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G0ldfinger

Fukushima I: four reactors in trouble.

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So:

 

You build a massive amount of nuclear power plants in an area where earthquakes happen all the time.

 

You build them on the coast, of course, since you need cooling water.

 

But, obviously, the quakes regularly cause tsunamis (a Japanese word, after all).

 

Now, you would think, with such a predictable calamity being planned, they would shut down all nuclear plants immediately when a quake of a certain strength occurs?

 

I've done a bit of reading on the shutdown processes. There doesn't seem to be an on/off switch.

 

In a reactor an absorbing material (control rod) is used to control the rate of reaction in regular operation. In a simplistic way, push the absorbing material further into the reacting material and the rate of reaction slows as the absorbing material stops some of the sub-atomic particles from colliding, retract the absorbing material and the rate of reaction increases as more particles collide.

 

To shutdown you extend the absorbing material fully into the reacting material, this can happen in seconds, less than a second if you never intend to retract the absorbing material again. While the absorbing material can slow the rate of reaction, it cannot immediately stop it, so the reactor core will continue to generate heat for a while (I can't find out how long) and remain hot for a while longer, I think this is a couple of days with the normal rate of cooling water heat removal.

 

In a normal or emergency shutdown you would plan to keep the cooling water circulating for 2/3(?) days to continue to cool the core down until it reaches atmospheric temperature. The problem in Japan appears to have been with the cooling water pumping systems, primary grid power was lost, site generated power was lost and the backup generators failed sometome after. So you have static water sat next to the core that boils, becomes steam and then starts to build pressure in the sealed reactor chamber. You can vent this pressure from the reactor chamber to the sealed building, but eventually the building also needs to be vented to release pressure in there. If you keep heating the steam (H2O) it can seperate to it's constituent Hydrogen and Oxygen and this appears to have been the cause of the explosion.

 

The water/steam is unlikely to be carrying any particulary nasty levels of radiation in normal operation as it should be shielded from it by a high temperature metal jacket around the core, just picking up the heat and a bit of residual radiation. Venting to atmosphere is not ideal, but if the steam quickly dilutes in the atmosphere it is not terrible. The problem occurs if the high temperature metal jacket fails around the core (meltdown) and the reaction materials and by-products mix into the cooling system, that stuff you can't vent to atmosphere without serious problems.

 

Conflicting reports at the moment about if reaction material or by-products have been detected outside the building which would indicate that part of the metal jacket had failed and the cooling system become contaminated.

 

From what I can tell they're flooding the reactors with seawater and an absorbing material to supplement the control rods, these specific reactors will never work again.

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They should just go to full Meltdown procedures asap imo. If everything is ok then they can all go back to their homes, no? 160 local people are stuffed with radiation, in a TEN PERCENT random test.

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It seems that the news media is preparing us for an announcement that Reactor 1 is in meltdown and I fully expect the authorities to confirm this within the next 24 hours.

 

So what would be the worse case scenario if this is true? Is it possible that Northern Japan (including Tokyo) could become uninhabitable? Doesn't bear thinking about..

 

Comparing Fukushima with Chernobyl this Telegraph article neatly sums things up...

 

Official nuclear safety authorities warned that the plant, about 160 miles northeast of Tokyo, "may be experiencing a nuclear meltdown." Blanket evacuation orders were issued for thousands of residents within first a six, and then a twelve, mile radius. Iodine tablets, antidotes to radiation, were distributed in the local area and beyond.

 

and..

 

"A Chernobyl-type leak here would be far worse than in Russia," said Lee Uranaka, a passer-by in Tokyo's Ginza shopping and nightlife district. "That was a relatively-lightly populated area. There are 30 million people in range of this nuclear power station."

 

http://www.telegraph.co.uk/news/worldnews/asia/japan/8378573/Japan-earthquake-fear-of-worse-nuclear-power-plant-accident-puts-Tokyo-under-a-cloud.html

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"A Chernobyl-type leak here would be far worse than in Russia," said Lee Uranaka, a passer-by in Tokyo's Ginza shopping and nightlife district. "That was a relatively-lightly populated area. There are 30 million people in range of this nuclear power station."

 

http://www.telegraph.co.uk/news/worldnews/asia/japan/8378573/Japan-earthquake-fear-of-worse-nuclear-power-plant-accident-puts-Tokyo-under-a-cloud.html

 

Nice of the telegraph to give such a dire warning from someone who is technically 'a girl who just walked past'. Very professional. Next they'll be quoting twitter. :blink:

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It seems that the news media is preparing us for an announcement that Reactor 1 is in meltdown and I fully expect the authorities to confirm this within the next 24 hours.

 

So what would be the worse case scenario if this is true? Is it possible that Northern Japan (including Tokyo) could become uninhabitable? Doesn't bear thinking about..

 

 

 

I think a lot of the populated areas on the NE coast will be uninhabitable as before anyway. Is there any point rebuilding them anyway, I wonder? Some of the coast line has sunk up to 4 meters. As the plate continues its journey under the other one, this is only going to continue. Better to relocate inland and write the whole area off. Besides these areas were half-dead to begin with, and bitterly cold. Meanwhile...

 

''The disaster forced the Bank of Japan (BoJ) to issue a statement, as it draws up plans for an emergency “quake budget”. The BoJ said: “The bank will continue to do its utmost, including the provision of liquidity, to ensure stability in financial markets and to secure the smooth settlement of funds, in the coming week.”

 

Naoto Kan, the Japanese prime minister, asked BoJ to “save the country” after politicians from both sides of the political spectrum agreed on the need for the budget to introduce emergency spending to fund rescue and clean-up efforts and to resuscitate the economy.''

 

At least the forthcoming financial implosion can be blamed on the Tsunami.

 

If we are looking at the worst scenario re the nuclear plants what would the dead zone radius be? Anyone know? I am way down in the south but we could be accommodating our Tokyo relatives sometime soon.

 

This wasn't quite the 'die-off' I was expecting.

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If we are looking at the worst scenario re the nuclear plants what would the dead zone radius be? Anyone know? I am way down in the south but we could be accommodating our Tokyo relatives sometime soon.

 

 

my advice: watch the wind AND avoid rain. Hopefully a containment vessel breach will not happen; that's what you've got to be watching for I think.

It seems that at some point the fuel rods DID begin to melt in Daiichi-1 because there was Caesium-137 in the steam. That can only really happen if the fuel rod casing has been damaged by melting from the fuel inside (which must have been uncovered by water for a while).

So, assuming the contaiment vessel is intact, then the authorities cannot know how badly the rods have deformed but they do seem to be saying the containment vessel has not been breached yet - so let's hope for the best.

 

As of Sunday morning, winds in northeast Japan were blowing out to sea at 5-15 mph, said CNN Meteorologist Taylor Ward. But they were expected to reverse direction by Monday night, he said. The Daiichi plant is located about 160 miles (260 kilometers) north of Tokyo.

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I read that reactor 3 might have had a partial meltdown already too (reactor 1 is what everyone is talking about).

 

If things turn out lucky for everyone, the core structures hold (on top of the reactors), and they just sink into the ground. That way at least air contamination and fallout would be fairly contained. First nuclear double meltdown ever (maybe more to come yet?) which will stay fairly contained? You can only hope.

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They think that reactor building 3 could blow soon too, with the hope again, that as in the case of reactor 1, the inner structures stay fairly in place.

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I read that reactor 3 might have had a partial meltdown already too (reactor 1 is what everyone is talking about).

 

If things turn out lucky for everyone, the core structures hold (on top of the reactors), and they just sink into the ground. That way at least air contamination and fallout would be fairly contained. First nuclear double meltdown ever (maybe more to come yet?) which will stay fairly contained? You can only hope.

 

Seems like it will be contained to Japan.

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Seems like it will be contained to Japan.

Or on the other hand the west coast of America may take it on the chin courtesy of the jet stream.

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Or on the other hand the west coast of America may take it on the chin courtesy of the jet stream.

 

At this stage there is no mechanism to transport large amounts of solid material in the core

into the air for that to happen.

 

In Chernobyl the moderator was graphite which burnt so that the fire created that mechanism

 

As far was we know at this point in time you have those cores in Japan that get hot but do not

burn and the release of radioactivity will be sufficiently slow that it will be diluted by the massive volume of the atmosphere.

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At this stage there is no mechanism to transport large amounts of solid material in the core

into the air for that to happen.

 

In Chernobyl the moderator was graphite which burnt so that the fire created that mechanism

 

As far was we know at this point in time you have those cores in Japan that get hot but do not

burn and the release of radioactivity will be sufficiently slow that it will be diluted by the massive volume of the atmosphere.

they've got a mechanism to transport the radio active solid material in to the sea. Their going to create there own GODZILLA if there not careful.

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I read that reactor 3 might have had a partial meltdown already too (reactor 1 is what everyone is talking about).

 

If things turn out lucky for everyone, the core structures hold (on top of the reactors), and they just sink into the ground. That way at least air contamination and fallout would be fairly contained. First nuclear double meltdown ever (maybe more to come yet?) which will stay fairly contained? You can only hope.

 

When Chernobyl went up, I remember one of the biggest fears was a melt through with the core sinking into the earth and making the whole of Europe's ground water supply radioactive. Does anyone know if the Japanese use ground water for drinking (wells etc)?

 

 

 

On a lighter note (I hope you don't find this inappropriate), as for Godzilla, I think the Japanese already own him. It might be the Americans who have to get their own.

http://www.youtube.com/watch?v=IEJm0uIVwUc

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I don't know how easy it is to contaminate ground water, and on what scale.

 

The shale gas/oil people in the US seem to happily drill away, despite films like "Gasland" that show how devastating technologies like hyrdofracking can be.

 

I also don't know how ground water reservoirs behave that close to the coast. Maybe they drain towards the ocean? I simply don't know.

 

My guess would be that the core would not get too far, because how hot can it get? It would hit some rock or clay and get stuck.

 

When Chernobyl went up, I remember one of the biggest fears was a melt through with the core sinking into the earth and making the whole of Europe's ground water supply radioactive.

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Link

 

Stoneleigh:

 

How Black is the Japanese Nuclear Swan?

 

...

 

The risk in Japan is primarily meltdown, not a Chernobyl-style run-away nuclear reaction.

 

About the only bit of good news is to say that it is unlikely to be as bad as Chernobyl.

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About the only bit of good news is to say that it is unlikely to be as bad as Chernobyl.

 

From your link:

Comparisons are being made with the accident at Chernobyl, but there are a number of very important differences, notably in terms of reactor design, and therefore accident implications. Nuclear safety in the former Soviet Union was once my research field (see Nuclear Safety and International Governance: Russia and Eastern Europe), and the specifics of the accident at Chernobyl could not be replicated in Japan. The risk in Japan is primarily meltdown, not a Chernobyl-style run-away nuclear reaction.

 

Lets see what a Japanese nuclear power plant designer says:

 

A former nuclear power plant designer has said Japan is facing an extremely grave crisis and called on the government to release more information, which he said was being suppressed. Masashi Goto told a news conference in Tokyo that one of the reactors at the Fukushima-Daiichi plant was “highly unstable”, and that if there was a meltdown the “consequences would be tremendous”. He said such an event might be very likely indeed. So far, the government has said a meltdown would not lead to a sizeable leak of radioactive materials. Mr Goto said the reactors at the Fukushima-Daiichi nuclear plant were suffering pressure build-ups way beyond that for which they were designed. There was a severe risk of an explosion, with radioactive material being strewn over a very wide area – beyond the 20km evacuation zone set up by the authorities – he added. Mr Goto calculated that because Reactor No 3 at Fukushima-Daiichi – where pressure is rising and there is a risk of an explosion – used a type of fuel known as Mox, a mixture of p lutonium oxide and uranium oxide, the radioactive fallout from any meltdown might be twice as bad. He described the worst-case scenario: “It is difficult to say, but that would be a core meltdown. If the rods fall and mix with water, the result would be an explosion of solid material like a volcano spreading radioactive material. Steam or a hydrogen explosion caused by the mix would spread radioactive waste more than 50km. Also, this would be multiplied. There are many reactors in the area so there would be many Chernobyls.” He accused the government of deliberately withholding vital information that would allow outside experts help solve the problems. “For example, there has not been enough information about the hydrogen being vented. We don’t know how much was vented and how radioactive it was.” He also described the use of sea water to cool the cores of the reactors at Fukushima-Daiichi as highly unusual and dangerous.

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From your link:

 

Lets see what a Japanese nuclear power plant designer says:

 

With 30 million people in a 100 mile radius this doesn't look good, does it?

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On a lighter note (I hope you don't find this inappropriate), as for Godzilla, I think the Japanese already own him. It might be the Americans who have to get their own.

http://www.youtube.com/watch?v=IEJm0uIVwUc

This music fits the present situation:

http://www.youtube.com/watch?v=ceUuUfTlB-s

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Fallout map - suggestion was made on the expansions.com website to buy iodine or potassium iodide

if you happen to live in the zone indicated. Don't take any until there is a need to take it

 

<script src='http://img263.imageshack.us/shareable/?i=falloutmap.jpg&p=tl' type='text/javascript'></script><noscript>falloutmap.jpg</noscript>

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BBC reporting that reactor 3 has now blown

 

<edit>

 

Footage of the explosion now being shown on the TV and has been put down to another hydrogen explosion.

 

Compared with the first one, that looked like a very different type of explosion to me

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Nice of the telegraph to give such a dire warning from someone who is technically 'a girl who just walked past'. Very professional. Next they'll be quoting twitter. :blink:

 

:D

 

Very true but the point made was a good one

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Japan quake: Explosion at Fukushima nuclear plant

 

A second explosion has hit the nuclear plant in Japan which was damaged in Friday's earthquake, but officials said it had resisted the blast.

 

TV footage showed smoke rising from Fukushima plant's reactor 3, a day after an explosion hit reactor 1.

 

Japan's nuclear safety agency said the blast was believed to have been caused by the build-up of hydrogen.

 

However, the agency said it could not confirm whether there had been an uncontrolled leak of radioactivity.

 

http://www.bbc.co.uk/news/world-asia-pacific-12729138

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With 30 million people in a 100 mile radius this doesn't look good, does it?

DOUBLE POST

 

Fukushima 3 (the nasty one) blew this morning. So far 11 injured at the site, including members of the SDF. (what were they doing at the plant??) Gov line is same as before. The housing has blown and the concrete container jobbie is ok. The wind has changed direction and is now blowing directly Tokyo's way and the gov say to Tokyo stay at home, no school, no work, no sushi lunches nor karaoke. Are they using the very well known Japanese art of non verbal communication in telling 30 million Tokyoites the shit is blowing their way, take cover? I wonder if the Emperor has relocated elsewhere?

 

Nail biting time here and much oohing and ahhing on TV.

 

In Kyushu Shinmoedake volcano has kicked back into action and erupted for good measure. Is this how Japan ends? Is this the black swan? Many banks and ATM's are out of action (I took out all my cash on Friday, just as a precaution-phew)It wouldn't take long to shut this whole place down if the worst case becomes a reality...THEN there would be panic. But for now, all eyes on Fukushima 3 and the wind.

 

 

At a predawn press conference, Chief Cabinet Secretary Yukio Edano again called on the nation to reduce electricity use. He warned that confusion is expected as the step had to be taken at short notice and a very large number of people will be affected.

 

"Maximum efforts by the nation are indispensable, such as avoiding going out unless it is necessary or urgent," he said.

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