Japan’s nuclear crisis leads to dangerous spike in radiation levels
Gallery: Japan’s nuclear crisis: Japan battles to prevent a nuclear catastrophe and to care for millions of people without power or water in its worst crisis since World War II.
Japan’s nuclear emergency turned more dire on Tuesday after the third explosion in four days rocked the seaside Fukushima Daiichi complex and fire briefly raged in a storage facility for spent fuel rods at a fourth, previously unaffected reactor.
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Graphic: Track the status of the nuclear crisis in Japan and see what lead to Saturday’s explosion.
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Video: Residents within 19 miles of a stricken Japanese nuclear power plant have been ordered indoors when radiation levels soared after an explosion fire. Officials said a fuel storage pond at Unit 4 had been burning. (March 15)
Three hours after the explosion, the radiation level at the plant measured 11,930 micro sieverts per hour — several times the amount a person can safely be exposed to in one year. Radiation levels shrank dramatically within the next six hours, to 496 micro sieverts per hour, which government spokesman Yukio Edano called “much higher than the normal level . . . but one that causes no harm to human health.”
His statement brought little solace to the country’s frantic residents, who are frustrated by vague statements from Toyko Electric Power Co. officials and worried that government assurances may ultimately prove false.
Officials from Tokyo Electric, owner of the nuclear complex, said radioactive substances were emitted after an explosion in the unit 2 reactor at 6:14 a.m. (5:14 p.m. Monday in Washington). The blast took place near or in the suppression pool, which traps and cools radioactive elements from the containment vessel, officials said. The explosion appeared to have damaged valves and pipes, possibly creating a path for radioactive materials to escape.
While the fire at the fourth reactor had been extinguished, Japanese officials told the International Atomic Energy Agency that because of the blaze “radioactivity is being released directly into the atmosphere,” the agency said.
A grave Prime Minister Naoto Kan told the nation that radiation already had spread from the reactors and there was “still a very high risk of further radioactive material escaping.” He urged people within 12.5 miles to evacuate the area, and said those within 19 miles of the plant should remain indoors.
He also asked for calm.
Tokyo Electric, which during the weekend said it had 1,400 people working at the complex, evacuated all but 50 workers after the explosion. Kan hailed those workers who remained at the plant, who he said “are putting themselves in a very dangerous situation.”
Higher-than-normal radiation levels were detected in Tokyo, roughly 150 miles from Fukushima. Kanagawa, a prefecture south of Tokyo, recorded radiation at nine times the usual level. In Ibaraki, roughly 70 miles from Tokyo, levels were briefly 100 times the normal measure, according to the Kyodo news agency.
In each case, officials said that exposure to those levels of radiation would not pose an immediate danger to human health.
A no-fly zone was declared covering a 19-mile radius around the Fukushima Daiichi facility. For most of the day, winds blew in a southeasterly direction, pushing the plume of radioactivity toward the Pacific Ocean.
Late Tuesday afternoon, Japanese authorities said the situation at Fukushima Daiichi had marginally improved — though it remains dangerous. In addition to putting out the fire at unit 4, workers were closer to stabilizing units 1 and 3, keeping the fuel rods under the necessary cooling water. Edano said that it was too early to tell if workers’ emergency cooling efforts are working for unit 2.
“There is no manual to this kind of incident. I believe on the ground things are chaotic,” Takayuki Terai, professor of nuclear engineering at the University of Tokyo. “But in essence, they just have to put water into the reactors continuously and cool them down and contain them.”
Amid the four-day-long emergency at the Fukushima Daiichi plant, Japan’s public has grown skeptical about the reliability of official information, criticizing Tokyo Electric officials in particular for their vague answers during news conferences.
Kan himself was not briefed on the Tuesday morning explosion until after it had been reported on television. According to a Kyodo reporter who overheard the conversation, Kan later grilled the company representatives, asking, “What the hell is going on?”
During a midmorning news conference, four Tokyo Electric officials revealed almost no information about the blast.
Japan’s usually deferential news media turned vicious, asking, “What does this mean?”
“We want answers, not apologies,” one reporter said.
Tuesday began with the fire that broke out in a pool storing spent fuel rods at the base of unit 4, which had been shut down for inspection before last Friday’s earthquake. Experts said the fire most likely broke out because the pool water had run low or dry, allowing the rods to overheat. Radioactive substances spewed outside from the fire, officials said, because the structure housing the pool was damaged by Monday’s explosion at unit 3.
Half an hour later, the explosion at unit 2 took place. Experts said that, unlike the two previous explosions that destroyed outer buildings, this explosion might have damaged portions of the containment vessel designed to bottle up radioactive materials in the event of an emergency.
The explosion was followed by a brief drop in pressure in the vessel and a spike in radioactivity outside the reactor to levels more than eight times the recommended limit for what people should receive in a year, the company said. Japanese government officials later said it was unclear whether the spent fuel fire or the explosion had caused the spike in radiation.
The new setbacks came on the heels of a difficult Monday at Fukushima Daiichi unit 2, one of six reactors at the site. Utility officials there reported that four out of five water pumps being used to flood the reactor had failed and that the other pump had briefly stopped working. As a result, the company said, the fuel rods, normally covered by water, were completely exposed for 140 minutes.
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