UPDATE: More Problems at Quake-hit Nuclear Plant
By John Boyd
First Published July 2007
Critics say plant design regulations are too weak, predict
future catastrophe
PHOTO: Toyko Electric Power Co.
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25 July 2007—Ten days after a deadly earthquake
damaged the world’s most powerful nuclear complex, the
list of incidents and shut down has risen to 63 from the
50 known last week, and the Japanese
government is receiving strong
criticism. The Kashiwazaki-Kariwa
facility—located about 200 kilometers northwest of
Tokyo—is closed
indefinitely following a magnitude-6.8
earthquake and the discovery that the plant may be
sitting on an extension of a major fault line.
Critics say the government was lax in its inspection
of the fault line in the seabed near to where the
7-reactor, 8.21-gigawatt plant was constructed. Bowing
to the rising criticism, Akira Amari, minister of the
Ministry of Economy, Trade and Industry (METI), told the
Japanese press, Tuesday: “Asked whether [we] took
insufficient measures, I can’t help but say yes.” And in
an about-face, the government announced it would now
allow a team from the International Atomic Energy Agency
(IAEA) to inspect the damage at the facilities.
Academic experts are increasingly calling for the
government to take more responsibility for the design of
nuclear plants. Though the guidelines were revised last
year, “they are still insufficient and have several
loopholes,” according to Katsuhiko Ishibashi, a
professor and earthquake specialist at Kobe University.
“They need to be reviewed again,” he told the foreign
press in Tokyo last Friday. He added that unless
“fundamental improvements in nuclear plant earthquake
countermeasures are made, Japan would suffer from a
catastrophic [disaster] in the near future.”
The most recent problem found at the plant is damage
to a ceiling crane above the No. 6 reactor. The crane is
used to lift the lid of the pressure
container off the reactor. Until the
crane is fixed Tokyo Electric Power Co.
(TEPCO) says it will not be able to check the
reactor’s core.
Meanwhile TEPCO revealed that during the earthquake a
surveillance camera at the No. 3 reactor recorded waves
higher than 1 meter in the fuel storage pool. The water
level, normally 40 centimeters below the top of the
pool, eventually overflowed, some of the water finding
its way to the sea. Both TEPCO and METI reiterated,
however, that the impact of the spill and of a separate
leak of radioactive iodine into the air were negligible.
Ichiro Takekuro, executive vice president and nuclear
officer at TEPCO and a former director of the
Kashiwazaki-Kariwa complex, told reporters Tuesday that
the company was still “carrying out detailed inspection
of the facilities and equipment,” and would be
conducting a “detailed review of the facility’s design
and TEPCO’s response to the quake.”
The facility is closed indefinitely, leaving a
shortfall of 8.21 gigawatts just as the peak summer
demand sets in. According to Takekuro, TEPCO estimates a
maximum demand of 61.1 gigawatts, and it will be able to
secure 62.14 gigawatts without the Kashiwazaki-Kariwa
nuclear power station by starting up shuttered fossil
fuel plants.
On a personal note, Takekuro told reporters that the
last 10 days had been the busiest and most miserable of
his career. Given that detailed inspections are still
continuing and turning up further incidents on a daily
basis, the situation will likely get worse for Takekuro
and his colleagues before things improve.
See the 19 July IEEE Spectrum story on the plant
closing: “Quake-hit
nuclear plant shut down indefinitely.”
FOR MORE ABOUT EARTHQUAKES IN JAPAN
When the next big earthquake hits Tokyo, engineers
bet even a few seconds can save lives [see “How to
Master a Seismic Disaster,” IEEE Spectrum,
June 2007].
The Japan Meteorological Agency is responsible for
tracking earthquakes and other natural disasters in and
around Japan. On its Web site, you can see a plot of
earthquakes that have occurred there during the past
week: http://www.seisvol.kishou.go.jp/eq/weekly_map/japan/weekly.shtml.
For a more global view, see the U.S. Geological
Survey's weekly worldwide map of earthquakes. It shows
disturbances with magnitudes of 4.0 or greater (or 2.5
or greater within the United States and adjacent areas): http://earthquake.usgs.gov/eqcenter/recenteqsww.