Reporting from Sendai and Tokyo, Japan Fresh setbacks, including another blaze at a crippled reactor, bedeviled Japanese authorities Wednesday as they struggled to contain the world's worst nuclear crisis in a quarter of a century, and survivors of the devastating earthquake and tsunami suffered through shortages, bitter cold and overnight snowfall.
Troubling new estimates emerged of the extent of damage at the Fukushima No. 1 (Daiichi) nuclear plant about 150 miles north of Tokyo.
Elevated radiation levels detected a day earlier in the vicinity of the plant imposed a creeping sense of isolation, with greater numbers of foreigners leaving, rescue crews mindful of exit routes and international flights being diverted away from the capital.
Photos: Scenes of earthquake destruction
Tens of thousands of residents within a 20-mile radius of the plant were essentially trapped indoors for a second day Wednesday, urged again by authorities to avoid going out unless it was an emergency. That posed a conundrum for those who have already been scrambling to obtain basic necessities; food, water and medicine have all been hard to come by in the area hit by Friday's magnitude 9 quake and the tsunami that followed.
"Yesterday we ate a bit of rice and one egg," said Yoshiko Tsuzuki, 55, a homemaker standing beside her husband and 16-year old daughter in a line outside a grocery store near the battered city of Sendai. "We're hungry. I want to buy water and anything to eat. We need everything."
It remained unclear why a country renowned for its efficiency has been unable to marshal convoys of supply trucks into the disaster area, as China did after its 2008 earthquake. Though military vehicles were evident, few emergency supplies were seen on the major arteries from Tokyo into the hard-hit Tohuku region and points south.
Even in cities that lie well outside the earthquake zone, daily life was increasingly becoming disrupted by rolling blackouts and the curtailment of Japan's much-vaunted transit network, both of which will be key to restarting the engine of the world's third-largest economy. Stock prices stabilized Wednesday after tumbling for two days, but there was deepening gloom over the long-term financial outlook in the wake of the worst earthquake in the country's recorded history — a concern even among survivors who have far more immediate and pressing fears.
"I'm worried in the long term about Japan's economy," said Yoshiko Konno, in her 60s, as she charged her cellphone at a community center in Sendai. "Just think of one example — oysters! Are Americans and Europeans going to want to import Japanese oysters if they think there is a danger of radioactive contamination?"
Five days later, the true scale of the disaster is still unknown. At least 10,000 people are feared dead, a tally that is expected to take weeks to finalize. About half a million others have been displaced by quake and tsunami damage or the evacuation triggered by the emergency at Fukushima, a once-obscure nuclear plant that is now the focus of worldwide scrutiny.
The cause of Wednesday's blaze at the Unit 4 reactor — also the scene of a fire the day before — was not immediately known. The plant's operator, Tokyo Electric Power Co., known as Tepco, said radiation levels were too high for firefighters to get close. Later, authorities said the blaze seemed to be subsiding on its own, as the one the previous day did. But hours later, public broadcaster NHK showed breaking aerial footage of a plume of white smoke rising from the reactor.
At the plant, where a small cadre of workers in protective gear remained doggedly on the job, desperate and improvisational measures have become the rule. Tepco said it was considering using a helicopter to douse a boiling storage pool filled with spent fuel rods. The spent rods are usually submerged in the pool next to the Unit 4 reactor, which was not operating when the earthquake and tsunami struck.
But government officials said the helicopter plan had been ruled out as too difficult. Yuichi Sato, a spokesman at Japan's Nuclear and Industrial Safety Agency, said the company was weighing options, including using firetrucks to shoot water into the reactor building.
Tepco has been sharply criticized for its handling of the crisis at the plant, where three of the six reactors have been rocked by explosions caused by overheating in their core containment chambers. The quake and tsunami knocked out power to the cooling systems, triggering a series of breakdowns and missteps that exposed fuel rods to the air at one reactor and released dangerous levels of radiation outside the plant.
The company said an estimated 70% of the fuel rods had been damaged at the Unit 1 reactor and 33% at the Unit 2 reactor. Nuclear safety agency spokesman Shigekatsu Omukai said the utility reported the figures to the agency Wednesday.
Spent fuel at the complex is an increasing focus of concern. Tepco had moved all of the rods from the Unit 4 reactor to the spent-fuel pool sometime after Dec. 1 as part of routine maintenance, meaning the pool contained not only all of the rods accumulated from many years of service but also all of those currently in use.
If the pool was jam-packed with rods, they would generate significant heat and, once the water stopped circulating after the tsunami, its temperature would begin rising, eventually reaching the boiling point. If the water boiled long enough without being replenished, it would expose the rods to the air.
In 2006, the National Academy of Sciences issued a report warning that a loss of cooling water or circulation could trigger a catastrophic fire in a spent-fuel pool that would result in large releases of radioactive material. If the rods become exposed to the air, their zirconium tubes begin to react with oxygen and heat up even more, a type of oxidation fire. At some point, the material inside the tubes melts and can release highly radioactive isotopes such as cesium-137 and iodine-131.
The report was prompted by concern about a potential terrorist attack, but the physics would be exactly the same in the case of a loss of coolant from a natural disaster, said Kevin Crowley, director of the nuclear and radiation studies board at the National Academies, who headed the study. The potential for a worst-case outcome in any kind of incident depends on how closely the rods are packed, the age of the rods, the size of the pool and how much fuel is in the pool, Crowley said.
Source: http://www.latimes.com/
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