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7 of 13

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Re: Earthquake in Japan
« Reply #20 on: March 16, 2011, 01:02:25 AM »

before and after satellite images of japanese nuclear reactor



« Last Edit: March 16, 2011, 06:52:35 PM by 7 of 13 »
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Dmitry

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Fukushima: Mark 1 Nuclear Reactor Design Caused GE Scientist To Quit In Protest

Thirty-five years ago, Dale G. Bridenbaugh and two of his colleagues at General Electric resigned from their jobs after becoming increasingly convinced that the nuclear reactor design they were reviewing -- the Mark 1 -- was so flawed it could lead to a devastating accident.

Questions persisted for decades about the ability of the Mark 1 to handle the immense pressures that would result if the reactor lost cooling power, and today that design is being put to the ultimate test in Japan. Five of the six reactors at the Fukushima Daiichi plant, which has been wracked since Friday's earthquake with explosions and radiation leaks, are Mark 1s.

"The problems we identified in 1975 were that, in doing the design of the containment, they did not take into account the dynamic loads that could be experienced with a loss of coolant," Bridenbaugh told ABC News in an interview. "The impact loads the containment would receive by this very rapid release of energy could tear the containment apart and create an uncontrolled release."

The situation on the ground at the Fukushima Daiichi plant is so fluid, and the details of what is unfolding are so murky, that it may be days or even weeks before anyone knows how the Mark 1 containment system performed in the face of a devastating combination of natural disasters.

But the ability of the containment to withstand the events that have cascaded from what nuclear experts call a "station blackout" -- where the loss of power has crippled the reactor's cooling system -- will be a crucial question as policy makers re-examine the safety issues that surround nuclear power, and specifically the continued use of what is now one of the oldest types of nuclear reactors still operating.

GE told ABC News the reactors have "a proven track record of performing reliably and safely for more than 40 years" and "performed as designed," even after the shock of a 9.0 earthquake.

Still, concerns about the Mark 1 design have resurfaced occasionally in the years since Bridenbaugh came forward. In 1986, for instance, Harold Denton, then the director of NRC's Office of Nuclear Reactor Regulation, spoke critically about the design during an industry conference.

"I don't have the same warm feeling about GE containment that I do about the larger dry containments,'' he said, according to a report at the time that was referenced Tuesday in The Washington Post.

"There is a wide spectrum of ability to cope with severe accidents at GE plants,'' Denton said. "And I urge you to think seriously about the ability to cope with such an event if it occurred at your plant.''

http://abcnews.go.com/Blotter/fukushima-mark-nuclear-reactor-design-caused-ge-scientist/story?id=13141287&page=2

7 of 13

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Re: Earthquake in Japan
« Reply #22 on: March 17, 2011, 09:39:42 PM »

TOKYO—Fear about radiation dangers posed by Japan's nuclear crisis spiked as the U.S. instructed its troops and citizens to stay at least 50 miles away from the crippled reactors—establishing a "no-go" zone far wider than the buffer recommended by the Japanese government itself.

Snow Falls, Rescue Continues
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Snow falls Wednesday as rescue workers search a devastated factory area in Sendai, northern Japan.

And in a vivid sign that Japan's leadership is trying to move decisively to take control of the deepening crisis, the nation's military force dispatched two helicopters Thursday morning local time to dump water over the crippled Fukushima Daiichi power complex in hopes of taming its dangerously overheating nuclear facilities. The effort targeted a pool of spent nuclear fuel at reactor No. 3. Defense Minister Toshimi Kitazawa said the water would help cool the spent fuel, lessening the risk of a catastrophic fire, if the water hit its target.

Mr. Kitazawa also said 11 water-cannon trucks were to be deployed at the plant Thursday afternoon in a further effort to cool the overheating waste.

Japan's nuclear regulator also announced that it was working to connect outside power cables to two of the units at the stricken plant, in hopes of restarting their cooling pumps. They hoped to have the cables available by Thursday afternoon.

Restarting the pumps would mark a major advance in the effort to prevent the nuclear disaster from worsening.

Japan's widening government involvement came as international skepticism built up. Late Wednesday, the U.S. State Department authorized the voluntary evacuation of dependents of U.S.-government personnel based in northeast Japan.

Earlier in the day, the top U.S. nuclear regulator, Gregory Jaczko, called radiation levels at one of the plant's units "extremely high," adding that, "for a comparable situation in the United States we would recommend an evacuation for a much larger radius than is currently being provided in Japan."

Previously the U.S. had agreed with Japanese officials that a 12-mile evacuation zone was adequate. The change came after the NRC ran computer-modeling exercises using "the best available information we have" about the damaged reactors along with accumulated knowledge about how systems inside nuclear plants perform under "severe accident conditions," a spokesman with the Nuclear Regulatory Commission said.

Asked why the U.S. set a broader "no-go" zone than did Japan, government spokesmen Yukio Edano said in a press conference that it was understandable to make a more "conservative decision" when trying to ensure the safety of citizens abroad, in a country where it doesn't exert direct control. He reiterated that Japan's government feels it is taking appropriate measures.

Also on Wednesday, the U.K. government advised its citizens in the city of Tokyo, a full 150 miles from the nuclear site, to "consider leaving the area" due to increasing infrastructure problems. The European Union's energy chief, Guenther Oettinger, also declared the Fukushima Daiichi site "effectively out of control." A spokeswoman for Mr. Oettinger later said the commissioner's remarks reflected his own personal views, and weren't based on privileged information.

Stock markets staged large swings, reflecting the depth of anxiety world-wide. "Every investment decision is made through the prism of what is going on in Japan," said Phil Orlando, chief equity strategist at Federated Investors. The Dow Jones Industrial Average closed 2% lower at 11613. Thursday morning, Tokyo shares slid 2.1%.

Late Wednesday, the U.S. Environmental Protection Agency said it was deploying additional radiation monitors out of "an abundance of caution." The EPA already monitors the air for radiation via a national network of approximately 140 stationary and mobile devices. The agency said it sent additional monitors to Alaska and plans to send some to Hawaii.

Officials with the U.S. Nuclear Regulatory Commission and the Energy Department say they don't expect harmful radiation levels to reach the U.S.

 
Japan's nuclear crisis deepened as a fresh fire broke out in a quake-ravaged nuclear complex and expats fled Tokyo over warnings of radiation leaks. WSJ's Mariko Sanchanta and Yumiko Ono discuss.
As part of the government effort to take on a larger role in the crisis management, on Wednesday plant operator Tokyo Electric Power Co., or Tepco, said 20 government officials had moved into the company's offices as part of a joint crisis headquarters.

The government's use of helicopters to dump water on the site was ordered by Economics Minister Banri Kaieda. "The minister considered the situation to be dangerous and judged there was an imminent necessity to issue the order," said a spokesman for the Nuclear and Industrial Safety Agency, which is part of Mr. Kaieda's purview. "After learning that Tepco was not injecting cooling water, he judged it to be very dangerous."

Two helicopters made two trips each, scooping up tons of seawater in a massive bucket and then trying to dump it into a pool used to store waste-fuel at reactor No. 3. An earlier explosion had blown the roof off of the building, exposing the storage pool and making the helicopter mission possible.

Survivors' Stories
View Interactive


Inside the Reactors
View Interactive

Reactor Monitor
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Japan Quake's Effects
View Interactive

See a map of post-earthquake and tsunami events in Japan, Hawaii and the U.S. West Coast.

Before and After Satellite Images Timeline: Past Nuclear Incidents Shaky Ground: Colliding Area Plates Photos: Disastrous Japan Earthquakes Photos: World's Largest Earthquakes More photos and interactive graphics Because of radiation risk, the helicopters had to maintain considerable altitude. A government official said it wasn't yet clear whether the water hit its target.

The race to build an emergency power supply for the crippled plant, combined with details from the early moments of the crisis, highlight new questions about the design and safety record of the facility, which is Japan's oldest.

Common to all nuclear plants is this fundamental design problem: Engineers try to make the equipment impervious to one threat, but that may make it vulnerable to another.

In this case, the Fukushima Daiichi nuclear complex's back-up diesel-powered generators were built below ground level. This bunker-like positioning would protect the generators from an air strike, cyclone or typhoon—but made them more vulnerable to an earthquake-driven tsunami.

When last week's giant waves struck, they immobilized the generators despite being designed to protect against water. The tsunami also apparently washed away the generators' fuel tanks, which were above ground.

"The earthquake and tsunami we had last week both exceeded our engineering assumptions by a long shot," said Tetsuo Ito, head of Kinki University's Atomic Energy Research Institute, near Osaka. "The nuclear industry around the world probably will have to review how we set those assumptions in designing a nuclear power plant."

Another area of scrutiny is the proximity of the plant's six reactors to one another. Damage to one reactor contributed to damage to another, and their proximity hindered a recovery.

Journal Community
This arrangement can be found at other plants, because it can make it easier to move equipment around and helps to keep a smaller work force, said Mr. Ito. But now it looks like a "bad idea," he said. "We need to strike a better balance of operational efficiency and safety."

Terry Pickens, director of nuclear regulatory policy at Xcel Energy Inc. of the U.S., said there is no cookie-cutter reactor of the vintage of the Fukushima units because utilities in those days hired their own engineering firms and architects, and customized the plants' designs. At Xcel's Monticello plant in Minnesota, diesel generators are kept as far apart as possible so that "a natural phenomenon isn't likely to take both of them out," Mr. Pickens said.

The Japanese plant lost power during Friday's earthquake. The three active reactors shut off automatically as designed, but a lack of electricity left workers unable to operate their cooling systems, leading to overheating. Tepco says the tsunami paralyzed all but one backup generator.

Journal Communitydiscuss“ I wouldn't bet against the Japanese, folks. They are human and flawed like the rest of us but if I had to pick a group to tackle a knotty problem like this one, it would be them. They will stabilize that plant. ”
—Stephen Fitzgerald In a weekend briefing, Tepco Managing Director Akio Komori cited the elevation of the backup generators as one potential issue. A Tepco spokesman confirmed the remarks, adding that a full probe will have to wait while workers try to bring the reactors under control.

A spokesman for Japan's Nuclear and Industrial Safety Agency, the nation's nuclear-power regulator, said Fukushima Daiichi's emergency-generator design is "fairly prevalent" at other Japanese plants. The spokesman, Shigekatsu Ohmukai, disputed that the elevation of the generators was a problem. The agency, he said, had concluded that the plant could withstand a certain size of tsunami but "obviously the tsunami caused by Friday's earthquake exceeded our assumptions. That's the problem."

Tepco tested the Fukushima Daiichi plant to withstand an earthquake magnitude of 7.9—a level of seismic activity the power company thought wouldn't be surpassed in the area, according to company documents on its website from 2010. The quake that struck Friday, however, was about 10 times as big as that theoretical maximum.

In the U.S., where there are 23 similar reactors operated by 11 different companies, backup generators typically are housed in bunker-like buildings at ground level. They are designed with watertight fittings that are intended to keep out water from floods or hurricanes.

General Electric Co. designed three of the six reactors for Tepco at the Daiichi complex but it didn't determine the layout of every piece of equipment, a company spokesman said. Some of that was done by architects and engineers hired by Tepco. He added that the main problem was the larger-then-expected tsunami, not the generator placement.

The Daiichi plant was central to a falsified-records scandal a decade ago that led Tepco to briefly shut down all its plants and led to the departure of a number of senior executives. Nuclear experts say that led to a number of disclosures of previously unreported problems at the plant.

—Yuka Hayashi, Miho Inada, Andrew Morse, Tennille Tracy and Nathan Hodge contributed to this article.

http://online.wsj.com/article/SB10001424052748703899704576203850892933990.html?mod=WSJ_WSJ_News_BlogsModule
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Dmitry

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Re: Earthquake in Japan
« Reply #23 on: March 22, 2011, 07:03:50 AM »

Japan Quake Map, 11-22 March, 2011 (maximum speed).avi

Gary910

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Re: Earthquake in Japan
« Reply #24 on: March 24, 2011, 04:04:34 PM »

It is amazing to me that with the devastation in Japan how quickly the news media moves on. It has unfortunately become a side story now. I feel for the people and their misery is now overshadowed by the events in Libya.

The Japanese people are strong and they will recover. The things going on there are terrible and they deserve whatever help they can get.
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nyfan(41)

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Re: Earthquake in Japan
« Reply #25 on: March 24, 2011, 11:13:48 PM »

It is amazing to me that with the devastation in Japan how quickly the news media moves on. It has unfortunately become a side story now. I feel for the people and their misery is now overshadowed by the events in Libya.
The Japanese people are strong and they will recover. The things going on there are terrible and they deserve whatever help they can get.
-
-
what do you base that on?
truthfully i haven't followed the story that closely
i just googled and it said:
death toll is about 10,000 so far
about 15,000 missing
maybe 400,000 displaced
and 240 billion needed to rebuild the country
- but japan is an extremely wealthy nation
-
-
haiti's earthquake death toll was over 200,000
-
the earthquake in pakistan 5 years ago most likely killed over 100,000  - > that one didn't get so much press/sympathy for whatever reason
-
iraqi civilians dead in the iraqi war is over 100,000
-
hurrican katrina death toll was less than 2,000 -> that got alot of coverage though
-
9/11 death toll was less than 3,000
-
the death toll in darfur sudan related to their conflict is over 200,000
-
for that matter,
over 20 million people in africa have aids
-
and so on and foreverforth. it's actually pretty subjective when you notice who 'feels' for who and what gets on the front page when

i really don't understand your comment
when should it be a side story?... next week? never?
and what does 'deserve help' mean?
i'm lost here
sorry, not trying to be an ^$$hole but what do you really expect from the press and why does a japanese person deserve help more than anyone else who suffers? you sound brainwashed



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Gary910

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Re: Earthquake in Japan
« Reply #26 on: March 25, 2011, 01:21:40 AM »

I think you misunderstood what I was saying.

I don't think anyone deserves help above another. I was just commenting that they are still suffering and there is mass devastation and the mainstream press moves on so quickly. I don't really know a good timetable for moving on. I just have a lot of compassion for these people and their suffering.
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nyfan(41)

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Re: Earthquake in Japan
« Reply #27 on: March 25, 2011, 01:54:36 AM »

i hear you
as far as media coverage tho i think they make more money off charlie sheen
real talk
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