Japan Fukushima nuclear thread

[Globs]

hairykrishna said:

qureshia said:

..... Ambassador Murata writes to UN Secretary General: “It is no exaggeration to say that the fate of Japan and the whole world depends on No. 4 reactor”

I'd say that was in fact a massive exaggeration

I think the issue is that there is far more fuel there than is usually inside a reactor, it's too 'hot' for anyone to get near unless shielded by metres of water, there is no crane available to put up the bits either, and each bit is hundreds of tons of huge, dangerous rod that will be smoking and melting at the time. Effectively you have a multiple meltdown outside of containment.

At least #3 blew it's fuel pool to smithereens around the general area which separated the fuel from becoming a molten mass, but I am puzzled as to what would save #4 being a much bigger disaster than we have seen so far.

So Hairy - how would they deal with an earthquake that smashed #4 pool and let it collapse and all the water escape?

[hairykrishna]

I have no idea. I'm not even saying that there's not potential for larger releases than we've seen so far. I was just commenting that saying 'the fate of the world' is hanging in the balance was a massive exaggeration.

I haven't looked at a list of the inventory of the pond but I doubt each bit is 'hundreds of tons'. Typically a 1000 MW reactor produces a total of ~30 tons of spent fuel a year so I can see the total inventory being 100's of tons. Each fuel bundle's likely to weigh in the 100's of kg range.

Edited by hairykrishna on Sunday 8th April 16:02

[Mojocvh]

"I have no idea"


Just because the common public perception of a nuclear accident lies close to this



quick and short lived event.


The potential radiation release over some 5 decades is simply staggering, but it's a quiet, silent killer that people won't notice until it's too late.

[hairykrishna]

Mojocvh said:

The potential radiation release over some 5 decades is simply staggering, but it's a quiet, silent killer that people won't notice until it's too late.

So what is the potential release? Expected mobility? Expected consequences?

Do you agree with the statement that the fate of Japan and the whole world depends on what happens there?

[Globs]

Governments are responding though, they are busy raising the safe radiation levels to protect us.

http://www.washingtonsblog.com/2012/03/california-...

I would criticise them for this but TBH, that's the only thing they really have any control over...

[Welshbeef]

5 decads of radiation release which would be 85 multiplies the strength of Chernobl which lasted what 2 weeks max.

That is something I cannot get my head around. It's a game changer for sure and would take the worlds third super power out of the game overnight..... Surely the radiation fallout to USA Canada and China would wipe out potentially 4 superpowers from the G7 into the wilderness. There would be no recovery for 70 years and then some.

[Mojocvh]

hairykrishna said:

Mojocvh said:

The potential radiation release over some 5 decades is simply staggering, but it's a quiet, silent killer that people won't notice until it's too late.

So what is the potential release? Expected mobility? Expected consequences?

Do you agree with the statement that the fate of Japan and the whole world depends on what happens there?

Wiser council than ours may think so.....

[hairykrishna]

Mojocvh said:

hairykrishna said:

Mojocvh said:

The potential radiation release over some 5 decades is simply staggering, but it's a quiet, silent killer that people won't notice until it's too late.

So what is the potential release? Expected mobility? Expected consequences?

Do you agree with the statement that the fate of Japan and the whole world depends on what happens there?

Wiser council than ours may think so.....

They may. Based on my own knowledge I think that statement's bks. You?

[Mojocvh]

hairykrishna said:

Mojocvh said:

hairykrishna said:

Mojocvh said:

The potential radiation release over some 5 decades is simply staggering, but it's a quiet, silent killer that people won't notice until it's too late.

So what is the potential release? Expected mobility? Expected consequences?

Do you agree with the statement that the fate of Japan and the whole world depends on what happens there?

Wiser council than ours may think so.....

They may. Based on my own knowledge I think that statement's bks. You?

Well, I hope that you are proven right.

[llewop]

hairykrishna said:

I have no idea. I'm not even saying that there's not potential for larger releases than we've seen so far. I was just commenting that saying 'the fate of the world' is hanging in the balance was a massive exaggeration.

I haven't looked at a list of the inventory of the pond but I doubt each bit is 'hundreds of tons'. Typically a 1000 MW reactor produces a total of ~30 tons of spent fuel a year so I can see the total inventory being 100's of tons. Each fuel bundle's likely to weigh in the 100's of kg range.

Edited by hairykrishna on Sunday 8th April 16:02

factors to consider are beyond just inventory - the initiating event and progression will affect dispersal - what made Chernobyl spread round the globe so effectively was the massive explosion and subsequent fire in the remains of the building from an active reactor - so a lot of energy driving the contamination into upper airsteams and allowing it to disperse. Even a total drain of a pond and subsequent fire from overheating fuel elements is not going to generate anything near the same amount of energy to release and disperse the material.

[qureshia]

For now the statement was made by an Ambassador ...
If memory serves me right they have a habit of talking things up/down as it serves their political whim

It will be interesting to see if the scientific community echo his comments.

[dudleybloke]

If the fuel pools are dry would adding water risk a steam explision?

It seems like its long past time for japan to try and fix this themselves.

[Talksteer]

dudleybloke said:

If the fuel pools are dry would adding water risk a steam explision?

It seems like its long past time for japan to try and fix this themselves.

Adding water to a fuel pool which had boiled dry would generate steam at the same rate as you added water. Given the geometry of the pool I would be surprised if significant pressure would build.

Were you have a completely exposed boil dry of the fuel I would be surprised if BWR fuel melting would have the same mobility as burning spent fuel in the middle of a carbon fire which was the result of Chernobyl. As a result I doubt that the spent fuel pool at reactor 4 would be able to release the same amount of radiation as Chernobyl.

This is all academic because it is highly unlikely that fuel pool will be compromised. It was reinforced after the initial incident and the are plenty of facilities to get cooling to it.

The reports of impending disaster are reporting hazards which have been considered as event which are going to happen. The two are not the same thing.

[Globs]

Talksteer said:

This is all academic because it is highly unlikely that fuel pool will be compromised.

Oh?
I reckon a decent earthquake would have it down in seconds..



....now where are we likely to have one of those?

[Digby]

Any truth to this?

http://theintelhub.com/2012/04/22/fukushima-is-fal...


"Seismicity standards rate the building at a zero, meaning even a small earthquake could send it into a heap of rubble. And sitting at the top of the building, in a pool that is cracked, leaking, and precarious even without an earthquake, are 1565 fuel rods (give or take a few), some of them “fresh fuel” that was ready to go into the reactor on the morning of March 11th when the earthquake and tsunami hit.

If they are MOX fuel, containing 6% plutonium, one fuel rod has the potential to kill 2.89 billion people. If this pool collapses, as Senator Wyden is now saying too, we would face a mass extinction event from the release of radiation in those rods."

[Globs]

Ironically the 'fresh fuel' is the safest bit of the whole bundle - it's the fuel that was most recently taken out that's by far the most dangerous.

IIRC #3 used MOX, and that was blown to pieces, pool and all - some say as a result of a nuclear detonation triggered by a hydrogen explosion. Certainly it was a high impact detonation beyond the normal hydrogen explosion.

But yes - I agree #4 pool is something to be extremely worried about, especially as the people tasked to look after it are barely capable of running a bath, let along a crumbling nuclear facility (that they let melt down) in an earthquake zone.

[AlfaFoxtrot]

Digby said:

Any truth to this?

http://theintelhub.com/2012/04/22/fukushima-is-fal...


"Seismicity standards rate the building at a zero, meaning even a small earthquake could send it into a heap of rubble. And sitting at the top of the building, in a pool that is cracked, leaking, and precarious even without an earthquake, are 1565 fuel rods (give or take a few), some of them “fresh fuel” that was ready to go into the reactor on the morning of March 11th when the earthquake and tsunami hit.

If they are MOX fuel, containing 6% plutonium, one fuel rod has the potential to kill 2.89 billion people. If this pool collapses, as Senator Wyden is now saying too, we would face a mass extinction event from the release of radiation in those rods."

Apart from the obvious sensationalist nature of the article, some references to back up any of the claims would be nice. How is one fuel rod supposed to kill billions of people? Why are these 'dangerous' levels of radiation across the US not being reported on elsewhere? Why is there a Paypal link at the bottom to 'fund a spectrometer?'. The actual report on the radiation levels in kelp that is referred to (http://www.scientificamerican.com/article.cfm?id=radioactive-iodine-from-from-fukushima-found-in-california-kelp) seems to reach a rather different conclusion to the author. I therefore suspect that the seismic report is being similarly misreported by someone who has a clear agenda of their own, which bears little resemblance to facts...

[Welshbeef]

I guess the high casualties come from the proximity to China and an assumed radioactive discharge over vast areas of China.

[hairykrishna]

It's nonsense. Apply some critical thinking - how could 2.89 billion people possibly be exposed to it?

Assuming they've done any kind of calculation at all I presume they've done some maths similar to that found here; http://www.phyast.pitt.edu/~blc/book/chapter13.htm... where they calculate potential cancers per pound of plutonium dust inhaled. They've then multiplied this up by the amount of plut present.

It's analogous to suggesting that, because a cup full of water can drown someone, a swimming pool 'has the potential to kill millions'.

[Welshbeef]

What about making fertile land and sea not viable for food production of grazing for centuries. Could famine be another part of the 2.89 billion