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The end of the empire of Japan


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You're missing the point, Chernobyl was an out of control nuclear reaction that resulted in a nuclear explosion. The Japanese reactors have shut down and aren't reacting anymore. The worst that could happen would be an explosion that caused nuclear material to be scattered over the surrounding area. The reports, so far, show that the explosion shown on TV didn't damage the reactor core so no nuclear material was released in the explosion. As we speak they're using sea water to cool the remaining reactors.

Well, that's a good thing, and hope they continue and manage to keep it under control. But I guess now there will be a question of how do you make nuclear plants in quake zones safer.

Yeah but in 2004 they didn't have any warning. People were just at home without any training on tsunamis. Japan is one of the most prepared countries in the world. People would have evacuated those small villages along the coast A) after the quake B ) when they heard the evacuation notice/sirens.

The conditions of the roads were in no shape to evacuate. And there was not much warning with the tsunami because of where ther quake's eppicenter was located. Seems to be located 500 kms off the Japan coast, and the tsumani's can reach up to 800kph. So they could have had less than an hour to get out after the quake hit. That's not a lot of time considering everyone else will be wanting to get out of there as well.

http://www.boston.com/news/source/2011/03/report_9500_mis.html

The death toll in Japan from yesterday's massive, 8.9-magnitude earthquake officially stood at 574 this morning, but the number is expected to climb into the thousands as emergency responders scour some of the hardest-hit areas.

In one town, as many as 9,500 people are missing, reports CNN:

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The reactor of Chernobyl is a Soviet-designed High Power Channel-type Reactor(RBMK). Its structure and design is very different from the Pressurized Water Reactor(PWR)used in North America, Western Europe, China and Japan. The Chernobyl disaster took place because there was a design flaw in the reactor which would make the control rod jammed if the reactor overheated. The operator just could not stop the nuclear chain reaction in the RBMK so the overheated core of the reactor exploded and the explosion destructed the reactor casing which was used to contain the radioactive material of the core.

To a PWR, even if the core of the reactor is overheated, the fuel rods will melt and fall down to the bottom of the casing so the chain reaction will be spontaneously stopped. The explosion in Japan was just because of the hydrogen gas which came from the release valve. The reactor casing is still intact(that's very important). The explosion is totally chemical and outside the reactor casing. Before the explosion, the chain reaction in the core had already stopped and the amount of radioactive material released from the release valve was very small because the reactor casing was still undamaged. The property and consequence of this event are more like the Three Mile Island accident's in the USA, though the Hydrogen released from the reactor didn't exploded in the Three Mile Island accident.

Great, accurate post....safer is smarter when it comes to things nuclear.

Edited by bush_cheney2004
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Great, accurate post....safer is smarter when it comes to things nuclear.

That's the truth, eh? Chernobyl was like a multi-megatonne H-Bomb making a huge chunk of the Ukraine glow in the dark. These Japanese reactors are soooooo much safer.

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Seems like one plant has exploded. Not the cores itself, but part of the plant connected to them.

http://www.businessinsider.com/fukushima-nuclear-plant-2011-3

There was an explosion at the plant at around 3:30 in the afternoon in Japan, and at least 4 are injured. Massive plumes of smoke can be seen.

According to Russia Today, there have been 50K evacuated in the vicinity. Beyond that, the roof of one reactor apparently collapsed.

People in a wide vicinity have been told to cover their mouths as much as possible.

Update 5:10 AM: CNN is reporting that the evacuation zone has been expanded to 20KM around the plant.

Just outside the 20KM radius, notes CNN, is the city of Minamisoma, population 72K.

Update 8:06 AM: Kyodo has a long article explaining the latest, and at this moment there may still be reasons to be hopeful, specifically noting that the explosion is at the plant, near the reactor, but not inside vulnerable reactor #1.

http://www.bbc.co.uk/news/world-asia-pacific-12720219

A huge explosion has rocked a Japanese nuclear power plant damaged by Friday's devastating earthquake.

A pall of smoke was seen coming from the plant at Fukushima. Four workers were injured.

Japanese officials say the container housing the reactor was not damaged and that radiation levels have now fallen.

A huge relief operation is under way after the 8.9-magnitude earthquake and subsequent tsunami, which are thought to have killed at least 1,000 people.

The offshore earthquake triggered a tsunami which wreaked havoc on Japan's north-east coast, sweeping far inland and devastating a number of towns and villages.

I think this was all yesterday though. But wow.

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impassable roads, thousands likely dead, thousands more missing or trapped...a nuclear plant explodes, technicians are struggling to contain a meltdown, cesium has been detected escaping reactor core...long term damage from the reactor situation could be worse than the tsunami and earthquake combined...if the reactor melts down and the region is evacuated is there any hope for those still trapped in the debris?...

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impassable roads, thousands likely dead, thousands more missing or trapped...a nuclear plant explodes, technicians are struggling to contain a meltdown, cesium has been detected escaping reactor core...long term damage from the reactor situation could be worse than the tsunami and earthquake combined...if the reactor melts down and the region is evacuated is there any hope for those still trapped in the debris?...

Scary is it not?

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The U.S. also recovered nicely from the San Fransisco Earthquakes of, I believe, 1906 and 1989 and the Los Angeles Earthquake of, I believe, 1994. Organized societies such as the U.S. and Japan can recover. Disorganized ones such as Haiti, Pakistan and Indonesia, not so readily.

My sister lived in San Francisco in 1989 and on the day of the quake decided to book off from work. The building she worked in collapsed that day.

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http://www.cnn.com/2011/WORLD/asiapcf/03/11/japan.nuclear/index.html?hpt=T1&iref=BN1

Tokyo (CNN) -- Reactors at two Japanese power plants can no longer cool radioactive substances, a government official said Saturday, adding that a small leak had been detected at one of the facilities.

Atomic material has seeped out of one of the Fukushima Daiichi plant's five nuclear reactors, about 160 miles (260 kilometers) north of Tokyo, said Kazuo Kodama, a spokesman for Japan's nuclear regulatory agency.

Potentially dangerous problems in cooling radioactive material appear to have cropped up there, as well as at another of the Tokyo Electric Power Co. nuclear plants, Ichiro Fujisaki, Japan's ambassador to the United States, confirmed to CNN.

The Fukushima Daini and Fukushima Daiichi power plants are separate facilities located in different towns in northeastern Japan's Fukushima prefecture. Each one has its own set of individual nuclear reactors.

Kodama said the cooling system had failed at three of the four such units of the Daini plant.

A horrible situation is going to get worse.

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Scary is it not?

very scary...now all the anti-nuclear people can justifiably come back and say "we told you so"...building nuclear reactors in active fault areas is dumb, dumb, dumb, no matter how well designed there is no way to predict what nature can throw at it...I'm sure the Japanese engineers thought they had considered every scenario in construction but still it wasn't enough...

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very scary...now all the anti-nuclear people can justifiably come back and say "we told you so"...building nuclear reactors in active fault areas is dumb, dumb, dumb, no matter how well designed there is no way to predict what nature can throw at it...I'm sure the Japanese engineers thought they had considered every scenario in construction but still it wasn't enough...

Well no matter how much you prepare, how much you account for, shit still happens. So only when you are in certain situations and the aftemath will you be able to analyze to better prepare.

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http://news.blogs.cnn.com/2011/03/12/japan-earthquake-live-blog-death-toll-rises-amid-widespread-destruction/

[5:48 p.m. ET, 7:48 a.m. Tokyo] A meltdown may be under way at one of Fukushima Daiichi's nuclear power reactors, an official with Japan's nuclear and industrial safety agency told CNN Sunday.

A meltdown is a catastrophic failure of the reactor core, with a potential for widespread radiation release. However, Toshiro Bannai, director of the agency's international affairs office, expressed confidence that efforts to control the crisis would prove successful.

Meanwhile, a second reactor at the same facility failed shortly after 5 a.m. Sunday, the Tokyo Electric Power Company said, according to TV Asahi. The power company said it was having difficulty cooling the reactor and may need to release radioactive steam in order to relieve pressure.

Crap. :(

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very scary...now all the anti-nuclear people can justifiably come back and say "we told you so"...building nuclear reactors in active fault areas is dumb, dumb, dumb, no matter how well designed there is no way to predict what nature can throw at it...I'm sure the Japanese engineers thought they had considered every scenario in construction but still it wasn't enough.
1) There has been no major disaster. There have been only some minor radiation leaks. If a disaster actually occurs then you might have a point. So far the multiple tiers of fail safes have prevented a disaster so lets not get ahead of the facts.

2) The reactors are shutdown. There is zero chance of a Chernobyl type event. The worst case scenario is a large radiation release which would be bad but not the end of the world (certainly less harmful that the Gulf of Mexico blowout).

3) Japan has no sources of fossil fuels within the country. This means they will build nukes no matter what the earthquake risk because they cannot risk being totally dependent on foreign suppliers for their energy needs.

Edited by TimG
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FWIW:

These reactors had three coolent systems that have failed:

1) The main coolent system when offline when local eletricity grid went down;

2) The diesel generator backup failed because of water damage from the tsunami;

3) The emergency battery backup system failed after 8 hours when the batteries ran down.

It appears that the combination of earthquake and tsunami is what created the problem. Although it is not clear to me why the diesel generators were even in a position to be affected by a tsunami. Nor is it clear why they have not been able to fly in replacement generators.

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3) Japan has no sources of fossil fuels within the country. This means they will build nukes no matter what the earthquake risk because they cannot risk being totally dependent on foreign suppliers for their energy needs.

Maybe Japan and other similarly situated countries should have been less politically correct about "producing" nations' seizure of private oil companies?
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FWIW:

These reactors had three coolent systems that have failed:

1) The main coolent system when offline when local eletricity grid went down;

2) The diesel generator backup failed because of water damage from the tsunami;

3) The emergency battery backup system failed after 8 hours when the batteries ran down.

It appears that the combination of earthquake and tsunami is what created the problem. Although it is not clear to me why the diesel generators were even in a position to be affected by a tsunami. Nor is it clear why they have not been able to fly in replacement generators.

Would it even be possible to get the generators hooked up and integrated in time to prevent a catastrophe? That's a huge job. Not sure if you can just get them on a moments notice, because you'd need some very powerful generators, and the fuel to run them. I also think it would be a problem of getting them in the right spot to be effective. Must be debris everywhere.

The size of these generators needed would be the size of semi-trucks, or shipping containers.

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1) There has been no major disaster. There have been only some minor radiation leaks. If a disaster actually occurs then you might have a point. So far the multiple tiers of fail safes have prevented a disaster so lets not get ahead of the facts.

Time is ticking.

http://www.cnn.com/2011/WORLD/asiapcf/03/12/japan.quake.nuclear.failure/index.html?hpt=T1&iref=BN1

Tokyo (CNN) -- A meltdown may be under way at one of Fukushima Daiichi's nuclear power reactors in northern Japan, an official with Japan's Nuclear and Industrial Safety Agency told CNN Sunday.

"There is a possibility, we see the possibility of a meltdown," said Toshihiro Bannai, director of the agency's international affairs office, in a telephone interview from the agency's headquarters in Tokyo. "At this point, we have still not confirmed that there is an actual meltdown, but there is a possibility."

A meltdown is a catastrophic failure of the reactor core, with a potential for widespread radiation release.

Though Bannai said engineers have been unable to get close enough to the core to know what's going on, he based his conclusion on the fact that they measured radioactive isotopes in the air Saturday night.

Also quakes are still going on in the area.

http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_all.php

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That's the truth, eh? Chernobyl was like a multi-megatonne H-Bomb making a huge chunk of the Ukraine glow in the dark.

The uranium fuel in a reactor isn't weapons-grade so the chain reaction may not fast enough to make it a A-bomb, but the Chernobyl reactor's hull was damaged because the design of the reactor lacked self-stopping mechanism. The power generated by the uncontrolled chain reaction was so massive that the 2,000 ton upper plate of the reactor's concrete hull was reportedly blasted off and the radioactive material from the core of the reactor was ejected from the broken hull and scattered everywhere which caused the disaster. It worked more like a huge dirty bomb than a A-bomb.

Edited by xul
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OK...but technically, this is not a failure of the battery backup system. Where I work, we do not expect the UPS to provide power indefinitely.
But you need to design the battery backup system to last long enough to get the main power back on. In this case, 8 hours was not enough so you could consider it a design failure for the battery backup system. That said, we are probably spliting hairs on this point.
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Seems to me the biggest problem here was the reactor being located in a tsunami zone, not an earthquake zone.
It appears that way but that does not make a lot of sense since elevation rises pretty quickly as you move away for the coast and there should have been no need to build a plant in a tsunami zone. I don't know if a 10m tsunami was beyond what anyone had previously anticipated. I do know that they have signs posted everywhere near a coastline that was in an expected tsunami zone. These are one of the details that the inquiry will have to sort out.

Maybe they built near the coastline because it would give them access to seawater which is currently being used to cool the reactors.

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