By Jonathan Soble, Michiyo Nakamoto and Gwen Robinson in Tokyo
Published: March 13 2011 10:07 | Last updated: March 13 2011 16:28
Published: March 13 2011 10:07 | Last updated: March 13 2011 16:28
Prime minister Naoto Kan said Japan faced its “worst crisis” since the second world war as the nation grapples with the aftermath of Friday’s earthquake and tsunami and the increasingly serious situation at two nuclear reactors.
His warning came as fears grew that the death toll from the devastating tsunami would ultimately be measured in the tens of thousands.
While rescue workers worked around the clock to find survivors of the tsunami along Japan’s north-east coastline, nuclear experts were trying to prevent a nuclear meltdown at an atomic plant in Fukushima, some 240km north of Tokyo.
Earlier on Sunday, Yukio Edano, the chief government spokesman, said there was a “significant chance” that radioactive fuel rods had partially melted in two reactors [Number One and Number Three] at the Fukushima Daiichi nuclear power facility.
More than 24 hours after engineers began pumping seawater into the Number One reactor, the water level inside its containment vessel and that of the Number Two reactor, remained significantly below levels needed to cool their uranium fuel and prevent a full nuclear meltdown.
Seawater injection at the second reactor began early on Sunday morning, but nuclear safety officials said the water level was not rising as intended. Olli Heinonen, former deputy head of the International Atomic Energy Agency, said the Japanese authorities were “having tremendous trouble”.
“As they long as they can maintain a reasonable level of cooling at the affected reactors, they can avoid partial or full meltdown,” said Mr Heinonen. “But if they fail there will be a steam explosion and the dispersal of radioactive material. It may be a day or two before we know if they have succeeded.”
Mr Heinonen said the nuclear incident was “certainly the most serious since Chernobyl” which occurred in 1986.
On Sunday evening, an official at Japan’s Nuclear and Industrial Safety Agency said fuel rods in the Number One and Number Three reactors were exposed by more than 1.5 metres inside their containment vessels. While coolant-water levels at the Number Two reactor were normal, engineers were preparing seawater injection equipment as a precaution.
Despite the growing concerns about the situation at the Fukushima nuclear plant, Mr Edano said the radiation levels outside the facility, operated by Tokyo Electric Power (Tepco), did not pose a major health threat.
“I am trying to be careful with words,” he said during a televised news conference. “It’s undeniable that some of the fuel may have been deformed, but this is not a situation where the whole core suffers a meltdown.”
More FT video
Adding to problems at the site, hydrogen from vented steam was detected in the Number Three reactor’s outer building, threatening an explosion similar to the one that blew apart the Number One reactor building’s roof and outer walls on Saturday. That blast left the reactor’s core and protective containment vessel intact, Japanese nuclear safety officials insisted.
It remained unclear how much radiation had escaped from the power station, or how far it had spread. Sensors at another nuclear complex 100km to the north picked up levels four times higher than the legal maximum, Japanese media reported.
That plant’s operator, Tohoku Electric Power, said it was “unthinkable” that the radiation came from inside its complex, whose reactors had shut down and cooled normally after the quake.
In the area immediately around Fukushima Daiichi, as many as 160 people may have suffered radiation poisoning, nuclear safety officials said.
A 20km evacuation zone remained in place with at least 170,000 people being forced to leave their homes and television pictures showing rescue workers in white protective suits sweeping evacuees with radiation sensors.
Fukushima Daiichi has six reactors in total. Three were switched off for maintenance when the earthquake struck, and the three others shut down automatically during the quake.
It was during the next step – cooling their still hot fuel rods – that things went wrong. Coolant-water pumps at both of the affected reactors failed, causing water levels inside the reactor vessels to drop, making it difficult for engineers who were unable to keep the fuel rods fully submerged.
Operators were ultimately forced to pump seawater and boron – a chemical that absorbs neutrons released in nuclear reactions – into the vessel.
The emergency measure, begun on Saturday at the Number One reactor and early Sunday at Number Three, appeared to be working, authorities said, although periodic ventilations of contaminated steam continued.
Peak radiation levels in some areas at the edge of the Fukushima site were measured at 1,557 micro-sieverts an hour.
Steven Kerekes, a spokesman for the Nuclear Energy Institute, a US industry group, said normal background radiation is 3,000 micro-sieverts a year, meaning a person exposed to the highest levels at the Fukushima site for two hours would absorb the same amount of radiation that he would normally absorb in 12 months.
“Even if you have a radiation release, although that’s not a good thing, it’s not automatically a harmful thing. It depends on what the level turns out to be,” he said.
Naoto Takeuchi, head of a police earthquake response centre in Miyagi prefecture – one of the worst affected areas – told a news conference he was “certain” that at least 10,000 people had been killed in the prefecture, the closest to the quake’s offshore epicentre.
The number of officially confirmed deaths nationally rose to more than 1,300. While 300,000 people were sheltering in schools, community centres and government buildings.
Around 1.6m households remained without power on Sunday evening. Aftershocks continued to be felt along the country’s Pacific coast and the Meteorological Agency said there was a 70 per cent chance that a quake with a magnitude of 7 or higher would occur in the next three days.
Japan raised its estimate of the magnitude of Friday’s quake to 9.0 from 8.8, although the US Geological Survey’s estimate remained unchanged at 8.9.
With a total of three nuclear power stations in the northeast offline, the government called on manufacturers to keep factories closed and shops to keep neon lights off to save power. Banri Kaeda, industry minister, warned of rolling blackouts in Tokyo and other areas.
Some foreign companies based in Tokyo said they were moving staff to cities further to the southwest, such as Osaka and Fukuoka, until the danger posed by the Fukushima plant could be fully assessed. The spouses and children of some expatriate workers in the capital were leaving the country or were preparing to do so.
Additional reporting by Robert Cookson in Hong Kong
His warning came as fears grew that the death toll from the devastating tsunami would ultimately be measured in the tens of thousands.
“I believe that by coming together as a nation we can overcome this crisis,” Mr Kan said in a televised news conference.
While rescue workers worked around the clock to find survivors of the tsunami along Japan’s north-east coastline, nuclear experts were trying to prevent a nuclear meltdown at an atomic plant in Fukushima, some 240km north of Tokyo.
Earlier on Sunday, Yukio Edano, the chief government spokesman, said there was a “significant chance” that radioactive fuel rods had partially melted in two reactors [Number One and Number Three] at the Fukushima Daiichi nuclear power facility.
More than 24 hours after engineers began pumping seawater into the Number One reactor, the water level inside its containment vessel and that of the Number Two reactor, remained significantly below levels needed to cool their uranium fuel and prevent a full nuclear meltdown.
Seawater injection at the second reactor began early on Sunday morning, but nuclear safety officials said the water level was not rising as intended. Olli Heinonen, former deputy head of the International Atomic Energy Agency, said the Japanese authorities were “having tremendous trouble”.
“As they long as they can maintain a reasonable level of cooling at the affected reactors, they can avoid partial or full meltdown,” said Mr Heinonen. “But if they fail there will be a steam explosion and the dispersal of radioactive material. It may be a day or two before we know if they have succeeded.”
Mr Heinonen said the nuclear incident was “certainly the most serious since Chernobyl” which occurred in 1986.
On Sunday evening, an official at Japan’s Nuclear and Industrial Safety Agency said fuel rods in the Number One and Number Three reactors were exposed by more than 1.5 metres inside their containment vessels. While coolant-water levels at the Number Two reactor were normal, engineers were preparing seawater injection equipment as a precaution.
Despite the growing concerns about the situation at the Fukushima nuclear plant, Mr Edano said the radiation levels outside the facility, operated by Tokyo Electric Power (Tepco), did not pose a major health threat.
“I am trying to be careful with words,” he said during a televised news conference. “It’s undeniable that some of the fuel may have been deformed, but this is not a situation where the whole core suffers a meltdown.”
More FT video
Adding to problems at the site, hydrogen from vented steam was detected in the Number Three reactor’s outer building, threatening an explosion similar to the one that blew apart the Number One reactor building’s roof and outer walls on Saturday. That blast left the reactor’s core and protective containment vessel intact, Japanese nuclear safety officials insisted.
It remained unclear how much radiation had escaped from the power station, or how far it had spread. Sensors at another nuclear complex 100km to the north picked up levels four times higher than the legal maximum, Japanese media reported.
That plant’s operator, Tohoku Electric Power, said it was “unthinkable” that the radiation came from inside its complex, whose reactors had shut down and cooled normally after the quake.
In the area immediately around Fukushima Daiichi, as many as 160 people may have suffered radiation poisoning, nuclear safety officials said.
A 20km evacuation zone remained in place with at least 170,000 people being forced to leave their homes and television pictures showing rescue workers in white protective suits sweeping evacuees with radiation sensors.
Fukushima Daiichi has six reactors in total. Three were switched off for maintenance when the earthquake struck, and the three others shut down automatically during the quake.
It was during the next step – cooling their still hot fuel rods – that things went wrong. Coolant-water pumps at both of the affected reactors failed, causing water levels inside the reactor vessels to drop, making it difficult for engineers who were unable to keep the fuel rods fully submerged.
Operators were ultimately forced to pump seawater and boron – a chemical that absorbs neutrons released in nuclear reactions – into the vessel.
The emergency measure, begun on Saturday at the Number One reactor and early Sunday at Number Three, appeared to be working, authorities said, although periodic ventilations of contaminated steam continued.
Peak radiation levels in some areas at the edge of the Fukushima site were measured at 1,557 micro-sieverts an hour.
Steven Kerekes, a spokesman for the Nuclear Energy Institute, a US industry group, said normal background radiation is 3,000 micro-sieverts a year, meaning a person exposed to the highest levels at the Fukushima site for two hours would absorb the same amount of radiation that he would normally absorb in 12 months.“Even if you have a radiation release, although that’s not a good thing, it’s not automatically a harmful thing. It depends on what the level turns out to be,” he said.
Naoto Takeuchi, head of a police earthquake response centre in Miyagi prefecture – one of the worst affected areas – told a news conference he was “certain” that at least 10,000 people had been killed in the prefecture, the closest to the quake’s offshore epicentre.
The number of officially confirmed deaths nationally rose to more than 1,300. While 300,000 people were sheltering in schools, community centres and government buildings.
Around 1.6m households remained without power on Sunday evening. Aftershocks continued to be felt along the country’s Pacific coast and the Meteorological Agency said there was a 70 per cent chance that a quake with a magnitude of 7 or higher would occur in the next three days.
Japan raised its estimate of the magnitude of Friday’s quake to 9.0 from 8.8, although the US Geological Survey’s estimate remained unchanged at 8.9.
With a total of three nuclear power stations in the northeast offline, the government called on manufacturers to keep factories closed and shops to keep neon lights off to save power. Banri Kaeda, industry minister, warned of rolling blackouts in Tokyo and other areas.
Some foreign companies based in Tokyo said they were moving staff to cities further to the southwest, such as Osaka and Fukuoka, until the danger posed by the Fukushima plant could be fully assessed. The spouses and children of some expatriate workers in the capital were leaving the country or were preparing to do so.
Additional reporting by Robert Cookson in Hong Kong
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