Monday, March 14, 2011

Third Explosion Rocks Japanese Nuclear Power Plant

latimes.com/news/nationworld/world/la-fg-japan-quake-20110315,0,2212206.story

latimes.com

Third explosion rocks Japanese nuclear power plant

Officials in Japan acknowledge that the radioactive fuel inside one of the damaged reactors at the crippled Fukushima power plant is in jeopardy of melting down. Meanwhile, the death toll rises.

By Ralph Vartabedian, Laura King and Thomas H. Maugh II, Los Angeles Times
7:53 PM PDT, March 14, 2011
Reporting from Tokyo

Japan's nuclear crisis reached new heights as a third explosion rocked the crippled Fukushima power plant and officials acknowledged that the radioactive fuel inside one of the damaged reactors was in jeopardy of melting down.

The reactor, about 150 miles north of Tokyo, "is not necessarily in a stable condition," Japan's chief Cabinet secretary, Yukio Edano, said at a news conference Tuesday. Prime Minister Naoto Kan called the situation "worrisome."

The explosion followed an acknowledgement from Tokyo Electric Power Co., which owns the plant, that, due to human error, the fuel rods inside the plant's No. 2 reactor had been at least partially exposed to air for more than two hours, allowing them to heat up and causing a buildup of explosive hydrogen gas. Outside experts said it was a grave development that heightened the risk of an uncontrolled release of radiation into the environment.

Meanwhile, about 2,000 bodies were discovered Monday at two sites in Miyagi prefecture, one of several pummeled by the magnitude 9 earthquake and resulting tsunami. The twin disasters wiped whole coastal villages from the map, and survivors faced growing hardship and privation in the quake zone, with tens of thousands of people spending a fourth night in chilly shelters.

A full assessment of the extent of deaths and damage was expected to take weeks. More than half a million people have been displaced, and the death toll is widely expected to soar into the tens of thousands.

The U.S. government mobilized emergency resources to help Japan grapple with the evolving nuclear crisis, dispatching a team of Nuclear Regulatory Commission experts late Monday to Japan, activating an atmospheric radioactivity monitoring center at Lawrence Livermore National Laboratory in the Bay Area and rushing additional Navy ships to region.

In the best-case scenario, the situation at the damaged reactors will take weeks, if not months, to stabilize, U.S. nuclear experts said.

"They do not have the situation under control," said Robert Alvarez, a nuclear expert at the Institute for Policy Studies and a former Energy Department deputy.

The most recent reports that a "suppression pool" at the bottom of the No. 2 reactor, designed to serve as a last line of defense against a meltdown, was breached could represent a major escalation of the crisis, said Victor Gilinsky, a former Nuclear Regulatory Commissioner.

"If that is true, then there is a path to the control room, the workers and the outside environment," he said.

The cooling problems at reactor No. 2 represent the most serious development in the ongoing problems at the nuclear power plant to date, according to nuclear specialist Edwin Lyman of the Union of Concerned Scientists.

When the fuel rods get too hot and react with water, they produce hydrogen gas that vents from the reactor into the containment building. When enough hydrogen accumulates, it becomes explosive. Containment domes around two other reactors at the Fukushima complex had already suffered explosions on Saturday and Monday.

Engineers had begun using fire hoses to pump seawater into the reactor — the third reactor at the Fukushima No. 1 complex to receive the last-ditch treatment — after the plant's emergency cooling system failed. Company officials said workers were not paying sufficient attention to the process, however, and let the pump run out of fuel, allowing the fuel rods to become partially exposed to the air.

Once the pump was restarted and water flow was restored, another worker inadvertently closed a valve that was designed to vent steam from the containment vessel. As pressure built up inside the vessel, the pumps could no longer force water into it and the fuel rods were once more exposed.

The company said it was confident it could reopen the valve and restore water flow, but it has not yet announced that it has done so.

"We are trying to reopen the valve," said one of the four company officials as they passed the microphone back and forth between them at the Tuesday morning news conference. "The fuel rods are exposed. We are trying to get the pressure down and pump water into the pressure vessel again."

The officials began the news conference by bowing and apologizing for the worry caused.

Prime Minister Kan said senior government ministers and Tokyo Electric would set up a joint operation to deal with the nuclear crisis.

In something of a contradiction, officials at Japan's Nuclear and Industrial Safety said that, even in a worst-case scenario, the three troubled reactors at Fukushima No. 1 had been depressurized by the release of radioactive steam, which would decrease the destructiveness of any breach, according to the Kyodo News agency.

But other nuclear experts said it remained possible that an overheated uranium core in any of these reactors could melt down and breach its containment vessel, exposing the environment to a radioactive plume.

The seriousness of the situation was further underscored Monday when the French Embassy in Tokyo advised its citizens to move away from Japan's capital city to protect themselves against possible radiation exposure.

The U.S. Navy's 7th Fleet also said Monday that it had ordered the U.S. aircraft carrier Ronald Reagan away from Fukushima plant after detecting low-level contamination in the air and on its aircraft operating area when it was about 100 miles northeast of the site. It said the contamination was removed easily with "soap and water."

Hundreds of thousands of Japanese civilians have already been evacuated from a 12-mile zone surrounding the plant, and the company said it had moved 50 workers away from the Fukushima plant as well.

In the U.S., the NRC said Monday it had received a formal request from Japan for assistance and was sending 10 people with expertise in boiling water reactors. Agency spokesman Scott Burnell said the experts knew that they might have to "undergo radiation doses larger than normal" to help bring the situation under control.

Another serious risk involves the more than 200 tons of spent nuclear fuel that is stored in pools adjacent to the reactors, Alvarez said. Those cooling pools depend on continually circulating water to keep the fuel rods from catching on fire. Without power to circulate the water, it heats up and potentially boils away, leaving the fuel rods exposed to air.

An aerial photograph of the Fukushima complex shows the loss of high-capacity cranes needed to move equipment to service the reactor. The photo also appears to show that the spent fuel pool is steaming hot, an abnormal condition that may indicate the water is boiling off, Alvarez said.

U.S. nuclear experts said they were particularly concerned about reactor No. 3 because it is fueled in part with plutonium, an element used in hydrogen bombs that can be more difficult to control than the enriched uranium that is normally used to fuel nuclear power plants.

The U.S. Department of Energy activated the National Atmospheric Release Advisory Center at Livermore to create sophisticated computer models of how the radioactive releases from Fukushima would disburse into the atmosphere. The center, which was created to deal with contamination in the event of a nuclear war, played a key role in predicting contamination patterns during the 1986 Chernobyl nuclear crisis.

On Monday, there were signs that the legendary patience and politeness of Japanese in the face of such adversity was wearing thin. A widely held sentiment among disaster victims — and millions more who haven't been directly touched — is resentment at what many feel is the lack of clear, direct information from government officials on the state of the Fukushima nuclear reactors.

But other issues are also fraying nerves.

In Natori, north of Tokyo, the top floor of the City Hall was repurposed into a disaster-relief center. There, in an oft-repeated scene, a woman in red pants and a brown coat berated government workers at the top of her voice for sitting comfortably in their offices with heat, 24-hour power and water while the rest of the prefecture lacked basic services. Voice cracking, she added that the government had been far too slow in restoring the electricity and repairing roads and basic infrastructure.

"She's complaining that our operation doesn't work so well," said Chizuko Nakajima, a government worker in the senior citizen department, who was helping distribute food as an emergency volunteer. "Actually, it's true. We're so overwhelmed, have to do so much and it's not working perfectly. I understand she's angry and wants to direct it somewhere, but I'd rather people didn't do that."

The emergency food handouts are meant for those who've lost their homes. But with power out, most supermarkets, restaurants and convenience stores closed, and gasoline very difficult to acquire, people in undamaged houses are asking for government allocations as well.

Some officials said they saw a sliver of hope that food-related angst might ease soon. More citizens had started donating food on the streets, some making large pots of miso soup for passersby.

Adding to the sense of anxiety, strong aftershocks have rippled across a wide area since Friday's quake. Japan's Meteorological Agency said Saturday there was a 70% probability of another powerful temblor in the coming three days.

ralph.vartabedian@latimes.com
laura.king@latimes.com
thomas.maugh@latimes.com

King reported from Tokyo and Vartabedian and Maugh from Los Angeles.

Times staff writer Mark Magnier in Natori, Japan, and special correspondent Kenji Hall in Tokyo contributed to this report.

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