Radioactive
Groundwater at Fukushima Nears Pacific
Deep
beneath Fukushima's crippled nuclear power station, a massive
underground reservoir of contaminated water that began spilling from
the plant's reactors after the 2011 earthquake and tsunami has been
creeping slowly toward the Pacific.
23
August, 2013
Now,
2 1/2 years later, experts fear it is about to reach the ocean and
greatly worsen what is fast becoming a new crisis at Fukushima: the
inability to contain vast quantities of radioactive water.
The
looming crisis is potentially far greater than the discovery earlier
this week of a leak from a tank that stores contaminated water used
to cool the reactor cores. That 300-ton (80,000-gallon) leak is the
fifth and most serious from a tank since the March 2011 disaster,
when three of the plant's reactors melted down after a huge
earthquake and tsunami knocked out the plant's power and cooling
functions.
But
experts believe the underground seepage from the reactor and turbine
building area is much bigger and possibly more radioactive,
confronting the plant's operator, Tokyo Electric Power Co., with an
invisible, chronic problem and few viable solutions. Many also
believe it is another example of how TEPCO has repeatedly failed to
acknowledge problems that it could almost certainly have foreseen —
and taken action to mitigate before they got out of control.
It
remains unclear what the impact of the contamination on the
environment will be because the radioactivity will be diluted as it
spreads farther into the sea. Most fishing in the area is already
banned, but fishermen in nearby Iwaki City had been hoping to resume
test catches next month following favorable sampling results. Those
plans have been scrapped after news of the latest tank leak.
"Nobody
knows when this is going to end," said Masakazu Yabuki, a
veteran fisherman in Iwaki, just south of the plant, where scientists
say contaminants are carried by the current. "We've suspected
(leaks into the ocean) from the beginning. ... TEPCO is making it
very difficult for us to trust them."
To
keep the melted nuclear fuel from overheating, TEPCO has rigged a
makeshift system of pipes and hoses to funnel water into the broken
reactors. The radioactive water is then treated and stored in the
aboveground tanks that have now developed leaks. But far more leaks
into the reactor basements during the cooling process — then
through cracks into the surrounding earth and groundwater.
About
1,000 tons of underground water from the mountains flows into the
plant compound each day, of which 400 tons seep into the reactor and
turbine basements and get contaminated. The remaining 600 avoids that
area, but at least half of it is believed to eventually come in
contact with contamination elsewhere before entering the sea,
according to an estimate by Japan's Agency for Natural Resources and
Energy.
Scientists,
pointing to stubbornly high radioactive cesium levels in
bottom-dwelling fish since the disaster, had for some time suspected
the plant was leaking radioactive water into the ocean. TEPCO
repeatedly denied that until last month, when it acknowledged
contaminated water has been leaking into the ocean from early in the
crisis. Even so, the company insists the seepage is coming from part
of a network of maintenance tunnels, called trenches, near the coast,
rather than underground water coming out of the reactor and turbine
area.
"So
far, we don't have convincing data that confirm a leak from the
turbine buildings. But we are open to consider any possible path of
contamination," said TEPCO spokesman Yoshimi Hitosugi.
The
turbine buildings at the Fukushima Dai-ichi plant are about 150
meters (500 feet) from the ocean. According to a Japan Atomic Energy
Agency document, the contaminated underground water is spreading
toward the sea at a rate of about 4 meters (13 feet) a month.
At
that rate, "the water from that area is just about to reach the
coast," if it hasn't already, said Atsunao Marui, an underground
water expert at the National Institute of Advanced Industrial Science
and Technology who is on a government committee studying the
contaminated water problem. "We must contain the problem as
quickly as possible."
TEPCO,
nationalized and burdened with the astronomical cleanup costs, has
been criticized for repeatedly lagging in attempts to tackle leakage
problems. As a precautionary step, it has created chemical blockades
in the ground along the coast to stop any possible leaks, but experts
question their effectiveness. After a nearly two-year delay,
construction of an offshore steel wall designed to contain
contaminated water has begun.
The
utility has also proposed building frozen walls — upside down
comb-shaped sticks that refrigerate surrounding soil — into the
ground around the reactor areas, but that still has to be tested and
won't be ready until 2015 if proved successful.
Prime
Minister Shinzo Abe earlier this month announced that the government
would intervene and provide funding for key projects to deal with the
contaminated water problem.
"This
is a race against the clock," said Toyoshi Fuketa, a
commissioner on Japan's Nuclear Regulation Authority.
Compounding
TEPCO's problems is the new leak discovered this week. Most of the
300 tons is believed to have seeped into the ground, but some may
have escaped into the sea through a rainwater gutter, said Zengo
Aizawa, the company's executive vice president.
That,
too, may be a harbinger of more problems ahead.
Some
1,000 steel tanks built across the plant complex contain nearly
300,000 tons (300 million liters, 80 million gallons) of partially
treated contaminated water. About 350 of the tanks have rubber seams
intended to last for only five years. TEPCO spokesman Masayuki Ono
said the company plans to build additional tanks with welded seams
that are more watertight, but will have to rely on rubber seams in
the meantime.
Shinji
Kinjo, a regulatory official in charge of the Fukushima disaster,
said the rubber-seam tanks were mostly built in a rush when the
contaminated water problem started, and often lacked adequate quality
tests and require close attention.
Workers
spotted two more questionable tanks during an inspection Thursday.
After
his inspection Friday, Fuketa, the regulatory commissioner, said that
the plant's twice-daily leak-spotting patrols were "sloppy,"
and that there were hardly any protective measures taken in
anticipation of a potential tank leak.
"It's
like a haunted house, one thing happening after another," said
Nuclear Regulation Authority Chairman Shunichi Tanaka, referring to
the spate of problems at the plant. "But we must take any steps
that would reduce risks to avoid a fatal accident."
Leaks
of highly contaminated water from the aboveground tanks aggravate the
groundwater problem.
"Any
contamination in the groundwater would eventually flow into the
ocean. That is very difficult to stop even with barriers," said
Ken Buesseler, a marine chemist at the Woods Hole Oceanographic
Institution in Massachusetts. He found that radioactive cesium levels
in most fish caught off the Fukushima coast hadn't declined in the
year following the March 2011 disaster, suggesting that the
contaminated water from the reactor-turbine areas is already leaking
into the sea.
But
TEPCO hasn't provided the details he and other scientists need to
further assess the situation.
TEPCO’s
Fukushima inspections inadequate – Japan nuclear regulator
Japan’s
nuclear regulator has concluded that the Fukushima nuclear plant’s
operator was inadequate in its inspection of radioactive water tanks
after news of yet another leak. TEPCO earlier admitted it will now
require international help.
RT,
23
August, 2013
On
Friday, the Nuclear Regulation Authority (NRA) Commissioner Toyoshi
Fuketa visited the destroyed Fukushima Daiichi nuclear power plant to
inspect the ongoing radioactive cleanup efforts. Fuketa’s comments
follow those of the NRA chairman Shunichi Tanaka, who earlier this
week worried that the makeshift giant radioactive containers were
prone to failure.
"Fundamentally,
for a facility holding that kind of radioactive water, they did not
take action that foresaw the risks of possible leaks," Fuketa
said at a press briefing in Hirono. "On top of that – and this
is an impression I had before my visit – I can't help but say that
the inspections were careless."
The
plant operator said on Thursday that a new radiation spill has been
detected near the storage tanks, which sparked fears of newer leaks
before the old ones had been dealt with.
Furthermore,
the company has been accused of failing to properly document
inspections, leading to misspent resources and problems cropping up
that should have been noticed before, according to Fuketa.
Japan
has decided to raise the gravity 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 most dangerous, Level Seven, has only been applied
twice – for the Chernobyl catastrophe in 1986 and for the meltdown
of three reactors at the Fukushima plant.
TEPCO
has also now admitted it will be seeking international expertise to
help out with the leaks.
"Many
other countries outside of Japan have experienced decommissioning
reactors, so we hope we can consult them more and utilize their
experience,” TEPCO’s vice-president, Zengo Aizawa, said at a news
conference on Wednesday night.
"In
that sense we need support - not only from the Japanese government,
but from the international community - to do this job."
The
UN’s International Atomic Energy Agency (IAEA) said that it was
ready to help out, if needed, and that it viewed the situation
“seriously,” just as China was saying it was “shocked” to
hear that radioactive water leaks are still continuing. The neighbor
has urged Japan to provide it with information “in a timely,
thorough and accurate way.”
Almost
two-and-a-half years since a lethal combination of a tsunami and an
earthquake crippled the power plant and caused a multitude of
subsequent problems, TEPCO is faced with its most serious problem
yet. This is after the recent discovery that radioactive water has
been leaking from the plant’s storage tanks into the Pacific at an
alarming rate of 300 tons a day.
An
aerial view shows Tokyo Electric Power Co. (TEPCO)'s tsunami-crippled
Fukushima Daiichi nuclear power plant and its contaminated water
storage tanks (bottom) in Fukushima, in this photo taken by Kyodo
August 20, 2013. (Reuters/Kyodo)
Numerous
contingency measures have been thought of for the problems that keep
cropping up continuously in different parts of Fukushima –
including leaking radioactive water, as well as a danger that Reactor
4 would collapse on itself. The structure holds upwards of 1,300
nuclear fuel rods containing 14,000 times the amount of radiation
that the Hiroshima bomb released.
A
never-before-attempted operation is in the works. It will involve the
manual removal of nuclear fuel rods from Reactor 4 by way of a
manually-operated crane – not by computer. Any mistakes could lead
to contamination on an unprecedented scale. All this is happening at
a time when the soil beneath Reactor 4 is slowly sinking.
The
tanks, which are used to keep the coolant that prevents the damaged
reactors from overheating dangerously, are considered to be
unsuitable because they were made for other industrial purposes. They
were adapted following the emergency, but they are nearly full.
TEPCO
estimates that it has already reached 85 percent capacity, although
plans to create a more permanent facility have so far not
materialized. The latest leak was the fifth time that toxic water
escaped from a basin.
The
operator has been slow in measuring the levels of radioactive
elements that have flowed out of the station, as well as publishing
its data. TEPCO finally revealed this month that highly unsafe
tritium and cesium levels had been detected in the seawater near the
plant. A concentration of these elements could damage the marine
environment and build up in marine life, possibly endangering humans
further up the food chain.
The
catastrophe of March 11, 2011, caused the meltdown of nuclear fuel
rods at three of the plant’s reactors, leading to a contamination
of air and sea, as well as crippling the region’s agriculture and
fishing activities, gravely damaging the economy for years to come.
On top of this, costs required for the cleanup, as well as to sustain
the nation’s needs and compensation payouts, are projected to be in
the billions – a fact that has recently caused the Japanese
government to step in and start contributing money to TEPCO’s
efforts.
The
Fukushima nuclear meltdown has been called the worst radioactive
event since the Chernobyl nuclear disaster of 1986. And with
protracted cleanup efforts expected to last decades, by multiple
estimates, any misstep could lead to a cascading chain of dangerous
radioactive events, fallout researcher Christina Consolo told RT. She
made special reference to the upcoming operation for the manual
removal of fuel rods from Reactor 4.
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