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Another Japan News Thread | 310 comments (310 topical, editorial, 0 hidden)
I meant (none / 0)
The Oil Drum | Fukushima Dai-ichi status and potential outcomes

I have been watching the NHK feed and grimly laughing at the helicopter operation. Here is some info:

Capacity of spent fuel pools: 1200-1500 tons water 15 meters deep
Needed to cover rods: 15 meters, 400-500 tons water

For reactor 3, they think there might be enough water that they only need < 100 tons, perhaps less

One helicopter can drop 7.5 tons/load. BUt it can't hover, due to the radiation level. If I heard right, those on board are limited to 100 mSieverts/hour (check the time units). They had measured 250/hr at 30 meters and 87/hr at 90 meters. They dumped from 90 meters. See image. Looks more like crop dusting. There was one drop which looked a little better, but at the speed they are going, hitting the building with much is not likely.

By email from Joules Burn to Euan Means.

by afew (afew(a in a circle)eurotrib_dot_com) on Thu Mar 17th, 2011 at 12:24:38 PM EST
[ Parent ]
Re: I meant (none / 0)
afew:
Needed to cover rods: 15 meters, 400-500 tons water
I thought that was 15 feet, not metres. Anyway, I estimated 650 tonnes of water upthread, but with the expected evaporation you'd probably need more water than for a cold pool.

So, in what may be my last act of "advising", I'll advise you to cut the jargon. -- My old PhD advisor, to me, 26/2/11
by Carrie (migeru at eurotrib dot com) on Thu Mar 17th, 2011 at 12:28:46 PM EST
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Re: I meant (none / 0)
Yeah, units are the bugbear. But I found the observation of the likelihood of putting very much water in from a moving helicopter at 90 metres up sounded accurate (though may be just truthy).

Fighting forest fires with planes and choppers is not an exact science, at the best of times. But at least they can get in lower than 90m.

by afew (afew(a in a circle)eurotrib_dot_com) on Thu Mar 17th, 2011 at 12:40:32 PM EST
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Re: I meant (none / 0)
I think the more important observation is that even with a perfect hit you'd be adding 7.5 tonnes of water which would raise the water level by only 15 cm when the fuel assemblies are over 4m tall.

So dropping water from helicopters is just useless.

So, in what may be my last act of "advising", I'll advise you to cut the jargon. -- My old PhD advisor, to me, 26/2/11

by Carrie (migeru at eurotrib dot com) on Thu Mar 17th, 2011 at 12:49:25 PM EST
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Re: I meant (none / 0)
I'd written it off as theatre.

I'm not sure for whose benefit.

And don't they have fireboats?

The range and flow of a fireboat must be an order of magnitude or two higher than a truck, surely?

by ThatBritGuy (thatbritguy (at) googlemail.com) on Thu Mar 17th, 2011 at 12:54:25 PM EST
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Re: I meant (none / 0)
That's a damn reckless form of Kabuki.

So, in what may be my last act of "advising", I'll advise you to cut the jargon. -- My old PhD advisor, to me, 26/2/11
by Carrie (migeru at eurotrib dot com) on Thu Mar 17th, 2011 at 12:55:25 PM EST
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Re: I meant (none / 1)
Politicians and Corporate Management seem to have convinced themselves pretending to do something about a situation is the same as doing something.

She believed in nothing; only her skepticism kept her from being an atheist. -- Jean-Paul Sartre
by ATinNM on Thu Mar 17th, 2011 at 01:38:16 PM EST
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Fireboats (none / 0)
Of course they do

(h/t DoDo)

So, in what may be my last act of "advising", I'll advise you to cut the jargon. -- My old PhD advisor, to me, 26/2/11

by Carrie (migeru at eurotrib dot com) on Thu Mar 17th, 2011 at 12:57:22 PM EST
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Re: Fireboats (none / 1)
Addledum: I found the location of the above photo. I estimate the length of the longest water spray at about 130-140 m.

*Lunatic*, n.
One whose delusions are out of fashion.
by DoDo on Sat Mar 19th, 2011 at 03:37:52 AM EST
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Re: I meant (none / 0)
This may not be obvious from tele photos, but if you check on Google maps, any point a ship can stop at is at least 200 m away even from the center of No. 4 (to the south where the cooling water exits), and the more suitable location is 350-400 m away (east of the reservoir).

*Lunatic*, n.
One whose delusions are out of fashion.
by DoDo on Thu Mar 17th, 2011 at 01:28:38 PM EST
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Re: I meant (none / 0)
And 250 m even if you get a ship on the reservoir.

*Lunatic*, n.
One whose delusions are out of fashion.
by DoDo on Thu Mar 17th, 2011 at 01:33:21 PM EST
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Re: I meant (none / 0)
and it might be that theres no access to number 4 from the seaward side. That looks to be where the walls are still standing.

Any idiot can face a crisis - it's day to day living that wears you out.
by ceebs (ceebs (at) eurotrib (dot) com) on Thu Mar 17th, 2011 at 01:41:50 PM EST
[ Parent ]
Current Google Earth view: (none / 1)

I numbered the reactors.

No way firefighting ships can get near enough.

by afew (afew(a in a circle)eurotrib_dot_com) on Thu Mar 17th, 2011 at 01:36:52 PM EST
[ Parent ]
Re: Current Google Earth view: (none / 1)
You can't provide some protection from storm surges and tsunamis and remain accessible to waterships.

So, in what may be my last act of "advising", I'll advise you to cut the jargon. -- My old PhD advisor, to me, 26/2/11
by Carrie (migeru at eurotrib dot com) on Thu Mar 17th, 2011 at 01:38:58 PM EST
[ Parent ]
Re: Current Google Earth view: (none / 1)
Assuming the breakwater is a temporary obstacle that could be removed, and there's no spent fuel in that pool - if that even makes a difference at this point - I make that a distance of around 200m. Which doesn't sound totally impractical.

There's also the advantage of at least some cover from the turbine buildings.

by ThatBritGuy (thatbritguy (at) googlemail.com) on Thu Mar 17th, 2011 at 01:48:21 PM EST
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Re: Current Google Earth view: (none / 1)
250 m. Plus you need to calculate with more due to the height. I looked around and found no fireboat range above 400 feet.

*Lunatic*, n.
One whose delusions are out of fashion.
by DoDo on Thu Mar 17th, 2011 at 02:11:19 PM EST
[ Parent ]

Another Japan News Thread | 310 comments (310 topical, 0 editorial, 0 hidden)
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