'Devil's chain reaction' feared after Japan quake

An empty shopping street in Tomioka town.
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An empty shopping street in Tomioka town.
Houses destroyed by the tsunami in Tomioka.
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Houses destroyed by the tsunami in Tomioka.
A fishing boat and a car swept away by the tsunami.
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A fishing boat and a car swept away by the tsunami.
Abandoned wheelchairs outside Okuma Town Health Center in Okuma town.
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Abandoned wheelchairs outside Okuma Town Health Center in Okuma town.
An abandoned child's bicycle and houses destroyed by the tsunami in Tomioka town.
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An abandoned child's bicycle and houses destroyed by the tsunami in Tomioka town.
Road cracks caused by an earthquake in an empty shopping street in Tomioka.
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Road cracks caused by an earthquake in an empty shopping street in Tomioka.
A house destroyed by the 2011 tsunami is seen in the Fukushima exclusion zone.
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A house destroyed by the 2011 tsunami is seen in the Fukushima exclusion zone.
A weed is seen growing out of the cracks at a petrol station on Route 6.
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A weed is seen growing out of the cracks at a petrol station on Route 6.
Fallen gravestones at a cemetery in Namie town inside the Fukushima exclusion zone.
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Fallen gravestones at a cemetery in Namie town inside the Fukushima exclusion zone.
An ostrich which had escaped from a farm in Tomioka town.
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An ostrich which had escaped from a farm in Tomioka town.
The crippled Fukushima Daiichi nuclear power plant's No.3 reactor building.
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The crippled Fukushima Daiichi nuclear power plant's No.3 reactor building.

Japan's prime minister ordered workers to remain at the tsunami-crippled Fukushima nuclear plant last March as fears mounted of a "devil's chain reaction" that would force tens of millions of people to flee Tokyo, a new investigative report shows.

Then-premier Naoto Kan and his staff began referring to a worst case scenario that could threaten Japan's existence as a nation around three days after the March 11 earthquake and tsunami, according to the report by a panel set up by a private think-tank.

That was when fears mounted that thousands of spent fuel rods stored at a damaged reactor would melt and spew radiation after a hydrogen explosion at an adjacent reactor building, according to the panel report.

Yukio Edano, then Japan's top government spokesman, told the panel that at the height of tension he feared a "devil's chain reaction" in which the Fukushima Daiichi plant and the nearby Fukushima Daini facility, as well as the Tokai nuclear plant, spiralled out of control, putting the capital at risk.

Kan, who stepped down last September, came under fire for his handling of the crisis, including flying over the plant by helicopter the morning after the disasters hit - a move some critics said contributed to a delay in the operator's response.

In an interview with Reuters this month, the 65-year-old Kan said he was haunted by the spectre of a crisis spiralling out of control and forcing the evacuation of the Tokyo greater metropolitan area, 240km away and home to some 35 million people.

After the quake and tsunami struck, three reactors melted down and radiation spewed widely through eastern Japan, forcing tens of thousands of residents to evacuate from near the plant.

Plant operator Tokyo Electric Power Co, known as Tepco, managed to avert the worst scenario by pumping water, much of it from the sea, into Daiichi's damaged reactors and spent fuel pools. The reactors were stabilised by December.

A year after the disaster, however, Fukushima Daiichi still resembles a vast wasteland. High radiation levels hamper a cleanup that is expected to take decades.

The damaged 40-metre-high No.2 reactor building stands like a bird's nest of twisted steel beams. A Tepco official who accompanied foreign media to the plant on Tuesday said metal debris was being painstakingly removed by giant cranes and pincers as radiation doses were too high for workers.

Another challenge is keeping a new cooling system, built from a myriad of technologies and prone to breaking down, running without major glitches.

"An earthquake or tsunami like the ones seen a year ago could be a source of trouble for these (cooling) systems. But we are currently reinforcing the spent fuel pool and making the sea walls higher against tsunamis," Takeshi Takahashi, the Daiichi plant's manager, told reporters. "A series of back up systems is also being put in place in case one fails."

Confused media reports at the time of the accident said Tepco had threatened to withdraw workers from the plant, but that Kan ordered them to keep staff on-site.

"Now Tepco is saying there was no request for a complete pullout, that it only asked for a partial withdrawal. The truth may never come out, but as a result, 50 Tepco staff stayed behind and ... the worst case scenario was averted," panel chief Koichi Kitazawa told Reuters before the report's release.

STRONG SENSE OF CRISIS


How many of those who stayed were volunteers is a mystery.

"An order was likely given for full-time employees to stay behind. We may eventually find out who volunteered to stay, but the impression from our investigation is that they are under strict orders to remain silent."

The six-member panel is one of several probing the disaster caused by the quake and tsunami that knocked out cooling systems at Fukushima Daiichi and triggered meltdowns of nuclear fuel in the worst radiation crisis since Chernobyl. Since September, it has interviewed more than 300 people, including Kan and Edano, but no Tepco executives.

Kan's administration, Tepco and nuclear regulators have all faced criticism, both for a confused response and for failing to come clean on the extent of the crisis in the early days, undermining public trust in Japan's leaders and bureaucracy.

The panel lauded Kan for keeping the workers on site, but added that the premier, who had tangled with bureaucrats in the past and did not trust those around him, was too hands on in dealing with the crisis.

"Overall, he failed to pass the test," Kitazawa told a news conference after the report was issued.

Edano, overnight NZ time, acknowledged he had feared the worst around March 14-15. "I was working with a strong sense of crisis that under various circumstances, such a thing may be possible," he told a news conference in Tokyo.

But he defended his silence as government spokesman.

"I shared all information. Back then, I was not in a position where I, as someone who is not an expert, could irresponsibly speak about my own personal impressions and my sense of crisis," he told a news conference.

"I conveyed assessments and decisions of the government, government agencies and experts," he added.

The panel report said some of Kan's seemingly inexplicable behaviour stemmed from his belief that Tepco was going to abandon the plant and the accident would spiral out of control.

An irate Kan blasted Tepco on March 15, yelling: "What the hell is going on" in an outburst overheard by a Kyodo news reporter and quickly reported around the globe. "I want you all to be determined," he was quoted as telling utility executives.

The utility ultimately left a corps of workers who were dubbed the "Fukushima Fifty" by media and won admiration at home and abroad as they risked their lives to contain the crisis, although their names were never made public.

Four-year-old girl Saki Watanabe is tested for possible nuclear radiation at an evacuation centre in Koriyama.
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Four-year-old girl Saki Watanabe is tested for possible nuclear radiation at an evacuation centre in Koriyama.
A girl wearing a hat sits in her stroller as she takes part in an anti-nuclear protest with her mother in Tokyo.
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A girl wearing a hat sits in her stroller as she takes part in an anti-nuclear protest with her mother in Tokyo.
The crippled Fukushima Daiichi Nuclear Power plant is seen in Fukushima Prefecture in this undated handout photo.
3 of 23Supplied
The crippled Fukushima Daiichi Nuclear Power plant is seen in Fukushima Prefecture in this undated handout photo.
A man is tested for radiation in Koriyama.
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A man is tested for radiation in Koriyama.
Hiromi Kobayashi, who is eight months pregnant, is tested for possible nuclear radiation exposure at an evacuation center in Koriyama.
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Hiromi Kobayashi, who is eight months pregnant, is tested for possible nuclear radiation exposure at an evacuation center in Koriyama.
TEPCO's crippled Fukushima Daiichi Nuclear Power Plant No.4 reactor is seen in this still image taken from a video shot by an unmanned helicopter on April 10, 2011.
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TEPCO's crippled Fukushima Daiichi Nuclear Power Plant No.4 reactor is seen in this still image taken from a video shot by an unmanned helicopter on April 10, 2011.
TEPCO's crippled Fukushima Daiichi Nuclear Power Plant No. 3 reactor in Fukushima prefecture, northern Japan is seen in this still image taken from a video shot by an unmanned helicopter on April 10, 2011.
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TEPCO's crippled Fukushima Daiichi Nuclear Power Plant No. 3 reactor in Fukushima prefecture, northern Japan is seen in this still image taken from a video shot by an unmanned helicopter on April 10, 2011.
Japan Maritime Self-Defense Force personnel, wearing protective suits, operate on JMSDF auxiliary multi-purpose support ship Hiuchi near the Tokyo Electric Power Co.'s Fukushima Daiichi nuclear power plant.
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Japan Maritime Self-Defense Force personnel, wearing protective suits, operate on JMSDF auxiliary multi-purpose support ship Hiuchi near the Tokyo Electric Power Co.'s Fukushima Daiichi nuclear power plant.
Yumi Sugiura, centre, and her husband, who evacuated from Iitate town in Fukushima, look at a list of detected nuclear radiation levels in communities at a welfare center in Yamagata, northern Japan.
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Yumi Sugiura, centre, and her husband, who evacuated from Iitate town in Fukushima, look at a list of detected nuclear radiation levels in communities at a welfare center in Yamagata, northern Japan.
Yumi Sugiura, who evacuated from Iitate town in Fukushima, receives a screening test for traces of nuclear radiation at a welfare center in Yamagata, northern Japan.
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Yumi Sugiura, who evacuated from Iitate town in Fukushima, receives a screening test for traces of nuclear radiation at a welfare center in Yamagata, northern Japan.
Steam rises from the No.3 reactor at the Fukushima Dai-ichi nuclear power complex, March 16.
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Steam rises from the No.3 reactor at the Fukushima Dai-ichi nuclear power complex, March 16.
Damage to the No. 4 reactor at the Fukushima Daiichi nuclear power complex.
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Damage to the No. 4 reactor at the Fukushima Daiichi nuclear power complex.
Damage to the No. 4 reactor at the Fukushima Daiichi nuclear power complex.
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Damage to the No. 4 reactor at the Fukushima Daiichi nuclear power complex.
Medical staff use a Geiger counter to screen a woman for possible radiation exposure at a public welfare centre in Hitachi City, Ibaraki.
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Medical staff use a Geiger counter to screen a woman for possible radiation exposure at a public welfare centre in Hitachi City, Ibaraki.
Tokyo Electric Co. employees in charge of public relations use a photo of the Fukushima Daiichi nuclear complex to explain the situation during a press conference.
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Tokyo Electric Co. employees in charge of public relations use a photo of the Fukushima Daiichi nuclear complex to explain the situation during a press conference.
The No.3 nuclear reactor of the Fukushima Daiichi nuclear plant is seen burning after a blast following an earthquake and tsunami in this satellite image.
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The No.3 nuclear reactor of the Fukushima Daiichi nuclear plant is seen burning after a blast following an earthquake and tsunami in this satellite image.
A doctor checks uses a giger counter to check the level of radiation on a woman while a soldier in gas mask looks on at a radiation treatment centre in Nihonmatsu city in Fukushima prefecture.
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A doctor checks uses a giger counter to check the level of radiation on a woman while a soldier in gas mask looks on at a radiation treatment centre in Nihonmatsu city in Fukushima prefecture.
Smoke rises from Fukushima Daiichi nuclear power complex in this still image from video footage.
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Smoke rises from Fukushima Daiichi nuclear power complex in this still image from video footage.
An official scans for signs of radiation in Nihonmatsu City after radiation leaked from the earthquake-damaged Fukushima Daini nuclear station.
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An official scans for signs of radiation in Nihonmatsu City after radiation leaked from the earthquake-damaged Fukushima Daini nuclear station.
Futaba Kosei Hospital patients disembark after being evacuated from a hospital near the troubled Fukushima Dai-ichi nuclear complex. They might have been exposed to radiation while waiting for evacuation.
20 of 23Associated Press
Futaba Kosei Hospital patients disembark after being evacuated from a hospital near the troubled Fukushima Dai-ichi nuclear complex. They might have been exposed to radiation while waiting for evacuation.
Officials in protective gear stand next to people from the evacuation area near the Fukushima Daini nuclear plant.
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Officials in protective gear stand next to people from the evacuation area near the Fukushima Daini nuclear plant.
An official in protective gear talks to a woman who is from the evacuation area near the Fukushima Daini nuclear plant.
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An official in protective gear talks to a woman who is from the evacuation area near the Fukushima Daini nuclear plant.
The damaged roof of reactor number No. 1 at the Fukushima Daiichi nuclear plant after an explosion that blew off the upper part of the structure.
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The damaged roof of reactor number No. 1 at the Fukushima Daiichi nuclear plant after an explosion that blew off the upper part of the structure.
The destruction in Natori City, Miyagi Prefecture, northeastern Japan days after the 2011 tsunami.
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The destruction in Natori City, Miyagi Prefecture, northeastern Japan days after the 2011 tsunami.
Workers and rescuers amid debris of buildings wrecked by last week's earthquake and tsunami in Natori City, Miyagi Prefecture, northeastern Japan.
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Workers and rescuers amid debris of buildings wrecked by last week's earthquake and tsunami in Natori City, Miyagi Prefecture, northeastern Japan.
A resident braves the wreckage of a house in in Natori City, Miyagi Prefecture, northeastern Japan.
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A resident braves the wreckage of a house in in Natori City, Miyagi Prefecture, northeastern Japan.
A survivor walks among the remains of buildings in Minamisanriku town, Miyagi Prefecture in northern Japan.
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A survivor walks among the remains of buildings in Minamisanriku town, Miyagi Prefecture in northern Japan.
A boy searches for clothes among items donated by people at a Red Cross office in Otsuchi, Iwate Prefecture in northern Japan.
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A boy searches for clothes among items donated by people at a Red Cross office in Otsuchi, Iwate Prefecture in northern Japan.
A locomotive is found 30 metres away from the railway in Minamisanriku town, Miyagi Prefecture in northern Japan.
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A locomotive is found 30 metres away from the railway in Minamisanriku town, Miyagi Prefecture in northern Japan.
A fireflighter sprays water to clean a street in the debris in Yamada.
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A fireflighter sprays water to clean a street in the debris in Yamada.
Survivors of Friday's earthquake and tsunami walk with their belongings by the rubble in Kamaishi.
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Survivors of Friday's earthquake and tsunami walk with their belongings by the rubble in Kamaishi.
A girl searches through the rubble near her home in Kamashi.
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A girl searches through the rubble near her home in Kamashi.
Members of the Japan Self-Defense Force listen arrive at the devastated residential area in Otsuchi as heavy snow falls March 16.
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Members of the Japan Self-Defense Force listen arrive at the devastated residential area in Otsuchi as heavy snow falls March 16.
Heavy snow falls on rubble and rescue workers at a devastated factory area hit by an earthquake and tsunami in Sendai, northern Japan.
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Heavy snow falls on rubble and rescue workers at a devastated factory area hit by an earthquake and tsunami in Sendai, northern Japan.
Soldiers and a rescue worker carry a body through Kesennuma City on March 15, 2011.
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Soldiers and a rescue worker carry a body through Kesennuma City on March 15, 2011.
A firemen goes through pictures found in ruins of the devastated residential area of tsunami hit Otsuchi March 15.
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A firemen goes through pictures found in ruins of the devastated residential area of tsunami hit Otsuchi March 15.
Rescue workers arrive at the devastated residential area of Otsuchi, where an entire village was wiped out, as the forest burns above the town March 15, 2011.
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Rescue workers arrive at the devastated residential area of Otsuchi, where an entire village was wiped out, as the forest burns above the town March 15, 2011.
A car on a roof in Sendai.
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A car on a roof in Sendai.
The search for victims around a ship swept away by a tsunami in Higashimatsushima City, Miyagi Prefecture.
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The search for victims around a ship swept away by a tsunami in Higashimatsushima City, Miyagi Prefecture.
A destroyed building in Tanohata Village, Iwate Prefecture in northern Japan.
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A destroyed building in Tanohata Village, Iwate Prefecture in northern Japan.
Japan Self-Defense Forces officers search for victims in Higashimatsushima City, Miyagi Prefecture in northern Japan, after an earthquake and tsunami struck the area, March 14.
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Japan Self-Defense Forces officers search for victims in Higashimatsushima City, Miyagi Prefecture in northern Japan, after an earthquake and tsunami struck the area, March 14.
A Mitsubishi F-2 fighter aircraft which was swept by the tsunami into a building at Matsushima base in Higashimatsushima, Iwate Prefecture in northern Japan, March 14, 2011.
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A Mitsubishi F-2 fighter aircraft which was swept by the tsunami into a building at Matsushima base in Higashimatsushima, Iwate Prefecture in northern Japan, March 14, 2011.
FEARED CRISIS WOULD SPIRAL OUT OF CONTROL: Former Japanese Prime Minister Naoto Kan ordered workers to stay at the Fukushima Daiichi nuclear plant after a massive earthquake and tsunami on March 11 last year.
Reuters
FEARED CRISIS WOULD SPIRAL OUT OF CONTROL: Former Japanese Prime Minister Naoto Kan ordered workers to stay at the Fukushima Daiichi nuclear plant after a massive earthquake and tsunami on March 11 last year.

Reuters