Over the past half century,
seismic history knowledge has steadily improved and serious risks have been
identified. What this means is that the
giant tsunami experienced at Fukushima and the Honshu coast was not a surprise
and had occurred roughly every thousand years.
As reported below, the chance of such an event was easily at five
percent and realistically far higher since the last such quake was in the
distant past. In fact a better figure
since centuries had passed, would have been between 25% to 60%.
I do not fault builders for not
knowing the risks when the plants were built.
Yet even they had options available to ameliorate tsunami risk which was
never zero. By the way, that risk is not
zero on any coast line even when it is at least extremely unlikely. This never described the coast of Honshu .
What is galling, simply placing
all reactors on the East coast of Honshu would
have nicely cut the risks hugely except for some local exceptions easily
identified. That could have been done
from the very beginning.
The real problem is that the
problem was identified and then ignored.
I have already posted that the emergency back up power could easily have
been situated in a far safer locale out of harms way or placed in a strong
steel beam building on higher floors. It
was that cheap and simple to back up against a possible inundation.
The lesson is that the plants
could have survived had back up power been available to tap quickly. Instead they could only watch a melt down.
I think all nuclear power plants
need to be carefully reviewed in terms of the practical preservation of support
in the event of a natural disaster however unlikely it may be simply because
plenty of the solutions are cheap and easy and that particularly applies to the
backup power system. It should be
painfully obvious that a well placed bomb that took out the back up and grid access
could have created just as much damage.
Not all disasters are natural.
Vindicated Seismologist Says Japan Still Underestimates Threat
to Reactors
By Jason Clenfield - Nov 21, 2011 7:01 AM PT
Japan Atomic Power Co.'s Tsuruga nuclear power station in Tsuruga city,
Fukui prefecture, Japan .
Reactor 1 at the Tsuruga plant, which had its license extended for 10 years in
2009, is one of 13 on Wakasa bay, a stretch of Sea of
Japan coast that is home to the world’s heaviest concentration of
nuclear reactors. Photographer: Tomohiro Ohsumi/Bloomberg
Sept. 22 (Bloomberg) -- Robert Geller, a professor at Tokyo
University's Department of Earth and Planetary Sciences, talks about Japan's
preparedness for the March 11 earthquake and tsunami that left about 19,000
people dead or missing and caused the worst nuclear crisis since Chernobyl.
Geller speaks with Susan Li on Bloomberg Television's "First Up."
(Source: Bloomberg)
Dismissed as a “nobody” by Japan’s nuclear industry,
seismologist Katsuhiko Ishibashi spent two decades watching his predictions of
disaster come true: First in the 1995 Kobe earthquake and then at Fukushima. He
says the government still doesn’t get it.
The 67-year-old scientist recalled in an interview how his boss marched
him to the Construction Ministry to apologize for writing a 1994 book
suggesting Japan ’s
building codes put its cities at risk. Five months later, thousands were killed
when a quake devastated Kobe city. The book, “A Seismologist Warns,”
became a bestseller.
That didn’t stop Haruki Madarame, now head of Japan ’s Nuclear
Safety Commission, from dismissing Ishibashi as an amateur when he warned
of a “nuclear earthquake disaster,” a phrase the Kobe University
professor coined in 1997. Ishibashi says Japan still underestimates the risk
of operating reactors in a country that has about 10 percent of the world’s
quakes.
“What was missing -- and is still missing -- is a recognition of the
danger,” Ishibashi said, seated in a dining room stacked with books in his
house in a Kobe
suburb. “I understand we’re not going to shut all of the nuclear plants, but we
should rank them by risk and phase out the worst.”
Among Japan ’s
most vulnerable reactors are some of its oldest, built without the insights of
modern earthquake science, Ishibashi said. It was only in the last four years
that Japan Atomic Power Co. recognized an active fault line running under its
reactor in Tsuruga, which opened in 1970 about 120 kilometers (75 miles)
northeast ofOsaka and
close to a lake that supplies water to millions of people in the region.
Japan Atomic is reinforcing the plant to improve quake tolerance and
believes it’s safe despite the discovery of new active faults lines in 2008,
Masao Urakami, a Tokyo-based spokesman for the utility, said.
“We can’t respond to every claim by every scientist,” he said.
“Standards for seismic ground motion are not decided arbitrarily, but are based
on findings by experts assigned by the government.”
Reactor 1 at the Tsuruga plant, which had its license extended for 10
years in 2009, is one of 13 on Wakasa bay, a stretch of Sea of Japancoast that is
home to the world’s heaviest concentration of nuclear reactors. The area is
riddled with fault lines found in the last three or four years, according to
Ishibashi.
In the first annual review of energy policy since
the Fukushima
disaster, the government on Oct. 28 approved a white paper calling for reduced
reliance on nuclear power. The report also omitted a section on nuclear power
expansion that was in last year’s review.
The government “regrets its past energy policy and will review it with
no sacred cows,” the report said.
The white paper needs to be followed with action, Ishibashi said.
“Changing the energy policy is a good thing, but I really do wonder if there
will be follow-through,” he said.
Opinion polls show the Fukushima
disaster has turned the majority of Japanese against nuclear power. Companies,
meantime, are worried about higher costs and unstable electricity supply. The
country has no oil reserves and 30 percent of Japan ’s electricity supply came
from atomic energy before March 11.
Threat to Move
Komatsu Ltd. (6301), the world’s No. 2 maker of construction
machinery, has said it will move overseas if stable electricity supply isn’t
guaranteed. Prime Minister Yoshihiko Noda said
on Sept. 2 that some reactors shut down after the March disaster will have to
restart to keep the economy going.
“These plants are a calculated risk,” says Tom Jordan, director of the Southern California
Earthquake Center in Los
Angeles. “Japan
has been reasonably thoughtful but they obviously have problems with
earthquakes and they have underestimated the risks. Still you have to ask the
question: what is the risk of depending on other sources of power?”
Flipping through binders of press clippings in a black T- shirt and
grey slacks, Ishibashi said he still remembers his fear of quakes when he was a
boy. He slept with a flashlight next to his pillow in case he had to escape in
the night.
While in college, a magnitude 7.5 earthquake off Japan ’s coast killed dozens in the city ofNiigata and sent shock waves through Ishibashi’s
apartment in Tokyo.
Experts Needed
“There was a radio broadcast that night saying Japan didn’t have enough earthquake
experts,” he said, adjusting his steel-rimmed glasses. “I decided I’d do that.”
It was 1964. Modern seismology was getting started and Japan was
halfway through building its first nuclear reactor. By the time Ishibashi got
his doctorate in seismology from the University of Tokyo 12
years later, there were 24 reactors running or under construction, including
six at Tokyo Electric Power Co.’s Fukushima
Dai-Ichi power station.
Seismologists at the time still focused on written records, rather than
geological history, for clues about where and when quakes struck. And it wasn’t
until 1977 that mainstream scientists had the tools to measure the size of
quakes like the magnitude-9 that triggered the Fukushima disaster.
The Richter scale used before then went only to 8.5, or about 6 times
less energy than the March 11 quake.
Significant Damage
“So all of a sudden everyone knew that, hey, there are magnitude-9
earthquakes in the world,” said Robert Geller, a professor of geophysics at the University of Tokyo . “They didn’t know that when they
built the nuclear power
plants at Fukushima
or other plants from that era. But when that became known they should have done
some rethinking.”
Minutes of a June 2009 trade ministry meeting on safety at the Fukushima Dai-Ichi plant show Tokyo Electric and the regulator ignored
scientific findings that emerged after the power station was built.
“We didn’t think the damage would be that significant,” said Isao
Nishimura, a manager at the utility’s nuclear earthquake resistance technology
center, when asked at the meeting why its safety review omitted studies showing
the area had a history of major earthquakes and tsunami.
Debate was cut short by an official from the Nuclear
and Industrial Safety Agency, according to minutes of the meeting obtained
by Bloomberg News. The regulator approved Fukushima
Dai-Ichi’s safety report a month later, despite studies by Tohoku University
geologist Koji Minoura in the 1990s that showed giant tsunami had hit Japan ’s
northeast coast three times in the last 3,000 years.
Russian Roulette
“That’s about one every 1,000 years on average,” said Geller. “If
you’ve got a plant that runs 50 years, you have a 5 percent chance. You’re
talking about Russian roulette.”
Disregard for the science extended to a government panel started in
2001 to revise seismic engineering standards for Japan ’s nuclear plants, said
Ishibashi. He quit the panel after five years of debate that he called rigged
and unscientific.
The revised seismic standards didn’t reflect evidence that earthquakes
could occur in areas where there were no signs of active faults. The omission
allowed the utilities to carry on without undertaking expensive retrofits,
Ishibashi says.
“The point I was trying to make was that if you’re going to have
nuclear plants here in Japan, they should be built to withstand the most severe
shaking that’s been observed,” he said, recalling the date he resigned from the
panel in exasperation on Aug. 28, 2006. “They tried to chip away at that as
much as they could,” he said.
Worst Case Scenario
Masanori Hamada, a Waseda University engineering
professor who also served on the panel, said there were reasons for not
adopting Ishibashi’s views.
“I understood what Ishibashi was saying, but if we engineered factoring
in every possible worst case scenario, nothing would get built,” Hamada said.
“What engineers look for is consensus from the seismologists and we don’t get
that.”
The Fukushima disaster is forcing a rethink
in the U.S.
nuclear industry. A task
force for theNuclear
Regulatory Commission on the disaster recommended in
July that U.S.
utilities re-evaluate earthquake hazards every 10 years.
“At this point there is no requirement to re-review basic seismic
design information,” NRC spokesman Scott Burnell said by e-mail.
In June, Japan ’s
Nuclear Safety Commission instructed its experts to review guidelines for
earthquake and tsunami defenses at nuclear plants.
License to Operate
There are no plans to introduce regular seismic reviews as the U.S. proposes,
said a commission official, who was not authorized to speak to the media and
declined to be identified.
“The nuclear industry has tended to give you a license and then once
you have that license you are deemed safe,” said Norm Abrahamson, a seismologist at the University of
California at Berkeley and an adviser at Pacific Gas & Electric Co.,
the state’s biggest utility.
“Nuclear plants are such huge investments that operators need some
assurance of getting their money back,” Abrahamson said. “They’re looking for
what they would call regulatory stability, but regulatory stability and
scientific change don’t go hand in hand.”
Ishibashi says he didn’t start out as a critic of Japan ’s nuclear industry. In 1976,
when the then 31-year-old researcher at Tokyo
University made his first important
discovery -- that a fault line west of Tokyo was
much bigger than assumed -- the risk to Chubu Electric Power Co.’s Hamaoka
nuclear plant in Shizuoka
prefecture didn’t occur to him. The plant had opened that year above the fault.
His view changed after a magnitude-6.9 quake killed more than 5,500
people on Jan. 17, 1995, and toppled sections of elevated expressway.
\
After a disaster that Japanese engineers had said couldn’t happen, the
nuclear regulator didn’t immediately re-evaluate its construction standards. It
said the plants were “safe from the ground up,” as the title of a 1995 Science
Ministry pamphlet put it. Ishibashi decided to investigate.
The result was an article on Hamaoka published in the October 1997
issue of Japan’s Science Journal that reads like a post-mortem of the Fukushima
disaster: A major quake could knock out external power to the plant’s reactors
and unleash a tsunami that could overrun its 6-meter defenses, swamping backup
diesel generators and leading to loss of cooling and meltdowns.
When the local prefecture questioned industry experts about Ishibashi’s
paper, the response was that he didn’t need to be taken seriously.
Ishibashi a ‘Nobody’
“In the field of nuclear engineering, Mr. Ishibashi is a nobody,”
Madarame said in a 1997 letter to the Shizuoka
Legislature. Madarame, then a professor at the University of Tokyo school of
engineering, is now in charge of nuclear safety in the country.
Requests made to Madarame’s office in October for an interview on his
current views of Ishibashi’s work were declined.
On Oct. 24, Madarame was asked after a regular press briefing for the
commission if he’d changed his opinion about Ishibashi.
“Because of the accident there’s a need to take another look at things,
including the earthquake engineering guidelines, and we’re doing that,” he
said. “Ishibashi contributed a lot to the revisions to the earthquake guidelines
and his comments there are important.” He declined to comment further.
Hamaoka’s reactors, the subject of Ishibashi’s 1997 report, were shut
in May after then-Prime Minister Naoto Kan went on television
to publicly plead with Chubu Electric to close the plant. The utility estimates
it will cost 100 billion yen and 18 months to build a seawall around the
reactors.
Speaking Engagements
Now Professor Emeritus at Kobe
University , Ishibashi
said he hasn’t much time for hiking or other hobbies as his schedule is packed
with speaking engagements.
The message he gives to business leaders and politicians is the focus
on tsunami risk after Fukushima
has deflected attention from the fundamental issue: The danger of having more
than 50 nuclear reactors in one of the world’s most earthquake- prone
countries.
At a private meeting with the Kobe Chamber of Commerce at a Chinese restaurant
on July 31, Ishibashi planned to talk through a slide presentation on the risk
associated with the 13 nuclear reactors on Wakasa Bay
up the coast, nine of which are more than 30 years old.
The reactors, which keep factories running for companies
including Panasonic Corp. (6752)and Kawasaki
Heavy Industries Ltd. (7012) as well as powering the cities of Osaka , Kyoto and Kobe , are in an area that
has had at least five magnitude-7 and magnitude-8 quakes over the last 500
years.
Ishibashi said he got through only a few of his 36 Power Point slides
before his time was up and dinner started. He was seated at a round table next
to the chairman of one of Japan ’s
biggest companies, who Ishibashi asked not be identified because the meeting
was private.
“‘I know you want the reactors shut,’” he said the chairman told him.
“‘But it can’t happen. We need the electricity.’”
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