Tin báo chí thế giới về
tai nạn ngày 9 tháng 8 năm 2004
tại Mihama, Nhật Bản
(cập nhật thường xuyên)
 

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 nuclear power.

The company admits that it did not act on safety warnings from subcontractors.

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 reporters.

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 schoolchildren through.

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 manager.

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 professional negligence.

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 apology."

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 ones.

"It's a vicious cycle," said Hideyuki Ban of the Citizens' Nuclear Information Center, a leading critic of nuclear power.

 

Japan Times
12-8-2004

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 radiation.

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 steam turbines.

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 system.

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


Japan Times
11-8-04

Kepco failed to inspect aging reactor pipe despite warning
Check was urged long before fatal steam accident

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 radiation leak.

Fukui Prefectural Police are looking for evidence that the nation's second-largest utility committed professional negligence resulting in death and injury, investigative sources said.

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 Kepco error.

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.

Operators are 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 their facilities.

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 an apology."

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 man."


LE MONDE
10-8-04

Accident de Mihama : le Japon ordonne la vérification de toutes ses centrales nucléaires

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 autorités hospitalières.

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 atomiques.

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 vice-président.

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.

Avec AFP


 
New York Times
August 11, 2004

Rust and Neglect Cited at Japan Atom Plant

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 carried 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 rapid corrosion."

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 reported.

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 spokesman.

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 plants.

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 Mihama.

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 facts."

On Tuesday, 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 inspection.

Kyodo reported that investigators 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 this accident."

Japan 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 in Japan.

"In Japan it's virtually impossible to build new nuclear facilities now," Asahi Shimbun, 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."

Nihon Keizai Shimbun, a business daily, worried that the accident could undermine public support in Japan for nuclear power.

"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 safety."

Yomiuri 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.

Mainichi 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 energy policy."

 


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 leak.

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 facility down.

The incident follows a number of attempted coverups, 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 electricity.

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 apparently burst.

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 Electric.

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 ago.

"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 members."

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 turbine.

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 residents.

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 extinguished.]

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 plants.

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 publicity.

"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 it."

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 burst.

"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 restarted.

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 continue running.

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 truly sorry."

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 Koizumi.

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 considered dangerous.

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 the site.


 

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 Tuesday.

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 in 1999.

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 shut down.

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 operating normally.

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 accident.

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 mechanized tanks.

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.


 

 


Japan Times
August 10, 2004

NATION'S WORST NUCLEAR ACCIDENT
Steam leak at Fukui reactor kills four workers

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 officials said.

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 Plant.

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 Police.

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 facility.

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 accident."

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 accordingly,"he said.

The No. 3 reactor where Monday's accident took place began commercial operations in December 1976.

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 turbines.

That accident was the first time in Japan that an emergency reactor core cooling system was activated. 

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.


FINANCIAL TIMES
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 inspection.

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 power stations.

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 safety data.

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 ensure safety.”

A third of Japan's electricity is generated by nuclear power, although plans to raise that have been dropped after the public reaction to safety scandals.

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 of Nagasaki.

Additional reporting by Clive Cookson in London and Sheila McNulty in Houston


New York Times
August 9, 2004

4 Die in Accident at Japan Nuclear Power Plant

By JAMES BROOKE
 
 

TOKYO, Aug. 9 — Blasts of non-radioactive steam killed four workers and severely burned seven others today in the first fatal accident at a Japanese nuclear power plant, according to officials.

"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. "We've received a report that there is no impact from radiation on the surrounding environment."

With no official concern over radioactive contamination from the 28-year-old plant, there was no evacuation from the nearby town of Mihama, home to 11,000 people on the Sea of Japan, about 40 miles north of Kyoto, Japan's ancient capital.

But the accident is likely to further shake confidence in nuclear power, just as high oil prices and the Iraq war are making nuclear power more attractive to economic planners.

With the world's third largest nuclear power industry, after the United States and France, Japan relies on nuclear power to generate almost a third of its electricity. Fifty-two nuclear power plants operate in the country.

Heavily dependent on oil imports from the Middle East, Japan has moved aggressively over the past year to work with Russia to develop oil and gas deposits in Siberia.

Plans to build more nuclear power plants in Japan have been slowed as public opinion has become increasingly wary of nuclear power, as evidenced by the number of towns in Japan that have held referendums and vote against building more nuclear plants.

Wariness has been fueled by accidents and by a culture of cover-up where employees have shown a far higher loyalty to their companies than to the public's right to know.

Last summer, the Tokyo Electric Power Company was forced to temporarily close all 17 of its nuclear power plants after admitting 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 staffer at Citizens' Nuclear Information Center, a private nuclear power-watch organization, said in an interview today. "This plant is pretty old, and there are many plants even older."

Today's accident took place in the turbine building of the No. 3 nuclear reactor in Mihama, which was commissioned in November 1976 by the Kansai Electric Power Company.

In the accident, steam believed to measure about 200 degrees Centigrade, or nearly 390 degrees Fahrenheit, spewed into a room just after workers entered to take measurements before a scheduled maintenance shutdown, NHK television reported.

According to the Japanese nuclear safety official, who asked not be identified, it would be impossible for the leaked steam to contain radioactivity as the water in the steam turbines does not come into contact with water used as a coolant for the nuclear reactor.

Kansai Electric Power said it shut the 826,000-kilowatt nuclear generation unit at the facility and was unsure when it would restart.

"We are now investigating the cause," a Kansai Electric official said at a news conference.

"This incident will have no radiation effect on the surrounding environment," Kansai Electric Power said in statement. The company said that two other reactors in the Mihama complex, about 200 miles west of here, are operating normally.

Hiroshi Matsumura, managing director of Kansai Electric, apologized. "It is extremely regrettable," he said at a news conference. "To those who were injured and to the public, we apologize."

The accident took place on the anniversary of the nuclear bombing of Nagasaki in World War II, and political and industry leaders were quick today to assure 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," Prime Minister Junichiro Koizumi told reporters.

Takuya Ito, public relations director of the Federation of Electric Power Companies, worried in an interview that the accident could further dent popular trust in nuclear power, "because these are the first deaths from an accident in a nuclear power plant in operation."

The only other fatalities in the nuclear power industry took place in 1999, at a fuel-reprocessing plant in Tokaimura, northeast of Tokyo. A radiation leak killed two workers, exposed 600 people to low levels of radiation and led to the evacuation of thousands of local 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.

It exposed more than 600 people to radiation and forced around 320,000 to shelter indoors for more than a day. Two of the workers who set off 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 considered dangerous.

WALL STREET JOURNAL
August 9, 2004

Accident at Nuclear Plant
Kills 4, Hurts 7 in Japan

By ANDREW MORSE

TOKYO -- A steam leak at a nuclear-power plant in central Japan killed four people and seriously injured seven others today, in the latest blow to the battered reputation of Japan's nuclear industry.

Authorities said no radiation was released and no public-health hazards resulted from the accident, which occurred when high-pressure steam exploded from a turbine connected to the No. 3 reactor at a Kansai Electric Power Co. facility in Mihama, Fukui Prefecture. The reactor, about 200 miles (320 kilometers) west of Tokyo, automatically shut down during the accident, though two other reactors at the site remained in operation.

A Kansai Electric spokesman said the cause of the accident is still under investigation.

Though the incident appears to have posed no risk to neighboring communities, it is sure to further erode public confidence in an industry that has been plagued by poor training, operational problems and coverups in recent years.

The accident is the worst at a Japanese nuclear-power facility since 1999, when an uncontrolled nuclear chain reaction at a uranium reprocessing plant in Tokaimura, about 71 miles northeast of Tokyo, killed two employees and spewed radioactive neutrons over the surrounding countryside. The Tokaimura incident is widely considered the worst nuclear-power accident since the Chernobyl meltdown in the former Soviet Union in 1986.

The 1999 case contributed to the erosion of public confidence in management of Japan's nuclear plants. Right after the accident, the government played down the dangers but then later ordered more than 300,000 people living within six miles of the plant to stay home. Critical safety equipment was missing at the scene, and local officials lacked the expertise needed to quickly diagnose the accident. The government later said its assessment of the accident's seriousness was "inadequate."

The Japanese nuclear industry's reputation was further damaged last year when Tokyo Electric Power Co. was forced to temporarily shut down its 17 nuclear-power facilities, after acknowledging it had covered up reports showing cracks in the structures of some reactors.

Incidents at Japan's nuclear-power plants, which provide about one-third of the country's energy, have the potential to spill over into international markets because of the country's tremendous need for energy. The shutdowns at Tepco, as the Tokyo power utility is known, led the company to sharply increase its oil purchases for electricity generation and put pressure on global oil prices.

A similar shutdown after Monday's accident could spur another wave of oil buying at a time when prices are already near 21-year highs.

However, a spokesman at the Ministry of Economy, Trade and Industry said there were no plans to shut down other nuclear facilities at this time because of Monday's accident

 

Japan Today

4 dead, 7 injured in nuclear power plant accident


TSUGURA — Four workers were killed and seven others severely burned by a leak of super-heated non-radioactive steam at Mihama nuclear power plant in Fukui Prefecture on Monday, in the latest blow to the country's troubled nuclear industry.

No radioactive leak took place, according to the government's Nuclear and Industry Safety Agency and Kansai Electric Power Co, the owner of the plant.

Doctors at a hospital in the Fukui city of Tsuruga said they did not know what caused the deaths of the four. Witnesses at the plant said the victims had severe burns with their skin and clothes on fire.

In a press conference, the hospital's director Gizo Nakagawara also said the clothes of the four were burned.

KEPCO President Yosaku Fuji left Osaka for power plant by car around 1:30 a.m. Tuesday to deal with the case there.

He expressed regret and apologized for causing concern and to the victims and their families after the accident. KEPCO set up an emergency disaster response task force at its Osaka headquarters.

Fukui prefectural police said they are investigating the incident as a case of professional negligence resulting in injury and death. They said they set up an investigation headquarters at Tsuruga Police Station and assigned 110 investigators to the case.

The latest incident is expected to deal a serious blow to the nuclear industry in Japan, which depends on nuclear power to supply 40% of its electricity.

It is also expected to further heighten public distrust of the country's nuclear industry, which is reeling from past accidents and scandals, such as cover-ups by utility companies of safety violations at their reactors.

In Mihama, local residents expressed anger and anxiety.

Kunio Naya, a 37-year-old fisherman, urged the suspension of the plant's operations and expressed concern that the fishing industry will be affected. "We do not need something like that," he said.

An inn operator also said she is worried that the area's tourism industry would be affected. An employee of the local tourism association said having a nuclear power plant in the area was like "carrying a bomb."

According to information received by the government agency, the steam leak occurred around 3:30 p.m. at a facility housing the turbines for the No. 3 reactor of the plant, located in the town of Mihama, 340 kilometers west of Tokyo.

Several workers, apparently exposed to high-temperature steam, were rushed by ambulance to nearby hospitals. The police have identified five as seriously injured, of which two are in critical condition. Two others sustained minor injuries.

A 65-year-old woman who works at a canteen in the plant said, "Staff rushed into the canteen, screaming. I put in a container all the ice I could find and gave it to them. I don't know what exactly happened. This is the first time an incident like this has happened in my 14 years of work here."

The 826-megawatt pressurized-water reactor was automatically shut down immediately after the incident, according to the agency. KEPCO, Japan's second largest utility, said radiation monitors in the surroundings showed no radioactive leakage.

The agency said in a statement released shortly after the accident that the steam leaked contained no radioactive substances.

Subsequently, no evacuation order was issued to residents nearby, unlike Japan's worst nuclear accident on Sept 30, 1999, at a uranium processing plant in Tokaimura, Ibaraki Prefecture, where two employees died from exposure to extremely high doses of radiation, and 663 others were injured from lower amounts of radiation.

In the 1999 nuclear disaster, about 310,000 residents living within a 10-kilometer radius from the plant were ordered to stay indoors while evacuation orders were issued to residents within a 350-meter radius from the plant.

But Hiroaki Koide, an assistant on nuclear engineering at the Kyoto University Research Reactor Institute, stressed that incident is "serious" despite having no radiation leakage given the number of deaths and injuries.

"The government must do its utmost to ensure safety," Prime Minister Junichiro Koizumi said, adding that the fatalities and injuries were regrettable.

KEPCO said all the victims are employees of Osaka-based Kiuchi Keisoku. The company, specializing in the servicing of power and petroleum plants, said the employees were delivering tools into the site in preparation of a regular inspection, set to start from Saturday, when the accident took place.

Hideyuki Ban of the Tokyo-based Citizens' Nuclear Information Center said that if indeed the company tried to conduct inspections while the reactor was in operation, it means the workers' safety was disregarded for economical efficiency.

The accident occurred at the facility that houses the turbine powered by pressurized steam, which helps generate electricity. Water in this process is heated up to 250-280 C under high pressure and can gush out if leaked, according to experts.

By design, cooling water and steam in this so-called secondary process does not mix with water in the primary loop that centers on the nuclear reactor core.

The exact cause of the leak unknown, but may have been due to damage to turbine devices. KEPCO said it has found a hole in a 56 centimeter diameter pipe that feeds steam in the turbine facility. It suspects strong pressure was applied on the pipe, causing a fracture.

The plant owner said steam erupted from the ceiling of the second floor while work was going on.

All 11 workers, residents of Fukui Prefecture, were on the second floor of the three-story facility, the agency said. KEPCO said there were about 200 people in the facility.

The police identified the four fatalities as Hiroya Takatori, 29, Kazutoshi Nakagawa, 41, Tomoki Iseki, 30, and Eiji Taoka, 46.

Earlier, local firefighters said five people suffered heart and lung failure in the accident.

The government agency sent six inspectors to the site to investigate. The Ministry of Economy, Trade and Industry, later in the day, set up a countermeasures task force at the plant. The Fukui prefecture also set up its own task force.

The No. 3 reactor began service in December 1976.

In February 1991, a tube inside a steam generator at the No. 2 reactor in the same plant broke, resulting in the leak of 55 tons of radioactive water from the primary cooling system into the secondary system.

The 1991 accident was the first time in Japan that an emergency core cooling system was activated.

The Mihama plant was the first nuclear plant built by Kansai Electric. The No. 1 reactor began service in November 1970. (Kyodo News)