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Radioactive
Leaks in Japan Prompt Call for Overseas Help
The
operator of the crippled nuclear plant at Fukushima said it’s
losing its two-year battle to contain radioactive water leaks and
emphasized for the first time it needs overseas expertise to help
contain the disaster.
21
August, 2013
Tokyo
Electric Power Co. (9501) is grappling with the worst spill of
contaminated water since the March 2011 earthquake and tsunami caused
a meltdown at the Fukushima Dai-Ichi plant. The call for help from
Zengo Aizawa, a vice president at the utility, follows a leak of 300
metric tons of irradiated water. Japan’s nuclear regulator labeled
the incident “serious” and questioned Tepco’s ability to deal
with the crisis. Prime Minister Shinzo Abe made similar comments
earlier this month.
“We
will revamp contaminated-water management to tackle the issue at the
Fukushima Dai-Ichi plant and seek expertise from within and outside
of the country,” Aizawa said at a press conference last night in
Tokyo. “There is much experience in decommissioning reactors
outside of Japan. We need that knowledge and support.”
In
Vienna, the International Atomic Energy Agency said it’s prepared
to help. Besides radiated water, the site north of Tokyo has more
than 73,000 cubic meters of contaminated concrete, 58,000 cubic
meters of irradiated trees and undergrowth, and 157,710 gallons of
toxic sludge, according to the utility.
The
tanks holding highly radioactive water cover an area equal to 37
football fields, and the utility is clearing forest to make room for
more. There are 480 filters clogged with cesium. Each weigh 15 tons
and are warehoused in what the utility calls temporary storage,
though it will take hundreds of years for the radiation to decay.
‘Biggest
Concern’
Japan’s
nuclear watchdog has ratcheted up concern about more leaks of highly
radioactive water from the hundreds of storage tanks at the Fukushima
atomic plant.
The
possibility of leaks from other tanks “is the biggest concern,”
said Nuclear Regulation Authority Chairman Shunichi Tanaka at a press
conference yesterday. “This will need to be handled carefully on
the assumption that one incident could bring another.”
Late
last night, Tepco said water leaking from the storage tank probably
ran into the ocean. It cited high radiation readings in a drainage
ditch.
At
least one commissioner at the regulator questioned the accuracy of
data being released by Tepco and whether the incident had been fully
reported. The leak, along with a separate spill of 300 tons of
radioactive water a day into the Pacific Ocean, is raising doubts
about the utility’s ability to handle the 40-year task to
decommission the nuclear site.
Tepco’s
Effort
Tepco
is providing the regulator with information, company spokesman
Yoshikazu Nagai said by phone, declining to comment further. The
company’s shares fell as much as 15 percent in Tokyo yesterday,
their biggest intraday slide since June 5.
Japan’s
government has ordered an investigation into the safety of hundreds
of other tanks storing contaminated water in Fukushima, the site of
the world’s worst civilian nuclear disaster since the Chernobyl
reactor exploded in 1986.
There
are 226 tanks of similar bolted design to the leaking unit with the
same 1,000-ton capacity at the site, said Tatsuya Shinkawa, director
of the nuclear accident response office in the government’s Agency
for Natural Resources and Energy, which called for the probe.
Nuclear
incidents and accidents are ranked by order of severity on the
International Nuclear and Radiological Event Scale or INES, which has
seven categories and was set up by the International Atomic Energy
Agency.
Leaking
Tanks
On
Aug. 19, Tepco said about 300 tons of highly radioactive water had
leaked from a storage tank and was ranked as category one on INES,
the lowest.
Japan’s
NRA raised that to category three yesterday, or a “serious
incident.” The 2011 meltdown of the three reactors at Fukushima is
in the highest severity category of seven on the INES scale, the same
as Chernobyl.
“This
INES evaluation is based on the 300-ton leak, but I really wonder if
we can trust data provided by Tepco,” Toyoshi Fuketa, a
commissioner at the NRA, said at a meeting in Tokyo. “I really
wonder if we should judge based on Tepco’s data.”
In
two separate incidents this month, workers were exposed to
radioactive releases at the plant.
Prime
Minister Abe has said that Tepco alone isn’t able to handle the
clean-up, promising more government funds without detailing how
they’d be used.
Overseas
Concern
INES
is a means to measure nuclear accidents in terms of their effects on
health and the environment, according to the International Atomic
Energy Agency. Each of its seven steps represents a ten-fold increase
in severity. The IAEA last night said it takes the leaks in Japan
“seriously” and that it “remains ready to provide assistance on
request,” according to a statement on its website.
A
seven rating means there has been a “major release of radioactive
material with widespread health and environmental effects requiring
implementation of planned and extended countermeasures,” according
to the INES fact sheet.
Japan’s
regulator raised the INES rating on the water leak based on radiation
levels reported by the utility this week and on an evaluation of
measures at the plant to prevent such incidents. The IAEA will be the
final arbiter of where the leak will sit on the severity scale.
New York Times: “Potential for huge spill” of highly radioactive liquid from many Fukushima tanks at same time, says nuclear design expert
Top Officials: Leaks from more tanks are “the biggest concern… We are extremely concerned”
21
August, 2013
Fox
News,
Aug 21, 2013: Four other tanks of the same design have had similar
leaks since last year. The incidents have shaken confidence in the
reliability of hundreds of tanks that are crucial for storing what
has been a continuous flow of contaminated water. “We are extremely
concerned,” [Nuclear Regulation Authority deputy secretary-general
Hideka Morimoto] told reporters Wednesday.
New
York Times,
Aug 20, 2013: The new leak raises disturbing questions about the
durability of the nearly 1,000 huge tanks Tepco has installed about
500 yards from the site’s shoreline. [...] Hiroshi Miyano, an
expert in nuclear system design at Hosei University in Tokyo, said
that the tanks would be vulnerable to earthquake or tsunami, with the
potential for a huge spill. [...] At some point, Tepco will have no
choice but to start releasing some of the water, said Dr. Miyano, the
expert in nuclear system design. The continued problems have
heightened public scrutiny of Tepco and have made it harder to build
public consensus around any release of water, he said. “That just
makes the problem worse, with no viable solution,” he said.
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