The unfolding disaster at the Fukushima nuclear plant follows decades of falsified safety reports, fatal accidents and underestimated earthquake risk in Japan’s atomic power industry.
The destruction caused by last week’s 9.0 earthquake and tsunami comes less than four years after a 6.8 quake shut the world’s biggest atomic plant, also run by Tokyo Electric Power Co. In 2002 and 2007, revelations the utility had faked repair records forced the resignation of the company’s chairman and president, and a three-week shutdown of all 17 of its reactors.
With almost no oil or gas reserves of its own, nuclear power has been a national priority for Japan since the end of World War II, a conflict the country fought partly to secure oil supplies. Japan has 54 operating nuclear reactors -- more than any other country except the U.S. and France -- to power its industries, pitting economic demands against safety concerns in the world’s most earthquake-prone country.
Nuclear engineers and academics who have worked in Japan’s atomic power industry spoke in interviews of a history of accidents, faked reports and inaction by a succession of Liberal Democratic Party governments that ran Japan for nearly all of the postwar period.
Katsuhiko Ishibashi, a seismology professor at Kobe University, has said Japan’s history of nuclear accidents stems from an overconfidence in plant engineering. In 2006, he resigned from a government panel on reactor safety, saying the review process was rigged and “unscientific.”
In an interview in 2007 after Tokyo Electric’s Kashiwazaki nuclear plant was struck by an earthquake, Ishibashi said fundamental improvements were needed in engineering standards for atomic power stations, without which Japan could suffer a catastrophic disaster.
“We didn’t learn anything,” Ishibashi said in a phone interview this week. “Nuclear power is national policy and there’s a real reluctance to scrutinize it.”
To be sure, Japan’s record isn’t the worst. The International Atomic Energy Agency rates nuclear accidents on a scale of zero to seven, with Chernobyl in the former Soviet Union rated seven, the most dangerous. Fukushima, where the steel vessels at the heart of the reactors have so far not ruptured, is currently a class five, the same category as the 1979 partial reactor meltdown at Three Mile Island in the U.S.
“The key thing here is that this is not another Chernobyl,” said Ken Brockman, a former director of nuclear installation safety at the IAEA in Vienna. “Containment engineering has been vindicated. What has not been vindicated is the site engineering that put us on a path to accident.”
The 40-year-old Fukushima plant, built in the 1970s when Japan’s first wave of nuclear construction began, stood up to the country’s worst earthquake on record March 11 only to have its power and back-up generators knocked out by the 7-meter tsunami that followed.
Lacking electricity to pump water needed to cool the atomic core, engineers vented radioactive steam into the atmosphere to release pressure, leading to a series of explosions that blew out concrete walls around the reactors.
Radiation readings spiked around Fukushima as the disaster widened, forcing the evacuation of 200,000 people and causing radiation levels to rise on the outskirts of Tokyo, 135 miles (210 kilometers) to the south, with a population of 30 million.
Back-up diesel generators that might have averted the disaster were positioned in a basement, where they were overwhelmed by waves.
“This in the country that invented the word Tsunami,” said Brockman, who also worked at the U.S. Nuclear Regulatory Commission. “Japan is going to have a look again at its regulatory process and whether it’s intrusive enough.”
The cascade of events at Fukushima had been foretold in a report published in the U.S. two decades ago. The 1990 report by the U.S. Nuclear Regulatory Commission, an independent agency responsible for safety at the country’s power plants, identified earthquake-induced diesel generator failure and power outage leading to failure of cooling systems as one of the “most likely causes” of nuclear accidents from an external event.
While the report was cited in a 2004 statement by Japan’s Nuclear and Industrial Safety Agency, it seems adequate measures to address the risk were not taken by Tokyo Electric, said Jun Tateno, a former researcher at the Japan Atomic Energy Agency and professor at Chuo University.
“It’s questionable whether Tokyo Electric really studied the risks,” Tateno said in an interview. “That they weren’t prepared for a once in a thousand year occurrence will not go over as an acceptable excuse.”
Hajime Motojuku, a utility spokesman, said he couldn’t immediately confirm whether the company was aware of the report.
All six boiling water reactors at the Fukushima Dai-Ichi plant were designed by General Electric Co. and the company built the No. 1, 2 and 6 reactors, spokeswoman Emily Caruso said in an e-mail response to questions. The No. 1 reactor went into commercial operation in 1971.
Toshiba Corp. built 3 and 5. Hitachi Ltd., which folded its nuclear operations into a venture with GE known as Hitachi-GE Nuclear Energy Ltd. in 2007, built No. 4.
All the reactors meet the U.S. Nuclear Regulatory Commission requirements for safe operation during and after an earthquake for the areas where they are licensed and sited, GE said on its website.
Mitsuhiko Tanaka, 67, working as an engineer at Babcock Hitachi K.K., helped design and supervise the manufacture of a $250 million steel pressure vessel for Tokyo Electric in 1975. Today, that vessel holds the fuel rods in the core of the No. 4 reactor at Fukushima’s Dai-Ichi plant, hit by explosion and fire after the tsunami.
Tanaka says the vessel was damaged in the production process. He says he knows because he orchestrated the cover-up. When he brought his accusations to the government more than a decade later, he was ignored, he says.
The accident occurred when Tanaka and his team were strengthening the steel in the pressure vessel, heating it in a furnace to more than 600 degrees Celsius (1,112 degrees Fahrenheit), a temperature that melts metal. Braces that should have been inside the vessel during the blasting were either forgotten or fell over. After it cooled, Tanaka found that its walls had warped.
‘Felt Like a Hero’
The law required the flawed vessel be scrapped, a loss that Tanaka said might have bankrupted the company. Rather than sacrifice years of work and risk the company’s survival, Tanaka used computer modeling to devise a way to reshape the vessel so that no one would know it had been damaged. He did that with Hitachi’s blessings, he said.
“I saved the company billions of yen,” Tanaka said in an interview March 12, the day after the earthquake. Tanaka says he got a 3 million yen bonus ($38,000) from Hitachi and a plaque acknowledging his “extraordinary” effort in 1974. “At the time, I felt like a hero.”
That changed with Chernobyl. Two years after the world’s worst nuclear accident, Tanaka went to the Ministry of Economy, Trade and Industry to report the cover-up he’d engineered more than a decade earlier. Hitachi denied his accusation and the government refused to investigate.
‘No Safety Problem’
Kenta Takahashi, an official at the NISA’s Power Generation Inspection Division, said he couldn’t confirm whether the agency’s predecessor, the Agency for Natural Resources and Energy, conducted an investigation into Tanaka’s claim.
In 1988, Hitachi met with Tanaka to discuss the work he had done to fix the dent in the vessel. They concluded that there was no safety problem, said Hitachi spokesman Yuichi Izumisawa. “We have not revised our view since then,” Izumisawa said.
In 1990, Tanaka wrote a book called “Why Nuclear Power Is Dangerous” that detailed his experiences.
Tokyo Electric in 2002 admitted it had falsified repair reports at nuclear plants for more than two decades. Chairman Hiroshi Araki and President Nobuyama Minami resigned to take responsibility for hundreds of occasions in which the company had submitted false data to the regulator.
Then in 2007, the utility said it hadn’t come entirely clean five years earlier. It had concealed at least six emergency stoppages at its Fukushima Dai-Ichi power station and a “critical” reaction at the plant’s No. 3 unit that lasted for seven hours.
Tokyo Electric ignored warnings about the tsunami risks that caused the crisis at Fukushima, Tatsuya Ito, who represented Fukushima prefecture in the national parliament from 1991 to 2003, said in a March 16 telephone interview.
The Fukushima Dai-Ichi plant was only designed to withstand a 5.7-meter tsunami, not the 7-meter wall of water generated by last week’s earthquake or the 6.4-meter tsunami that struck neighboring Miyagi prefecture after the Valdiva earthquake in 1960, Ito said.
The dangers posed by a tsunami the size of the one generated by the 9.5-magnitude Valdiva temblor off Chile are described in a 2002 report by the Japan Society of Civil Engineers, Ito said.
“Tokyo Electric brought this upon itself,” said Ito, who now heads the National Center for the Citizens’ Movement Against the Nuclear Threat, based in Tokyo. “This accident unfolded as expected.”
Ito said he has met Tepco employees to discuss his concerns at least 20 times since 2003 and sent a formal letter to then-president Tsunehisa Katsumata in 2005.
“We are prioritizing the safety of the plant and are not at a point where we can reflect upon and properly assess the root causes,” said Naoki Tsunoda, a Tokyo Electric spokesman in Tokyo. He said he couldn’t immediately confirm the exchanges made between Ito and the company.
Kansai Electric Power Co., the utility that provides Osaka with electricity, said it also faked nuclear safety records. Chubu Electric Power Co., Tohoku Electric Power Co. and Hokuriku Electric Power Co. said the same.
Only months after that second round of revelations, an earthquake struck a cluster of seven reactors run by Tokyo Electric on Japan’s north coast. The Kashiwazaki Kariwa nuclear plant, the world’s biggest, was hit by a 6.8 magnitude temblor that buckled walls and caused a fire at a transformer. About 1.5 liters (half gallon) of radioactive water sloshed out of a container and ran into the sea through drains because sealing plugs hadn’t been installed.
While there were no deaths from the accident and the IAEA said radiation released was within authorized limits for public health and environmental safety, the damage was such that three of the plant’s reactors are still offline.
After the quake, Trade Minister Akira Amari said regulators hadn’t properly reviewed Tokyo Electric’s geological survey when they approved the site in 1974.
The world’s biggest nuclear power plant had been built on an earthquake fault line that generated three times as much seismic acceleration, or 606 gals, as it was designed to withstand, the utility said. One gal, a measure of shock effect, represents acceleration of 1 centimeter (0.4 inch) per square second.
After Hokuriku Electric’s Shika nuclear power plant in Ishikawa prefecture was rocked by a 6.9 magnitude quake in March 2007, government scientists found it had been built near an earthquake fault that was more than twice as long as regulators deemed threatening.
“Regulators just rubber-stamp the utilities’ reports,” Takashi Nakata, a former Hiroshima Institute of Technology seismologist and an anti-nuclear activist, said at the time.
While Japan had never suffered a failure comparable to Chernobyl, the Fukushima disaster caps a decade of fatal accidents.
Two workers at a fuel processing plant were killed by radiation exposure in 1999, when they used buckets, instead of the prescribed containers, to eye-ball a uranium mixture, triggering a chain-reaction that went unchecked for 20 hours.
Regulators failed to ensure that safety alarms were installed at the plant run by Sumitomo Metal Mining Co. because they believed there was “no possibility” of a major accident at the facility, according to an analysis by the NRC in the U.S. The report said there were ‘indications’ the company instructed workers to take shortcuts, without regulatory approval.
In 2004, an eruption of super-heated steam from a burst pipe at a reactor run by Kansai Electric killed five workers and scalded six others. A government investigation showed the burst pipe section had been omitted from safety checklists and had not been inspected for the 28 years the plant had been in operation.
Unlike France and the U.S., which have independent regulators, responsibility for keeping Japan’s reactors safe rests with the same body that oversees the effort to increase nuclear power generation: the Trade Ministry. Critics say that creates a conflict of interest that may hamper safety.
‘Scandals and Lies’
“What is necessary is a qualified, well-funded, independent regulator,” said Seth Grae, chief executive officer of Lightbridge Corp., a nuclear consultant in the U.S. “What happens when you have an independent regulatory agency, you can have a utility that has scandals and lies, but the regulator will yank its licensing approvals,” he said.
Tanaka says his book on the experiences he had with the nuclear power industry went out of print in 2000. His publisher called on March 13, two days after the Fukushima earthquake, and said they were starting another print run.
“Maybe this time people will listen,” he said.