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July 23, 2012
Government panel issues Fukushima accident report
A government panel investigating the nuclear accident at the Fukushima Daiichi plant says the operator of the plant lacked a sense of crisis
and imagination for possible tsunami. It says Tokyo Electric Power Company should realize that Japan is prone to natural disasters and change its attitude toward disaster-preparedness.
The panel of government-appointed experts submitted its final report on Monday.
The report criticized the way the utility handled the accident at the Daiichi plant.
It compared the Daiichi plant with another nearby plant, the Fukushima Daini plant, which avoided a nuclear accident although its reactors were also hit by tsunami.
It says workers at the Daini plant kept monitoring the pressure and temperature of the reactor containment vessels, and prepared for alternative ways to inject water.
The panel also examined whether it was appropriate for the Prime Minister at the time, Naoto Kan, to discuss with TEPCO officials whether to inject seawater into the reactors to prevent them from reaching criticality again.
It determined that the government should not have intervened in the matter before the power company had made a decision.
The report also points out that TEPCO had urged a government taskforce on earthquake research to change its wording about a powerful earthquake that hit northeastern Japan 1,100 years ago.
TEPCO said the report could be interpreted as meaning the area was regularly hit by strong earthquakes.
The report says the utility's lack of a sense of crisis was one of the main reasons behind the accident.
The panel is urging the government to continue its probe. It says the cause of the accident has not been fully disclosed.
Apart from the government, private-sector experts and the Diet have also released their own reports on the nuclear accident.
TOKYO (Kyodo) -- A government-appointed panel investigating the Fukushima Daiichi nuclear power plant disaster concluded Monday that Tokyo Electric Power Co. mishandled its response to the crisis and nuclear regulators failed to prepare sufficient disaster-mitigation measures as they were "overly confident" about the safety of nuclear power.
"The utility and regulatory bodies were overly confident that events beyond the scope of their assumptions would not occur...and were not aware that measures to avoid the worst situation were actually full of holes," the panel said in its final report, submitted to Prime Minister Yoshihiko Noda the same day.
The panel was skeptical that the magnitude 9.0 earthquake on March 11, 2011, caused catastrophic damage to key facilities of the Nos. 1 to 3 reactors before tsunami hit the nuclear complex. It called on the state and TEPCO to continue investigating the entire accident, saying many points remain unexplained, such as how radioactive substances leaked outside.
The panel also claimed that then Prime Minister Naoto Kan's involvement in matters to contain the nuclear crisis had "more harmful effects" than changing the situation for the better, because it might have caused "confusion" among workers at the plant or resulted in wrong decisions being made.
Upon receiving the report from the panel's head Yotaro Hatamura, a professor emeritus at the University of Tokyo, Noda said, "We will take all possible measures to prevent recurrences."
The nearly 450-page report centers on the new findings after the panel released its interim report in December, including an analysis on what was wrong about the country's largest utility.
Under the belief that an accident that would result in core meltdown would not occur in Japan, TEPCO had "weak" ability to respond to a crisis because employees were not trained to think flexibly nor deal with a situation in which power supply to multiple reactors is lost for days.
"TEPCO has said that losing nearly all power sources due to an earthquake and tsunami was beyond the scope of assumption. But it was because the company simply decided not to include the event within its assumption, based on a groundless safety myth," the report said. The power loss led to the failure to keep reactors cool and resulted in the meltdown of the Nos. 1 to 3 units.
To highlight the poor response seen at the Fukushima Daiichi complex, the report compared how workers at the Fukushima Daini plant, located about 12 kilometers south of the Daiichi plant, worked to keep cooling the reactors after the quake and tsunami.
For example, the water injection into the Daiichi's No. 3 reactor was suspended for more than six hours because operators on duty manually suspended a high pressure coolant injection system without first preparing an alternative method to cool the reactor.
But at the Daini plant, workers only switched to the next water injection method after first checking whether it would actually function, the report said, noting one employee involved in the Daini plant operation told the panel that "it is a matter of course to make such preparation."
While workers at the Daini plant may have been more composed because external power supply was available there, the handling of the Fukushima Daiichi crisis "lacked appropriateness," the report said.
Nuclear regulators were also obsessed with the safety myth of nuclear power, the panel said. It noted the Nuclear and Industrial Safety Agency strongly opposed a plan in 2006 to enhance preparedness against a nuclear disaster, fearing such a move would raise concerns about the safety of nuclear power among residents living near atomic plants.
The report also gave a poor grade to the government's response to the accident. It questioned whether Kan, the supreme commander, had no other way to address a lack of information about the on-site situation than visiting the plant himself on March 12, the day after the crisis began.
Residents living around the Fukushima plant may also have been able to keep exposure to minimum if the government had effectively used a computer system to predict the spread of radioactive materials, even though data on the damaged reactors were not available, the report said.
The panel's assessment on the System for Prediction of Environmental Emergency Dose Information, or SPEEDI, is different from that presented by another accident investigation panel appointed by the Diet. It said in a report earlier this month that the calculation results by SPEEDI would not have been accurate enough to use as grounds for setting evacuation zones in the absence of plant data.
On the controversial issue of whether TEPCO had an intention to withdraw all workers from the plant in the early days of the crisis, the report said that it was not able to determine that the utility had intended to do so.
The panel also said the utility's analysis of the process of how the reactor cores suffered damage did not necessarily reflect the actual situation. It condemned TEPCO's in-house investigation as "not sufficient in figuring out" what happened in the world's worst nuclear crisis since the 1986 Chernobyl disaster.
Based on the lessons learned from the accident, the panel proposed the government and utilities take safety steps regardless of the probability of tsunami and other events that could have a potentially strong impact, and review disaster reduction measures when important new findings are revealed.