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Earthquake/tsunami in Tohoku, North East Japan (11th March 2011)


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The Times

 

What has happened to the Fukushima Daiichi nuclear reactors?

 

Three of the plant’s six reactors were running at the time of the earthquake and were immediately shut down. Control rods were inserted into the core to stop nuclear fission.

 

Even after shutdown, a reactor will remain hot because of residual radioactive decay in its fuel rods. So water must be pumped in to cover these rods and cool them.

 

Grid electricity for these pumps failed, and an hour later back-up diesel generators were swamped by the tsunami. Battery power was insufficient to cool all the reactors fully, causing reactor 1 to overheat. Reactor 3 later overheated as well, reportedly because of a water injection failure.

 

What are the consequences of overheating?

 

Much of the water covering the fuel rods turns to steam, exposing more of the rods and raising temperatures further. The steam also increases pressure within the reactor vessel. If this increases too much, rupture is possible. Rising temperatures can also cause meltdown.

 

What is meltdown and does it matter?

 

It occurs when the zirconium alloy casings of fuel rods melt, exposing the uranium or plutonium fuel and radioactive by-products such as caesium-137. This radioactive material can then mix with steam, so that if there is an explosion it can be released to the atmosphere.

 

Melting fuel rods also clog the bottom of the core, but this is more of an issue for clean-up than public safety. It is technically possible for molten fuel to melt the containment vessels around the core, but it is extremely unlikely.

 

A meltdown does not mean there will inevitably be an explosion or major radiation release. Reactors are designed to contain meltdowns.

 

Are the reactors in meltdown?

 

The Japanese authorities have given conflicting statements. As caesium-137 has been detected outside reactor 1, a partial meltdown is possible. The situation in reactor 3 is uncertain.

 

What is being done about it?

 

Steam has been deliberately vented from the containment vessels to lower pressure. Low levels of radioactive isotopes are present in this steam, but it does not present a serious health risk. Evacuations are precautionary.

 

Seawater has been pumped in to cool the reactors, together with boric acid which catches neutrons and reduces heat from residual decay. The methods are untested, but nuclear engineers believe they should work.

 

What was the explosion on Saturday?

 

In overheated reactors, water can react with zirconium to produce hydrogen. Once vented from the containment chamber, this ignited to cause the explosion. Though dramatic, it did not damage the containment chamber. The outer walls that were destroyed were nothing more than a weatherproof shell, and are not involved in containing the reactor core.

 

How does this compare with other nuclear accidents?

 

It is most similar to the Three Mile Island disaster of 1979, though less serious. Fukushima is rated at 4 on the International Atomic Energy Agency’s 7-point scale, while Three Mile Island was rated 5. Three Mile Island involved a partial core meltdown, which was fully contained with little radiation release.

 

Is a Chernobyl-type disaster possible?

 

No. The circumstances of Chernobyl (a level-7 disaster) were fundamentally different. A botched safety test while the reactor was running caused a surge of pressure, explosions and a fire. This was worsened because the reactor lacked adequate containment — its design would not have been permitted outside the Soviet Union — so a plume of radioactive debris was thrown into the atmosphere.

 

Will there be a nuclear explosion?

 

No. Nuclear reactors cannot produce these. Even Chernobyl was the result of pressure and chemical explosions that threw out radioactive material: more similar to a “dirty bomb†than an atomic bomb.

 

What are the risks to public health?

 

So long as the containment vessels around the core remain intact, there will be minimal risk.

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More please!   http://www.youtube.com/watch?v=0HrO2H4Sraw   You'd think they might put in some of the overly loud throat noises and he would do a big "ahhhhhhhhhh" at the end. Come on, where's th

Originally Posted By: grungy-gonads
Very very pretty newsreader watch:

Lordy dordy. kiss
A real classy cutie!
From the local Sendai news just now, being shown on the national channel

friend

Just trying to cheer myself up.


We need pics!
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Originally Posted By: BagOfCrisps
Originally Posted By: grungy-gonads
Very very pretty newsreader watch:

Lordy dordy. kiss
A real classy cutie!
From the local Sendai news just now, being shown on the national channel

friend

Just trying to cheer myself up.


We need pics!


We need VIDEO! wink
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To anyone in Niseko:

 

We are trying to rally some troops in the coming week. Once we figure out where help is needed a few of us are planning to offer our assitance wherever it will best be utilized. If anyone in the Niseko area is interested please say so and I will let you know what we are doing.

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Originally Posted By: RobBright
Originally Posted By: grungy-gonads
I wish I had it.

She was so lovely, just my タイプ

evilgrin


A plumper then? wink


No.... pretty, elegant, feminine, intelligent looking beauty

thumbsup
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Mitchpee, you would just be turned away.

One of my friends in tokyo is in contact with the said organisations and all non-essential people are being turned away.

Volunteers are needed and once announced where and when, I will pass the information on to sjd.

 

All you would do right now is take up resources that the survivors need.

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I'm gonna go through all my clothes tonight & give what I dont need. Also gonna give away all the old baby clothes that dont fit my daughter. It sucks I cant be up there helping find people, instead I'm doing crappy work at my job.

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Originally Posted By: RobBright
Mitchpee, you would just be turned away.
One of my friends in tokyo is in contact with the said organisations and all non-essential people are being turned away.
Volunteers are needed and once announced where and when, I will pass the information on to sjd.

All you would do right now is take up resources that the survivors need.


If you re-read and thought about what I posted you would come to the conclusion that I said we were WAITING for when needed. Nowhere did I say I was hopping in the car right now and driving there. Just trying to see who may be interested to take a bit of action in helping out.

I cannot believe you would carry over your typical derogatory attitude in such a significant thread. If you want nothing to do with what I am proposing then simply decline. Do not belittle my proposition and make assumptions about what I am doing.

With that said, if anyone in the Niseko area is interested in helping out I would be glad to keep a name and update if we develop some course of action to take.
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Originally Posted By: norcal
I'm gonna go through all my clothes tonight & give what I dont need. Also gonna give away all the old baby clothes that dont fit my daughter. It sucks I cant be up there helping find people, instead I'm doing crappy work at my job.


We've already got a few boxes full of clothes, blankets, etc but not sure where we can send them. We thought the defence base here was accepting stuff like this but we rang and they advised they aren't able to as they can't get it down to the affected areas. Anyone know where we can send such things?
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Originally Posted By: Go Native
Originally Posted By: norcal
I'm gonna go through all my clothes tonight & give what I dont need. Also gonna give away all the old baby clothes that dont fit my daughter. It sucks I cant be up there helping find people, instead I'm doing crappy work at my job.


We've already got a few boxes full of clothes, blankets, etc but not sure where we can send them. We thought the defence base here was accepting stuff like this but we rang and they advised they aren't able to as they can't get it down to the affected areas. Anyone know where we can send such things?


ran into this gem from a couple of Japanese friends

Here's how you can help with the earthquake relief efforts.

---

You can send items to these addresses through your local neighborhood Japanese Post Office:

They really need :

1. Foods (instant foods, dietary supplements, baby foods)
2. Warm blankets (That north part of Japan is still really cold now)
3. Cothing
4. Baby clothings, and DIAPERS!!!!


Attn: Earthquake relief supplies
Miyagi Prefectural Office
3-8-1, Honcho
Aoba-ku, Sendai city, Miyagi
980-8570, JAPAN

Attn: Earthquake relief supplies
Iwate Prefectural Office
10-1 Uchimaru Morioka city, Iwate
020-8570,JAPAN

Attn:Earthquake relief supplies
Aomori Prefectural Office
1-1-1 Nagashima, Aomori city,
Aomori, 030-8570, JAPAN

Attn:earthquake relief supplies
Fukushima Prefectural Office
2-16 Sugitsuma-cho, Fukushima City
960-8670, JAPAN
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Originally Posted By: muikabochi
I have just watched the recorded thing on the BBC site now.
It is ridiculous.
Some of the coverage and misinformation being said is starting to anger me.


Me too. I saw on an Aus media outlet they reported a 'nuclear' explosion at the number 3 reactor. Utterly ridiculous fear mongering. But that's western media for you these days.
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CNN just told me this:

 

Breaking news of a 6.0 Mag earthquake in NAGANO.

Sketchy details.

'You might remember Nagano from the Olympics a while back'.

 

Well, Japan news and earthquake info sources ain't reporting that.

 

WTF.

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Originally Posted By: muikabochi
CNN just told me this:

Breaking news of a 6.0 Mag earthquake in NAGANO.
Sketchy details.
'You might remember Nagano from the Olympics a while back'.

Well, Japan news and earthquake info sources ain't reporting that.

WTF.


Ratings must be starting to go down so they're just resorting to making stuff up? wink
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There have been a few smaller shakes since the one on Saturday morning.

But even that strongest one wasn't 6.

Bloody annoying.

 

I think I'm going to stop watching much news on all this lot, my state of mind will keep much better.

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There's a woman on CNN now explaining the "breaking news" of the Nagano Mag 6 quake. Seems they are talking about the one at 4am on Saturday morning two and a half days ago. (Which was mag 5.6).

 

wakaranai

 

OK, turning it off.

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