Los Angeles Times
August 12, 2004
Japan Nuclear Firm Ignored Warnings
Power company admits that it didn't act on
safety reports. Survivors recount how steam and
scalding water leaked, killing four workers.
By Bruce Wallace
Times Staff Writer
August 12, 2004
TOKYO — Admissions of ignored safety warnings
and terrifying accounts of the burst of
superheated steam that killed four people at the
Mihama plant have put Japan's nuclear power
industry on the defensive.
The steam that erupted from a corroded pipe
Monday was not radioactive — just
hot enough, at about
300 degrees Fahrenheit, to kill. But
Kansai Electric Power Co.'s seemingly
casual approach to
maintenance at its facility 200 miles
west of Tokyo has alarmed the public in a
country already skittish about its dependence on
The company admits that
it did not act on safety warnings from
Workers who survived the accident said the
difference between life and death was whether
they had been sitting on chairs, assembling
equipment or were on their feet and able to rush
for the door.
The four men who died
had been sitting and were unable to escape the
high-pressure steam and boiling water pouring
from the sheared pipe above them.
Those who were standing escaped.
"It happened in an instant: The steam burst in
and everything turned white," said one of the
hospitalized survivors, who was quoted in
Japan's Mainichi Daily News. "The floor was
covered by hot water."
The effect was lethal.
Masao Takatori said his 29-year-old nephew,
Hiroya Takatori, "was frothing at the mouth — I
couldn't bear to look at the body." The family
had sat with Hiroya's body all night, he told
The workers were in a secondary facility next to
Mihama's No. 3 reactor, preparing the site for
an inspection the company had scheduled for
Saturday. They did not anticipate danger, and
the only protective
gear they wore were hard hats.
The building was considered so safe that the
power company offered
public tours, occasionally even taking groups of
Company executives acknowledge that they had
been warned by maintenance subcontractors in
April 2003 and again in November that pipes
carrying high-pressure water and steam from the
main reactor to another set of turbines needed
to be replaced.
The pipe that burst had not been checked for
corrosion since it was installed when the plant
opened 28 years ago. Wear from the constant
high-pressure steam reduced the pipe's thickness
over the years from its original 0.4 inch to
one-tenth its original size, far below the
minimum safety requirement — making it visibly
thin, "even to a layman," Industry Minister
Shoichi Nakagawa said after he toured the scene.
Executives told reporters Wednesday that they
had believed they could postpone safety checks
on the pipes until this month.
"We had never expected such rapid corrosion,"
said Akira Kokado, Mihama's deputy plant
Japan's nuclear watchdog agency has given four
companies that use similar designs a week to
ensure its pipes are safe, a survey that will
affect nearly half of the nation's 52 nuclear
plants. Police are also investigating whether
there are grounds to bring charges of
Both the nuclear industry and its advocates in
Japan's government have struggled to find the
right calibration in tone between promises to
get tough on safety violations and attempts to
restore public confidence. In recent years, the
industry has been beset by scandals, including
cases of utilities covering up safety violations
and reactor defects.
Yet in a country almost barren of oil and coal,
nuclear power fills about one-third of the
energy demand. Japan, already the world's
third-largest commercial nuclear power after the
United States and France, plans to build 11
plants within a decade.
That goal seemed farther off Wednesday, as
people absorbed images of power company
President Yosaku Fuji bowing in apology to
distraught family members of the victims. They
made it clear, as Fuji himself said, that
the tragedy "was not
something that could be laid to rest by an
Images of nuclear power executives prostrating
may only stiffen public opinion against building
new nuclear plants. But even critics accept that
blocking new reactors
means Japan will have to rely more on its aging
"It's a vicious cycle," said Hideyuki Ban of the
Citizens' Nuclear Information Center, a leading
critic of nuclear power.
Blind spots of inspection
The nuclear plant accident that occurred
Monday in Mihama, Fukui Prefecture, is a
shocking reminder that the
nation's nuclear safety inspection system is
flawed. Four maintenance workers in a
building housing steam turbines were killed and
seven others were injured, some critically, when
high-temperature steam blew off from a ruptured
condenser pipe. In terms of the number of
deaths, it was the worst accident in the history
of the nation's nuclear power program.
This is the second time in Japan that a
nuclear accident has claimed the lives of
workers. In 1999, two men died of radiation
exposure at a nuclear-fuel reprocessing facility
in Tokaimura, Ibaraki Prefecture. At the time,
residents in the vicinity were ordered to
evacuate to avoid possible exposure to
Fortunately, no radiation leaks occurred this
time because the pipe that ruptured is not
directly connected to the reactor.
The cause of the damage
has yet to be determined. A thorough
investigation is required, all the more because
similar accidents could occur in other
light-water nuclear plants or in thermal power
plants that likewise generate electricity by
According to the Kansai Electric Power Co.
(KEPCO), the pipe in question -- which carries
high-pressure, high-temperature water from the
turbine to the steam generator -- is about 56
centimeters in diameter and is made of carbon
steel with a designed thickness of about 10
millimeters. Company officials say the workers
were exposed to superhot steam released from a
broken section of the pipe.
An inspection by the Nuclear and Industrial
Safety Agency, an affiliate of the Ministry of
Economy, Trade and Industry, reveals that the
steel of the damaged part has thinned to
approximately 1.4 millimeters.
The agency believes this
may have been caused by the gradual abrasion of
the steel due to high-pressure, high-temperature
water flows, as well as by certain weaknesses in
the structure and quality of the piping.
Even more disturbing is the fact that the
condenser pipe had never
been inspected since the reactor went
into operation in December 1976. In 1986, it
should be noted, a similar steam-pipe accident
occurred at a nuclear plant at Surry, in the
U.S. state of Virginia, killing four workers.
The problem seems to be that
equipment in the
steam-generating secondary system, unlike those
in the primary loop that recycles water through
the reactor core, is not subject to regular
inspection under existing laws. In other
words, secondary-loop equipment is left to
voluntary inspection by individual operators.
According to KEPCO, secondary equipment such
as condenser piping is visually inspected every
day. As for detailed items that do not permit
such cursory inspection, such as pipe thickness,
one-fourth are checked
every 10 years. So it takes 40 years to complete
a full round of inspections.
On Tuesday, the company acknowledged that it
should have conducted a detailed inspection of
the pipe much earlier, saying it was informed of
a potential problem by a maintenance contractor
last November. Police are reportedly looking for
evidence of professional negligence resulting in
death and injury.
KEPCO, the nation's second-largest power
supplier, has had a nuclear accident before. In
February 1991, a broken steam-generator tube at
the No. 2 reactor in Mihama -- Monday's tragedy
occurred at No. 3 -- caused massive leaks of
radioactive water from the primary coolant
Monday's accident proves yet again that
Japan's aging nuclear
plants face a host of technical problems.
Of the 52 commercial reactors now in operation,
20 went on stream in the 1970s. In the case of
pressurized-water reactors -- the same type as
those at the Mihama plant -- it has been
revealed that stress corrosion cracks have
developed in steam generators and
reactor-container covers. As for boiling-water
reactors, similar cracks have been found in
reactor shrouds and recycling pipes.
Power companies, as well as the government,
are at pains to extend reactor service life to
60 years from the original 30 to 40 years.
What's more, under the so-called "pluthermal
(plutonium thermal) project," these plants are
expected to start burning plutonium recovered
from spent nuclear fuel.
It would be wrong to make light of the latest
incident just because it did not cause radiation
leaks. With or without radiation exposure,
safety remains a blind
spot of sorts in Japan's nuclear power industry.
What is needed is a fundamental review of the
inspection system, including the rule that
doesn't require a full-dress plant inspection
until after 30 years of operation.
The Japan Times: Aug. 12, 2004
Kepco failed to inspect
aging reactor pipe despite warning
Check was urged long before fatal steam
TSURUGA, Fukui Pref. (Kyodo) Kansai Electric
Power Co. admitted Tuesday it failed to check a
reactor pipe in its Mihama nuclear plant in
Fukui Prefecture that burst and scalded four
workers to death with steam, even though it knew
for months that it needed inspection.
The steam leak from the carbon steel pipe at
Mihama's No. 3 reactor Monday afternoon also
injured seven other workers. The pipe had not
been changed in 27 years of operation.
It was Japan's worst nuclear plant accident
in terms of the death toll, but there was no
Fukui Prefectural Police are looking for
evidence that the nation's second-largest
utility committed professional negligence
resulting in death and injury, investigative
Kepco said after the accident that it found a
hole in the 56-cm-diameter pipe that
sends pressurized steam in the turbine facility.
It said steam
erupted from the ceiling of the second floor,
onto the 11 victims.
According to the sources, the section of pipe
that was damaged should have been part of an
earlier inspection but was excluded due to a
The utility was notified of the mistake by
Nihon Arm Co., a subcontractor that services its
power plants, in November, but did nothing about
it, the sources said.
The sources said that although
Nihon Arm noticed the
omission in April, it did not immediately tell
Kepco. Nihon Arm meanwhile says its staff
informed Kepco in April.
Investigators said the thickness of the burst
pipe is normally 10 mm, but it had been worn
down to 1.4 mm in some places, most likely due
to the swirling of the coolant water inside.
required to change the pipes before their
thickness erodes to 4.7 mm. But Kepco
had not conducted any ultrasound inspections to
check pipe thickness since the No. 3 reactor
began operations in December 1976.
After visiting the site, Shoichi Nakagawa,
minister of economy, trade and industry, told a
news conference: "To put it flatly, (the damaged
pipe) was extremely thin. It looked terrible,
even to a layman."
Nakagawa, who is in charge of administrative
measures to ensure the safety of nuclear power,
also apologized to local residents.
Kepco inspected other facilities and replaced
the pipes at the Takahama Nuclear Power Plant's
No. 3 reactor and Oi Nuclear Power Plant's No. 1
reactor, both in Fukui Prefecture, with
stainless steel ones between 1998 and 2003
because they had worn so thin that they would
not last another two years, the sources said.
Kepco said Tuesday that it will shut down its
other nuclear reactors for inspection if there
are any major items that had not been checked.
Police also suspect
that Kepco violated safety regulations
stipulating the complete shutdown of reactors
for annual checks when it had more than 200
workers move in inspection equipment while the
reactor was still running, the sources said.
They suspect the
utility tried to cut costs by keeping the
reactor in operation until the last possible
minute before the inspection, which
was to start Friday.
Kepco officials said large numbers of workers
are often inside reactor facilities during
preparations for annual inspections but claimed
there is no legal problem with the practice.
If it is proved that negligence took place,
the accident will further heighten public
distrust in the country's nuclear power
industry, which has been rocked by accidents and
scandals, including utilities covering up safety
violations and reactor defects.
The Nuclear and Industrial Safety Agency on
Tuesday instructed four utilities that operate
similar pressurized-water reactors to check
Kepco President Yosaku Fuji visited hospitals
Tuesday where the injured were being treated and
met with relatives of the deceased.
Although he apologized to the families for
the accident, Fuji said they told him the fiasco
was "not something that can be laid to rest by
Masao Takatori, uncle of 29-year-old Hiroya
Takatori, one of the four killed, said he felt
anger and bitterness over his nephew's death.
"He was frothing at the mouth -- I couldn't
bear to look at the body," he said, adding that
the victim's parents stayed with the body
throughout the night.
Kazuo Nakagawa, a cousin of 41-year-old
Kazutoshi Nakagawa, who also died, noted that
there are many in his neighborhood who work in
the nuclear power industry.
Kazutoshi "often said his job wasn't
dangerous," he said. "We've lost a good family
Accident de Mihama : le
Japon ordonne la vérification de toutes ses
L'accident est le plus meurtrier de l'histoire
nucléaire du Japon. Intervenant après une longue
série d'incidents moins graves, il a relancé les
doutes sur les mesures de sécurité prises dans
les centrales nippones.
Tokyo a ordonné mardi 10 août la vérification
de toutes les centrales nucléaires de l'archipel
après l'aveu, par l'opérateur de l'installation
de Mihama (Centre), d'une absence de contrôles
efficaces depuis vingt-huit ans sur un conduit
de vapeur non radioactive dont la rupture a fait
quatre morts lundi.
Le gouvernement japonais, via l'Agence pour
la sécurité nucléaire et industrielle (NISA,
publique), a exigé de la dizaine de sociétés
privées qui gèrent les 52 centrales du pays de
passer au crible l'ensemble des installations.
Cet ordre a été lancé après que Kansai Electric
Power Company (Kepco), société privée cotée en
Bourse qui gère la centrale de Mihama, eut admis
que la canalisation qui a explosé lundi vers 15
h 30 (8 h 30 à Paris) ne correspondait plus du
tout aux normes de sécurité. La paroi du conduit
ne faisait plus que 1,4 mm, nettement en dessous
des 4,7 mm requis, a reconnu un porte-parole de
Kepco, Haruo Nakano.
"Nous avons effectué des inspections
visuelles mais jamais par ultrason" depuis
1976, a-t-il admis. Les tests ultrason ne sont
pas obligatoires même s'ils sont les seuls à
pouvoir déceler une corrosion interne. La vapeur
échappée de la canalisation n'était pas
radioactive mais atteignait une température de
plus de 140 degrés, selon Kepco.
"Nous sommes responsables", a ajouté
le directeur du contrôle de la qualité, Koji
Ebisuzaki, lors d'un point presse tenu à Mihama,
à 350 kilomètres à l'ouest de Tokyo.
Sept employés restaient hospitalisés mardi
dans la préfecture de Fukui, où se trouve
Mihama. Deux étaient dans un état critique, dont
un homme brûlé sur 80 % du corps et ne respirant
qu'à l'aide d'un appareil, ont précisé les
ACCIDENT LE PLUS MEURTRIER
L'accident est le plus meurtrier de
l'histoire nucléaire du Japon. Intervenant après
une longue série d'incidents moins graves, il a
relancé les doutes sur les mesures de sécurité
prises dans les centrales nippones.
"Etaient-elles au point à la centrale de
Mihama ?", se demande le quotidien
Yomiuri Shimbun (conservateur). La presse
fait ainsi ses manchettes avec le chiffre "1,4"
(millimètre) en référence à l'épaisseur de la
paroi de la canalisation qui a explosé.
La NISA, qui a lancé sa propre enquête en
plus de celle de la police, se focalisera sur ce
problème, a indiqué Michio Yamaguchi, un
responsable de l'Agence. "Nous n'avons pas
encore tiré nos conclusions mais c'est une des
possibilités", a-t-il dit.
Quant à l'enquête policière, un porte-parole
de la police locale a refusé de confirmer des
informations de presse selon lesquelles une
inculpation formelle pour incurie était en
préparation contre Kepco.
Le vice-président de la centrale de Mihama,
Akira Kokado, a admis que l'accident allait
miner la confiance dans une source d'énergie
d'un peuple ayant subi des bombardements
L'accident de Mihama a coïncidé avec le 59e
anniversaire du largage de la seconde bombe
atomique sur Nagasaki, le 9 août 1945. "Nous
espérons restaurer la confiance en enquêtant sur
la cause de l'accident et en réexaminant les
procédures d'inspection", a déclaré le
L'association Greenpeace a appelé le Japon à
"fermer son industrie nucléaire",
prédisant d'autres accidents.
"Le résultat de l'enquête pourrait
déterminer le cours de la politique nucléaire
japonaise à l'avenir", assure le quotidien
Mainichi Shimbun (libéral). Le Japon est le
troisième producteur mondial d'énergie
nucléaire, après les Etats-Unis et la France,
selon l'Agence pour l'énergie nucléaire (AEN),
basée à Paris.
L'accident ne compromet cependant pas la
candidature japonaise pour le projet
international de réacteur de fusion Iter,
également voulu par la France, assure un
responsable du Bureau de la fusion nucléaire au
ministère des sciences. "Il n'y a strictement
aucun rapport", a déclaré Takashio Hayashi.
New York Times
August 11, 2004
Rust and Neglect Cited at Japan Atom
By JAMES BROOKE
TOKYO, Wednesday, Aug. 11 - A section
of steam pipe that blew out Monday,
killing four workers at a Japanese
nuclear power plant, had not been
inspected in 28 years and had corroded
from nearly half an inch to a thickness
little greater than metal foil,
authorities said Tuesday.
"To put it bluntly, it was extremely
thin," Shoichi Nakagawa, Japan's
minister of the economy, trade and
industry, said Tuesday after touring the
power plant, in Mihama, about 200 miles
west of here. "It looked terrible, even
in the layman's view."
Although the carbon steel pipe
300-degree steam at high pressure, it
had not been inspected since the power
plant opened in 1976. In
April 2003, Nihon Arm, a maintenance
subcontractor, informed the Kansai
Electric Power Company, the plant owner,
that there could be a problem. Last
November the power company scheduled an
ultrasound inspection for Aug. 14.
"We thought we could postpone the
checks until this month," Akira Kokado,
the deputy plant manager, told reporters
at Mihama. "We had never expected such
But on Monday, four days before the
scheduled shutdown for the inspection,
superheated steam blew a two-foot-wide
hole in the pipe, scalding four workmen
to death and injuring five others
seriously. The steam that escaped was
not in contact with the nuclear reactor,
and no nuclear contamination has been
Initial measurements showed that the
steam had corroded the affected section
of pipe from its original thickness of
0.4 inches to 0.06 inches, less than
one-third the minimum safety standard.
Kansai Electric said in a statement that
the pipe "showed large-scale corrosion."
"We conducted visual inspections but
never made ultrasonic tests, which can
measure the thickness of a steel pipe,"
said Haruo Nakano, a Kansai Electric
In response, Japan's nuclear and
industrial safety agency ordered
ultrasound inspections at four other
power companies that own nuclear plants
with the same type of pressurized water
reactors. The inspections will involve
nearly half of Japan's 52 nuclear power
The Kyodo news agency reported
Wednesday that corrosion problems had
prompted operators in recent years to
replace the steam pipes at 16 plants of
a design similar to that of the plant at
With television news helicopters
swarming over the Mihama plant on
Monday, government officials were quick
to promise that a full investigation
would take place.
"We must put all our effort into
determining the cause of the accident
and to ensuring safety," Prime Minister
Junichiro Koizumi said Tuesday. He added
that the government would respond
"resolutely, after confirming the
the police opened an investigation to
determine why 221 workers were in the
reactor facility at the time of the
accident. The subcontractor
has said they were moving in equipment
and testing materials in preparation for
a shutdown on Friday and subsequent
Kyodo reported that
believed that the company might have
neglected safety standards by allowing
workers to prepare for an annual
inspection while the plant was still
running. But government leaders also
tried to bolster flagging public support
for nuclear power.
"Nuclear power has a significant
impact in our lives," Mr. Koizumi said
Tuesday. "We have to pay close attention
so that our lives won't be affected by
planned to build an additional 11
reactors in this decade,
increasing the nation's reliance on
domestic nuclear power to 40 percent of
its electricity needs. Already slowed by
local opposition, that program may now
be stalled by the accident, the most
deadly in the history of nuclear power
it's virtually impossible to build new
nuclear facilities now,"
a liberal newspaper, said
in an editorial on Tuesday. "But
facilities are wearing out, and there
are worries about increasing problems
with corroding pipes, rupturing valves
and the reactor core."
Keizai Shimbun, a business daily,
worried that the accident could
undermine public support in Japan for
"We must find the cause of the
accident and urgently come up with
measures to prevent such an accident
from happening again," the newspaper
editorialized. "This accident seriously
damaged public confidence in nuclear
Shimbun, a conservative newspaper,
warned, "Care must be taken not to
overemphasize the dangers involved in
the operation of nuclear power stations,
which could lead to an overreaction."
Japan has the world's third-largest
nuclear power industry, after the United
States and France.
Shimbun, a liberal newspaper,
said further expansion of nuclear power
in Japan was now in play. It said in an
editorial, "As we investigate the cause
of the accident, the outcome could
determine the course of Japan's nuclear
Accident at Nuclear Plant In
Japan Kills Four Workers
No Indication of a Radiation Leak, Officials Say
By Anthony Faiola
Washington Post Foreign Service
Tuesday, August 10, 2004; Page A15
TOKYO, Aug. 9 -- Four people were killed and
seven injured Monday by sprays of superheated
steam at a nuclear power plant 200 miles west of
Tokyo, but officials familiar with the accident
said there was no indication of a radiation
A spokesman for the plant, which is located
in the picturesque village of Mihama and run by
Kansai Electric Power, told reporters that the
accident occurred when steam spewed from a leak
in a turbine building at one of the plant's
reactors, with bursts of the steam reportedly
reaching temperatures as high as 300 degrees
Fahrenheit. The accident automatically shut the
The incident follows a number of
mishaps and other problems that have plagued
Japanese nuclear power plants in recent years,
raising concerns over the safety of the
country's 52 nuclear power complexes.
Japan, the world's second-largest economy,
relies on nuclear power for 30 percent of its
The Japanese government launched an
investigation as Prime Minister Junichiro
Koizumi told reporters that "we must put all our
effort into determining the cause of the
accident and to ensuring safety." He added the
government would respond "resolutely, after
confirming the facts."
According to the Kyodo news service, the dead
and injured reportedly were subcontractors
preparing for a regular inspection. They were
laboring under a 22-inch-wide pipe when it
The leak was caused by a
lack of cooling water in
the reactor's turbine and by metal erosion in a
condenser pipe, according to Kansai
The company told reporters that the broken
pipe, originally 10
millimeters thick, had eroded to a thickness of
only 1.4 millimeters. The pipe had not been
replaced since it was first installed 27 years
"I'm sorry to have caused such trouble,"
Yosaku Fuji, Kansai Electric's president, said
at a news conference. "I cannot find the words
to say to the deceased and the bereaved family
In February 1991, a tube inside a steam
generator at another one of the plant's reactors
broke, causing 55 tons of radioactive water to
leak from the main cooling system into the
secondary system that powers the reactor's
During that accident, an emergency
core-cooling system was activated in Japan for
the first time.
The Mihama plant, located near popular beach
resorts, was the first nuclear plant built by
Kansai Electric. Its first reactor began service
in November 1970.
The Japanese public has grown increasingly
alarmed by flaws and failures at nuclear plants
here. In 1999, a radiation leak caused by human
error at a fuel-reprocessing plant in Tokaimura,
northeast of Tokyo, killed two workers and
forced the evacuation of thousands of nearby
A string of safety problems and attempted
coverups followed. In February, eight workers
were exposed to low-level radiation at a power
plant when they were accidentally sprayed with
contaminated water, although the contamination
levels were not considered dangerous.
[The Reuters news agency reported two other
incidents at nuclear power plants in Japan on
Monday. In one, Tokyo Electric Power -- Japan's
biggest electricity producer -- said it had shut
a nuclear power generation unit at its
Fukushima-Daini plant because of a water leak.
In the other, a garbage disposal site at a
nuclear power plant in Shimane prefecture in
western Japan caught fire, Chugoku Electric
Power Co. said. The blaze was quickly
Special correspondent Sachiko Sakimaki
contributed to this report.
New York Times
August 10, 2004
Four Workers Killed in
Nuclear Plant Accident in Japan
By JAMES BROOKE
TOKYO, Aug. 9 - Superheated steam erupted
from the ceiling of a nuclear power plant north
of Kyoto on Monday, killing four workers and
severely burning five others. It was Japan's
worst nuclear accident.
Officials said the steam was not contaminated
by radioactivity. No evacuations were ordered of
the town of Mihama, where the plant is situated.
The Sea of Japan port is about 40 miles north of
Kyoto, the country's historic capital.
"Radioactive materials weren't contained in
the steam that leaked out," an official for the
Nuclear and Industrial Safety Agency said at a
news conference here.
The Kansai Electric Power Company, owner of
the 28-year-old reactor at Mihama, said in a
statement, "This incident will have no radiation
effect on the surrounding environment."
But the accident is likely to add to Japanese
concerns about nuclear power, just as high oil
prices and the war in Iraq make it more
attractive to economic planners here. With the
world's third largest nuclear power industry,
after the United States and France, Japan relies
on 52 nuclear power plants to generate almost
one-third of the nation's electricity. But it
has also been heavily dependent on oil imports
from the Middle East and has worked aggressively
with Russia over the last year to develop oil
and gas deposits in Siberia.
A government plan calls for building 11 more
nuclear plants and raising the percentage of the
nation's power supplied by nuclear energy to
nearly 40 percent by 2010. But these plans have
stalled as the public has become increasingly
wary of nuclear power. Many towns have held
referendums, voting against building nuclear
Wariness has been fueled by accidents and by
a cover-up culture in which employees show far
greater loyalty to their companies than to the
public's right to know.
Last summer, the Tokyo Electric Power
Company, the nation's largest utility, was
forced to close all 17 of its nuclear plants
temporarily after admitting that it had faked
safety reports for more than a decade.
"After the Tepco scandal of two years ago,
today's accident would accelerate people's worry
and suspicion about the safety management of the
nuclear power plants," Satoshi Fujino, a staff
member at Citizens' Nuclear Information Center,
a private nuclear power watch organization, said
in an interview. "This plant is pretty old, and
there are many plants even older."
While the accident on Monday appeared not to
involve radioactive releases, the horrific
nature of the deaths has augmented the
"Staff rushed in screaming," a 65-year-old
company cafeteria worker told Kyodo News. "I put
in a container all the ice I could find and gave
Company officials said the accident took
place in the turbine building of the No. 3
nuclear reactor in Mihama, which was scheduled
to be closed Saturday for routine maintenance.
About 200 workers were in the building at
3:30 p.m., when a two-foot-wide hole burst in a
steel pipe that carried steam, pressurized and
heated to as much as 400 degrees.
All of the dead and injured men had been
working in the second-floor room where the pipe
"The ones who died had stark white faces,"
Yoshihiro Sugiura, a doctor who treated them,
told The Associated Press. "This shows they had
rapidly been exposed to heat."
The United States had a similar accident at
the Surry nuclear power plant in southern
Virginia almost two decades ago, when an 18-inch
steel pipe burst and released 30,000 gallons of
boiling water and steam, killing four people.
Japanese nuclear safety officials said it
would be impossible for the leaked steam to
contain radioactivity because the water in the
steam turbines does not come in contact with
water used as a coolant for the reactor.
Kansai Electric said it closed the
826,000-kilowatt nuclear generation unit at the
reactor and was not sure when it would be
A Kansai Electric official said at the news
conference that the company was trying to
determine the cause of the accident, and that
the other two reactors at the complex would
Yosaku Fuji, president of Kansai Electric,
apologized and bowed deeply before reporters at
the televised news conference.
"We are deeply sorry to have caused so much
concern," he said. "There is nothing we can say
to the four who lost their lives. We pray for
their souls from the bottom of our hearts and
offer our condolences to their families. We are
With the accident occurring on the 59th
anniversary of the nuclear bombing of Nagasaki,
political and industry leaders were quick on
Monday to assure the public that a thorough
investigation would take place.
"I think we must do our best to investigate
the cause, to prevent a repeat, and to implement
safety measures," said Prime Minister Junichiro
Takuya Ito, the public relations director of
the Federation of Electric Power Companies,
expressed concern in an interview that the
accident could further hurt popular trust in
nuclear power "because these are the first
deaths from an accident in a nuclear power plant
in operation." The most recent fatality in the
nuclear power industry was in 1999, at a
fuel-reprocessing plant in Tokaimura, northeast
of Tokyo, when a radiation leak killed two
workers, exposed 600 people to low levels of
radiation, and caused the evacuation of
thousands of residents. That accident was caused
by three workers who tried to save time by
mixing excessive amounts of uranium in buckets
instead of using special mechanized tanks. Two
of the workers who caused the disaster later
died from their injuries.
More recently, in February, eight workers
were exposed to low-level radiation at another
power plant when they were accidentally sprayed
with contaminated water. The doses were not
On Monday, a small fire broke out at a
nuclear facility in Shimane Prefecture, 375
miles southwest of Tokyo. No one was injured and
it posed no threat of radiation leaks.
"A fire broke out at a waste processing site,
where we also have a laundry facility. But it
was quickly extinguished," said a spokesman for
Chugoku Electric Power Company, which operates
New York Times
August 10, 2004
Japan Plant Operator Knew
Cooling Pipe Was a Safety Threat
By THE ASSOCIATED PRESS
MIHAMA, Japan -- The
faulty cooling pipe at the
center of Japan's deadliest nuclear power plant
accident had not been inspected since 1996,
despite a warning last year that it was a safety
threat, the plant operator said
The dangerously corroded pipe -- which
carried boiling water and superheated steam --
burst at the Mihama reactor on Monday, burning
to death at least four workers and injuring
seven others, two of them seriously. No
radiation was released, officials said.
The announcement came as dozens of police
agents and nuclear energy officials arrived
Tuesday at the plant in Mihama, about 200 miles
west of Tokyo, to investigate operator Kansai
Electric Power on suspicion of negligence
resulting in death.
The accident and suspected lapses deepened
concerns about the safety of Japan's 52 nuclear
plants, which supply about a third of the
country's electricity. Two workers died in a
radioactive leak at a plant northeast of Tokyo
It was unclear how the accident would affect
the operation of Japan's other nuclear plants.
The country's nuclear agency was considering a
call for all plants to inspect their cooling
pipes, a spokesman said.
Kansai Electric deputy plant manager Akira
Kokado said private contractors conducting
inspections for the company notified management
in April 2003 that the cooling pipe was overdue
for a thorough safety check.
Sections of the pipe were last checked in
1996 and deemed safe at that time, said Koji
Ebisuzaki, Kansai Electric's chief manager for
quality control. Last November, the plant
scheduled an ultrasound inspection of the pipe
for Aug. 14 -- next Saturday.
``We thought we could delay the checks until
this month,'' Kokado told a news conference.
``We had never expected such rapid corrosion.''
The national government in Tokyo -- which
plans to build another 11 nuclear power plants
by 2010 -- called for an open probe of the
accident as investigators headed to the site.
``Prime Minister (Junichiro) Koizumi told me
it is important that nothing be hidden from the
nation,'' said Economy, Trade and Industry
Minister Shoichi Nakagawa.
Officials, however, balanced the call for an
aboveboard probe with warnings that the accident
should not further dim the reputation of nuclear
power in Japan.
``Nuclear power has a significant impact in
our lives,'' Koizumi told reporters Tuesday.
``We have to pay close attention so that our
lives won't be affected by this accident.''
Kyodo News service reported that the
country's Nuclear and Industrial Safety Agency
had ordered four power companies to check
nuclear plant cooling systems for corrosion. The
report, citing unidentified officials, said
plants failing the tests would be temporarily
Agency spokesman Sachiko Muranaka, however,
denied that such an order had been issued,
adding that the agency's actions would depend on
the outcome of the Mihama investigation.
Monday's leak was caused by a lack of cooling
water in the reactor's turbine. After the
accident, Kansai Electric officials found a hole
in a condenser pipe. The water flowing through
the pipe was about 300 Fahrenheit.
The plant's No. 3 nuclear reactor
automatically shut down when steam began spewing
from the leak. Its two other reactors were
Though the burst pipe had originally been 0.4
inch thick, the pipe had eroded to as thin as
.06 inch in the 28 years since the reactor was
built in 1976.
An ultrasound test might have detected the
thinning, but Kansai never carried out such
inspections, Kokado said, adding the company may
have to review the way it conducts checkups.
Kansai revamped its safety guidelines after
the United States suffered a similar accident at
the Surry nuclear power plant in southern
Virginia in 1986. Four people died in that
The Mihama accident followed a string of
accidents, leaks and other safety lapses at
Japanese nuclear power plants, and was clearly
troubling to people in the area.
The Mihama deaths also come as Japan is
bidding to host the world's first large-scale
nuclear fusion plant, the $12 billion
International Thermonuclear Experimental
Reactor. But the project's sponsors -- the
European Union, the United States, Russia,
Japan, South Korea and China -- remain
deadlocked over whether to build the plant in
Japan or France.
In Japan's 1999 accident, a radiation leak at
a fuel-reprocessing plant in Tokaimura,
northeast of Tokyo, killed two workers and
caused the evacuation of thousands of residents.
That accident was caused by two workers who
tried to save time by mixing excessive amounts
of uranium in buckets instead of using special
Several major power-generation companies have
since been hit with alleged safety violations at
their reactors, undermining public faith in
nuclear energy and leaving Japan's nuclear
program in limbo.
August 10, 2004
NATION'S WORST NUCLEAR
Steam leak at Fukui reactor kills four
Four workers were killed and seven others
were injured Monday when steam leaked from a
nuclear reactor in Mihama, Fukui Prefecture, in
Japan's worst nuclear plant accident, rescue
High-temperature steam leaks from the No. 3
reactor at Kansai Electric Power Co.'s Mihama
Nuclear Power Plant in Fukui Prefecture.
According to information received by the Nuclear
and Industrial Safety Agency in Tokyo, the leak
took place at around 3:28 p.m. at a facility
housing the turbines for the No. 3 reactor at
Kansai Electric Power Co.'s Mihama Nuclear Power
Local authorities and Kepco officials said
the deaths and injuries were probably due to
exposure to high-temperature steam. Of the seven
listed as injured, two were in serious
condition, according to the Fukui Prefectural
The 826,000-kilowatt reactor automatically
shut down after the incident, officials at the
nation's second-largest utility said, adding
they believe a lack of cooling water in the
plant led to the accident.
No radiation is believed to have leaked
outside the facility, and sources at the Defense
Facilities Administration Agency said Fukui
Prefecture officials did not see a need for
Self-Defense Forces elements to be dispatched to
the town to assist in disaster relief.
The accident occurred during regular
maintenance in a facility housing the reactor
turbines, according to Kepco. The dead and
injured were all employees of Kiuchi Keisoku, a
Kepco subcontractor based in Tennoji Ward,
Osaka. Kepco said there were about 200 people in
The four dead were identified as Hiroya
Takatori, 29, Kazutoshi Nakagawa, 41, Tomoki
Iseki, 30 and Eiji Taoka, 46.
Kiuchi Keisoku officials said Kepco had asked
for a regular inspection of the turbines and
workers had been moving the necessary equipment
into the facility when the accident occurred.
Kiuchi Keisoku conducts turbine inspections at
the Mihama plant once a year.
A 65-old woman who works in a cafeteria in
the plant said: "Staff rushed (into the
cafeteria), screaming. I put in a container all
the ice I could find and gave it to them.
"I don't know exactly what happened. This is
the first time an incident like this has
happened in my 14 years of work here."
The building is where steam heated to some
200 degrees moves turbines to generate
electricity. The steam is produced from
secondary cooling water and is not radioactive,
Kepco officials said.
The accident apparently occurred when steam
leaked as a result of damage to the turbines or
some other problem, the officials added. Kepco
said it has found a hole in a 50-cm diameter
pipe that feeds steam in the turbine facility.
Kepco President Yosaku Fuji apologized for
the accident at an evening news conference,
saying, "We are deeply sorry for those who have
died and their families, and for causing the
He did not comment on how he would take
responsibility, saying he cannot answer until
the exact cause of the accident is known.
The Nuclear and Industrial Safety Agency said it
would dispatch a six-member expert team to look
into the accident.
Speaking to reporters at the Prime Minister's
Official Residence, Prime Minister Junichiro
Koizumi said it was regrettable the accident led
to many fatalities and injuries."I would like
those concerned to fully grasp the facts and act
The No. 3 reactor where Monday's accident
took place began commercial operations in
In February 1991, a tube inside a steam
generator at the No. 2 reactor in the same plant
broke, resulting in 55 tons of radioactive water
leaking from the main cooling system into the
secondary system that powers the reactor's
That accident was the first time in Japan
that an emergency reactor core cooling system
Until Monday, the nation's worst nuclear
accident occurred Sept. 30, 1999, at a nuclear
plant in Tokaimura, Ibaraki Prefecture. Two
employees who were exposed to extremely high
doses of radiation died, and 663 others were
exposed to lower amounts of radiation.
August 9 2004
Accident kills four at Japan’s nuclear plant
By David Pilling in Tokyo
Japan's worst nuclear-plant accident killed
at least four people and injured seven in Fukui
prefecture on Monday, threatening to further
undermine confidence in the country's nuclear
industry among an already-sceptical public.
Kansai Electric Power (Kepco), which runs the
plant in the city of Mihama about 200 miles west
of Tokyo, said the accident occurred in the
number three reactor after superheated steam
spewed from a turbine, causing severe burns to
workers who were preparing the plant for an
Although no radiation escaped and officials
did not need to evacuate the area around Mihama,
the incident will further damage the nuclear
industry's reputation among the Japanese public.
The world's nuclear
contractors are relying on Japan and other Asian
countries to lead a global revival of demand for
new power stations.
Concerns over the availability and cost of
alternative sources of energy, and doubts as to
whether global climate change can be tackled
without nuclear power, are persuading
governments to consider ordering new nuclear
According to the World Nuclear Association,
Japan has three reactors under construction and
plans to build a further 14.
The Japanese industry has
been trying to mend its reputation after Tokyo
Electric Power was forced to close down all its
17 nuclear plants last year after falsifying
A series of scandals has led to what the
government says is a tightening of regulations
and monitoring procedures. Although Monday's
accident occured in an area not directly linked
to nuclear generation, it is bound to raise
questions about safety controls.
Only hours after Monday's
accident, a fire broke out in a laundry room in
a nuclear plant in Kashima, Shimane prefecture.
Kepco said it was investigating the cause of
the accident, but drew attention to a ruptured
pipe in which water heated to 280°C flows into a
turbine. Mihama was shut down in 2002 after
liquid used to pump coolant into the reactors
leaked. In 1991, radioactive water escaped from
the cooling system at reactor number two, the
first accident of its kind in Japan.
Before Monday, Japan's worst nuclear plant
accident happened in 1999 at Tokaimura
reprocessing facility, Ibaraki prefecture, when
two workers died after mixing uranium in
buckets. In that incident, the government was
criticised for being slow to react, prompting
the establishment of new systems to speed up
responses to accidents.
Junichiro Koizumi, the prime minister, said
on Monday: “The government must do its utmost to
A third of Japan's electricity is generated
by nuclear power, although plans to raise that
have been dropped after the public reaction to
The public in Japan, the only country to
suffer the effects of a nuclear bomb, is
extremely sensitive to nuclear accidents. Monday
was the 59th anniversary of the atomic bombing
Additional reporting by Clive Cookson in
London and Sheila McNulty in Houston