the vulnerability of the huge
amount of stored water on site to another earthquake.
Water
from the storage tanks has seeped into the groundwater and then into
the sea. Efforts to use a chemical barrier to prevent sea
contamination have not worked.
New
health concerns
The
storage problems are compounded by the ingress of ground water,
running down from the surrounding hills. It mixes with radioactive
water leaking out of the basements of the reactors and then some of
it leaches into the sea, despite the best efforts of Tepco to stem
the flow.
Some
of the radioactive elements like caesium that are contained in the
water can be filtered by the earth. Others are managing to get
through and this worries watching experts.
"Our
biggest concern right now is if some of the other isotopes such as
strontium 90 which tend to be more mobile, get through these
sediments in the ground water," said Dr Buesseler.
"They
are entering the oceans at levels that then will accumulate in
seafood and will cause new health concerns."
There
are also worries about the spent nuclear fuel rods that are being
cooled and stored in water pools on site. Mycle Schneider says these
contain far more radioactive caesium than was emitted during the
explosion at Chernobyl.
"There
is absolutely no guarantee that there isn't a crack in the walls of
the spent fuel pools. If salt water gets in, the steel bars would be
corroded. It would basically explode the walls, and you cannot see
that; you can't get close enough to the pools," he said.
The
"worsening situation" at Fukushima has prompted a former
Japanese ambassador to Switzerland to call for the withdrawal of
Tokyo's Olympic bid.
In
a letter to the UN secretary general, Mitsuhei Murata says the
official radiation figures published by Tepco cannot be trusted. He
says he is extremely worried about the lack of a sense of crisis in
Japan and abroad.
This
view is shared by Mycle Schneider, who is calling for an
international taskforce for Fukushima.
"The
Japanese have a problem asking for help. It is a big mistake; they
badly need it."
New
radiation readings suggest more Fukushima tank leaks
Excessive
radiation levels have been detected next to the vast storage tanks
containing the highly-contaminated water used to cool reactors at the
damaged Fukushima power plant. One such tank already leaked earlier
this week.
RT,
22
August, 2013
The
announcement was made by Fukushima operator Tokyo Electric Power Co
(TEPCO), which began to check its 300 storage tanks after 300 tons of
contaminated water escaped from one of them on Wednesday.
The
contaminated water that leaked on Wednesday contains an unprecedented
80 million Becquerels of radiation per liter, according to the
company. The norm is a mere 150 Bq.
The
puddle that formed around the damaged tank is emitting radiation of
100 Millisieverts per hour, as a probe has been taken about half a
meter from the water, reported Kyodo News. The traces of
radioactivity were detected in a drainage stream.
“We
have finished pumping out water from the troubled tank, while we have
continued removing the soil soaked by the water,” Numajiri said.
“We cannot rule out the possibility that part of the contaminated
water flowed into the sea.”
Japan’s
Nuclear Regulation Authority (NRA) commissioners raised the severity
of the latest Fukushima leak to Level Three, which is considered a
‘serious radiation incident’ on the International Nuclear Event
Scale (INES) for radiological releases. The alert was raised from
Level One, which indicates an ‘anomaly’. Level Seven is the most
dangerous radiation status.
"Judging
from the amount and the density of the radiation in the contaminated
water that leaked ... a Level 3 assessment is appropriate," said
the document used during Wednesday’s weekly meeting of the NRA.
NRA
Chairman Shunichi Tanaka on Wednesday voiced concern that there could
be similar leaks from other containers.
“We
must carefully deal with the problem on the assumption that if one
tank springs a leak the same thing can happen at other tanks,” he
said.
One
of the main difficulties for TEPCO in handling the nuclear plant
damaged in 2011 Tsunami is what to do with the water used to cool the
reactor. The liquid is stored in some 1,000 reactors.
Since
the melted cores of the three destroyed reactors have burnt through
the concrete basement of the reactor zone, radioactive water is
seeping into the surrounding soil.
In
July, TEPCO reported officially for the first time that the
radioactive groundwater had been leaking outside the plant, which is
located close to the Pacific coast.
Radioactive
water leaking from Fukushima plant
CNN
https://www.youtube.com/watch?feature=player_embedded&v=Y5SZKsndqTU
"The short-term solution is storage. There is no long-term solution"
"The short-term solution is storage. There is no long-term solution"
How
Long Will Fukushima Be ALLOWED To Continue Dumping Radiation Into The
Pacific Ocean?
NHK
News
Japan Races To Contain Worst Fukushima Spill Since Meltdown
22
August, 2013
TOKYO—Japan
is scrambling to contain its worst spill of contaminated water from
the crippled Fukushima Daiichi nuclear plant since its meltdown more
than two years ago, drawing fresh scrutiny to what experts say
remains its shortsighted handling of the site.
On
Wednesday, Japan's nuclear watchdog declared that the plant had
suffered a "serious incident"—level "3" on an
international scale—after operator Tokyo Electric Power Co. 9501.TO
+2.43% said that some 300 metric tons, or 79,000 gallons, of highly
radioactive water had leaked from a hastily built storage tank and
warned that roughly 300 more of the potentially leaky tanks existed.
It was the first declaration of a nuclear incident in Japan since
regulators classed the meltdowns at the Fukushima Daiichi plant a
level "7"—the highest—in 2011.
Radioactive
water seeped from one of some 300 quickly built tanks, Tepco said
this week. Leaks in underground storage pools had forced Tepco to
move the water above ground.
"This
is what we have been fearing," said Shunichi Tanaka, chair of
Japan's Nuclear Regulation Authority, answering questions about the
leak at a news conference. "We cannot waste even a minute"
to take action.
Behind
the leak is a more serious problem: During the past few months it has
become clear that Tepco has lost control over the flow of water at
the plant and that the problem is escalating, nuclear experts say.
Every
day, the utility has to find a place to store around 400 tons of
contaminated water that it pumps out of the radioactive reactor
buildings, and Wednesday it warned that it is fast running out of
space. Storage tanks set up on the fly during plant emergencies have
started springing leaks, and Tepco can't replace them with sturdier
ones fast enough. Groundwater-contamination levels are spiking at the
seaward side of the plant, and water is flowing into the ocean past a
series of walls, plugs and barriers that have been flung up to impede
its passage.
That
lack of control is a big liability, said Kathryn Higley, a specialist
in the spread of radiation and head of the Department of Nuclear
Engineering and Radiation Health Physics at Oregon State University,
who spent a week in Fukushima earlier this year.
"You
have to find ways to control water coming through the site," Ms.
Higley said. "With any sort of accident, you want to control the
timing of what's released and when it gets released."
So
far, the levels of radioactivity that have escaped to the outside
remain relatively low, but some experts warn they may not stay that
way—particularly as equipment ages and the heavy-duty work of
dismantling the damaged buildings and removing the melted fuel rods
proceeds. The radioactivity of the water in the most recent leak was
so high that workers couldn't get close enough to search for the
cause until the remaining fluid in the tank was removed.
Tepco
said it doesn't think that water has flowed into the sea but can't
say for sure. Some of the flooded reactor basements are similarly too
hot to approach, and it is still not clear where the melted fuel
cores are, or in what state.
"In
the future there might be even more heavily contaminated water coming
through," said Atsunao Marui, head of the groundwater research
group at Japan's National Institute of Advanced Industrial Science
and Technology and a member of a blue-ribbon panel set up in May to
figure out ways of managing the radioactive water. "It's
important to think of the worst-case scenario."
Mr.
Marui and others say the biggest reason for the scramble now is that
Tepco—and the government bodies that oversee it—weren't planning
far enough ahead and waited too long to respond to problems they
should have seen coming long ago.
Fukushima
Daiichi was built some 40 years ago on the site of a river that was
diverted in order to situate the plant, Mr. Marui says. It should
have been clear that lots of groundwater would be rushing through the
site, he says, and that any walls or barriers built on the seaward
side would soon be overwhelmed—something that, indeed, has happened
in recent weeks.
"They're
only responding after the fact—they're not thinking ahead,"
said Hajimu Yamana, a professor of nuclear engineering at Kyoto
University who earlier this month was named chair of a new institute
charged with helping develop measures to tackle the longer-term work
of dismantling the plant. "As an expert, I was watching it with
frustration."
Tepco
says it is changing its ways, while the government and nuclear
regulator have set up three separate committees of experts charged
with helping fix Fukushima Daiichi's water problems. Those fixes have
included everything from a plan to drain highly radioactive water
from a set of trenches near the sea to a massive wall of ice that
would surround the damaged reactors and keep water out. Prime
Minister Shinzo Abe earlier this month promised money and resources
to help.
But
even with the extra firepower, Tepco and its helpers are playing
catch-up, and critics say response remains confused, shortsighted and
slow.
"We
have not remained idle, but we admit that we have been reactive,"
Zengo Aizawa, Tepco executive vice president for nuclear public
relations, said at a news conference Wednesday, during which the
company was grilled about the leak. "We are very, very sorry for
causing concern."
Tatsuya
Shinkawa, director of the Ministry of Economy, Trade and Industry's
Nuclear Accident Response Office said METI, which oversees Tepco,
should have been faster at figuring out how quickly the situation at
Fukushima Daiichi was changing in recent months.
This
aerial view photo taken Tuesday shows the Fukushima Daiichi nuclear
power plant and its contaminated water storage tanks at bottom.
Although
Tepco had been struggling to contain contaminated water since the
March 2011 accident, when a massive earthquake and tsunami knocked
out power at the plant and caused the three active reactors to melt
down, the problems there came into focus again this April. That is
when three vast underground storage pools for contaminated water were
found to have sprung leaks, forcing Tepco to move tens of thousands
of tons of radioactive water to tanks above ground.
METI
decided it had better take a hard look at the utility's plans to
control water at Fukushima Daiichi, Mr. Shinkawa said.
What
it found, he said, is that Tepco's plans had already fallen behind
the situation on the ground. Tepco estimates that around 1,000 tons
of groundwater flow through the site every day, some 400 tons of
which goes into the radioactive reactor buildings. It is mixed with
another 400 tons injected daily to keep the melted fuel cores cool.
The company was pumping out that water every day, recycling half and
putting the other half in storage, while it hurried to figure out
ways of keeping the groundwater from getting contaminated in the
first place, Tepco and government officials said.
But
one project—which called for diverting water to the sea before it
could hit the contaminated buildings by pumping it out from a string
of wells on the landward side of the site—hit opposition from local
fishermen, who didn't like the idea of dumping any water from
Fukushima Daiichi into the ocean. Given that sentiment, the ministry
judged that another idea for a similar set of pumps closer to the
damaged structures was less likely to succeed, Mr. Shinkawa said.
In
May, METI set up a 20-person committee of experts—the one Mr. Marui
is on—and asked them to come up with a better plan.
Mr.
Marui said that one measure Tepco was taking—the construction of a
giant sea wall hugging the coast by the damaged reactors—struck him
and others on the committee as misguided. Since it was possible that
contaminated water was already leaking into waters near the plant,
the wall should have been built further out, he says. More important,
the first wall built should have been on the landward side of the
plant to keep water out of the most contaminated area, he says.
By
the end of May, the group came up with a proposal for such a wall,
made by freezing the ground in a 1.4-kilometer (0.9-mile) ring around
the reactor buildings, and passed the task of honing the idea to a
second expert's group.
What
the groups didn't know, however, was that on the ground, the
situation had worsened again. In May, Tepco started to detect
elevated levels of radiation in wells very close to the coast,
suggesting that groundwater contamination had advanced farther than
previously thought. Tepco admitted the delay when it finally
announced its findings in early July.
As
news on the spiking radiation readings trickled out from Tepco in
July, regulator NRA and its chairman, Mr. Tanaka, went on the attack,
demanding faster action and more information. It stated publicly it
suspected the tainted water was already pouring into the ocean. By
the end of July, the NRA decided it had to form its own group to
propose solutions for Fukushima Daiichi's water problems. That
12-member group, composed mostly of experts, regulators and Tepco
officials, met for the first time Aug. 2.
"This
really isn't something we were supposed to do," said Shinji
Kinjo, director of the NRA's Fukushima Daiichi accident measures
office, explaining that the regulator's job is to be an umpire, not a
player. "But we just couldn't sit by and do nothing."
METI's
experts committee finally held another meeting on Aug. 8, deciding to
review its previous proposals and come up with another report by the
end of September. The NRA group took charge of supervising two of
Tepco's three emergency water-contamination measures—such as the
plan to remove highly toxic water from seaside trenches—and METI's
group took over one, as well as longer-term steps.
Mr.
Marui said that the big size of METI's group means it takes longer to
decide things and that there is still a debate raging about the plan
for ground-freezing, which is an expensive technology that is never
been used on such a scale. One of Japan's best-known ground-freezing
companies decided not to bid for a feasibility study at the site; the
company thought its expertise, in freezing smaller amounts of ground
for tunnels, wouldn't be applicable for such a different kind of job,
someone familiar with the company's thinking said.
What's
really needed is a plan to divert the course of the water, that is
still trying to flow in its old river bed, Mr. Marui said.
"We
have to plan systematically," Mr. Marui said. "Not just
figure out what's needed at that moment."
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