From: Talking Point Memo
MARI YAMAGUCHI
August 23, 2013, 7:05 AM
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TOKYO (AP) — 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 sea.
Now, 2 1/2 years later, experts fear it is about to reach the
Pacific 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 used to store contaminated water
used to cool the reactor cores. That 300-ton (80,000 gallon) leak is
the fifth and most serious since the disaster of March 2011, 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 further into the sea. Most fishing in the area is already
banned, but fishermen in nearby Iwaki City were 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.
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 from the reactor 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 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 the 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 them have rubber seams intended
to last for only five years. Company spokesman Masayuki Ono said it
plans to build additional tanks with welded seams that are more
watertight, but will have to rely on rubber seams in the meantime.MORE
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