Earthquake/Tsunami Thread - FG Members Check In.

The sensible majority is sensible enough to realize that being sensible means tolerating idiots foaming at the mouth once in a while to remain in a sensible county.
 
Google has launched a Person Finder tool for this disaster (as they did for Haiti and the last tsunami). Here is a link:
http://japan.person-finder.appspot.com/?lang=en

If you are looking for someone or want to check in so you can be found, please make use of this service.
 
Seeing as noone else has posted. Video and images of the explosion at reactor 1 Fukishima
Many are being removed.
http://www.twitvid.com/LICNU
256502872.jpg

256502872.jpg

http://i.imgur.com/syu6K.jpg

Live updates from :
http://www.bbc.co.uk/news/world-middle-east-12307698#video

Video showing the moment of explosion and shockwave.
http://live.reuters.com/Event/Japan_earthquake2
 
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Oh, damn this is bad.

Really getting worried now.
 
This really is starting to get serious....

Hopefully everything stays under control.
 
Well guys, sure, it was an explosion, but it looks like a steam explosion. The damage is not _as_ massive as it seems, the building is basically a frame with some sheet metal on it, and that blew off. Not a complete meltdown yet.......but some radiation seems to have leaked.
 
My .jp acquaintances are translating and posting on one of my other forums - should I take up relay/reporting duties again?
 
D-Fence said:
.......but some radiation seems to have leaked.
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Wasn't that *somewhat* intentional? (can't think of another word right now) There was a report that they had to release a certain quantity of steam to relieve pressure inside one of the reactors, and that some radiation would inevitably escape during that process.
 
vikiradTG2007 said:
Wasn't that *somewhat* intentional? (can't think of another word right now) There was a report that they had to release a certain quantity of steam to relieve pressure inside one of the reactors, and that some radiation would inevitably escape during that process.
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Not on this scale, and it shouldn't have resulted in the building disintegrating.


Edit:
Here's some commentary that pretty much sums it up.
The outer, weather shell of the building is gone. If the containment was of the domed design, it is gone, too. If if is of the mushroom-flattop design, it appears to be Ok, or at least it may be Ok from pictures.

The problem is they cannot produce power for cooling water pumps from generators at plant, or get it in from outside plant.

This can lead to a cascading series of problems where 3 to 5 reactors are lost.
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Fukushima 1 reactor #1 external building concrete cover is gone. #1 is an old 460 MW boiling water reactor (BWR).

The state of the primary containment (see link on BWR) remains unknown.
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The problems seem to be with the older designs at the installation, being a BWR dating back to 1971, and the design is the same for 1, 2, and 3, with Unit 1 having lost the outer shell of the containment building. Apparently units 4 and 5 are of post-Three Mile Island design and have shut down properly
 
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vikiradTG2007 said:
I meant several hours prior to the explosion, I think it was last night (GMT).
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Yes, that was the cesium-137 that was detected - that would have escaped when one of the pressure relief valves popped and bled off some of the steam. Let me go try to find an explanation that someone posted elsewhere last night as to what's supposed to happen. Cesium 137 has a very short biological half-life (70 days) and is pretty easy to treat with a common chemical (Prussian Blue). Cesium 137 poisoning/contamination is actually surprisingly common, relatively speaking.

Do keep in mind that there was already a 10km zone evacuated around the reactor and they maintained containment for a bit more than 24 hours, long enough for people to get out of the immediate danger area.
 
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vikiradTG2007 said:
I meant several hours prior to the explosion, I think it was last night (GMT).
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Yes, that's right.

AFAIK there's no news directly relating the explosion to any leak of contamination.

Spectre said:
Apparently units 4 and 5 are of post-Three Mile Island design and have shut down properly
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I believe they all shut down properly, it's the decay heat they are dealing with.
 
hansvonaxion said:
I believe they all shut down properly, it's the decay heat they are dealing with.
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I've seen mixed reports on that - I'd heard that #1 didn't scram or didn't scram completely (reason: unstated) and that was part of the problem.
 
Spectre said:
Do keep in mind that there was already a 10km zone evacuated around the reactor and they maintained containment for a bit more than 24 hours, long enough for people to get out of the immediate danger area.
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At that time it was a 2 or 3km evacuation and 10km was an advisory to stay indoors. I think it's been changed to 10km evcuation only after the explosion.
 
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hansvonaxion said:
At that time it was a 2km evacuation and 10km was an advisory to stay indoors. I think it's been changed to 10km evcuation only after the explosion.
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Will look for referents for that now, I'd read differently. :dunno:

Here's the piece I mentioned above. Keep in mind this was posted last night, long before this explosion.
I?ve worked in the US nuclear industry for 30+ years and for 18 years I was a licensed senior reactor operator/control room supervisor on a boiling water reactor (BWR) similar to the Fukushima plant. I helped write the emergency procedure guidelines that are used at US BWRs. There is a great deal of information flying around that just does not make sense. There just seems to be no detailed technical information getting out to the public on this. At the risk of over simplifying the system, a BWR is like a giant pot of boiling water. Regular light water, not heavy water, goes through the reactor, is heated by the splitting of uranium atoms, turns to steam and spins a turbine-generator to make electricity. The steam is condensed back to water and pumped back into the reactor to continue the cycle.

There are 3 basic barriers to the release of radiation: the metal clad that encases the uranium fuel, the reactor pressure vessel, and the containment. If 2 of these 3 are compromised, and the third is in jeopardy, US plants will advise shelter or evacuation of nearby residents.

The reactor operates at a normal pressure of about 1000 psig. During an earthquake of this magnitude, the reactor would be expected to automatically shut down (called a reactor scram). Control rods are hydraulically driven into the core in less than 7 seconds. I do not know if this took place but if it did not, we?d probably hear about it because it would be such a big deal. Even with rods inserted, the reactor continues to produce heat equivalent to about 3% of its full power level. This is not the same as taking a pot off the stove and letting it cool. There are still some atoms splitting and fission products decaying that produce heat. This drops off slowly and is why there needs to be layers of redundant cooling with backup power. During such an earthquake, power from outside the plant would not be expected to be available.

The plants have several back up diesel generators (locomotive style engines) that supply power to motor driven cooling systems that will supply high flow of water up to about 300 psig.. There are also steam driven systems to supply cooling water up to 1100 psig. There are also pressure relief systems that active at about 1100 psig. If reactor pressure gets too high, relief valves open and discharge steam to a water filled pool inside the containment.

Here are some information being reported that does not make sense. Reports that the pressure is 1.5 times normal; incorrect. There are at least 10 relief valves and any one can handle the energy after a plant shut down. CNN reports the US military has flown coolant to the site, but the coolant they use is regular water; I can?t imagine why the US would need to fly in coolant.


Right now I?d want to know a few things.


Are all rods fully inserted? What is the water level in the reactor? It?s normally about 12 feet above the top of the fuel. What injection systems are available? What is the reactor pressure? What is the status of containment?


Based on limited information, this is what I think might happen:


Earthquake hits, high vibration on the main turbine automatically trips the turbine by rapidly closing stop valves. Reactor automatically shuts down (scrams) all rods go in. Earthquake disrupts off site power to the plant and back up diesel generators should have started, maybe they did not. Main sources of water to the reactor are not available. If there is no pipe break off of the reactor, the pressure will slowly increase. After about an hour, a relief valve(1 of about 10) will open at about 1100 psig and drop pressure to about 1080. The steam is sent to a pool of water called a suppression pool in the containment that condenses the steam. This valve will cycle open and close every 5-10 minutes. Operators would use a small steam driven turbine (RCIC) to supply water at high pressure to the reactor under these circumstances for several hours. You can sit like this a long time, hot and at 1000 psig it?s no big deal as long as water covers the fuel in the reactor pressure vessel. If that turbine is not available, there is a larger steam driven turbine (HPCI) that supplies more water meant to provide make up if there was a pipe break.

If neither of these systems is available, the relief valve will continue to cycle and reactor water level will slowly drop. At some point before the water level lowers to the point of uncovering the fuel, all the relief valves would be open (ADS) and pressure would be reduced to below 300 psig to allow the low pressure but high flow systems (CS & LPCI) to restore water level and cooling. These pumps however, need electricity, like from the diesel generators, to run. If things get this far but there is no injection, in US plants there are things like diesel fire pumps that can be tied in to provide alternate sources of water. I?m not sure if they are set up to do this in Japan. Without cooling, eventually the fuel temperature will exceed 2200 deg F and the clad will melt. Fission products that are highly radioactive will get dispersed into the reactor vessel. If there is a pipe break or relief valve open, those fission fragments get dispersed through containment.
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Edit: Found this from earlier today: http://english.kyodonews.jp/news/2011/03/76992.html - the 10km evacuation radius had been emplaced earlier in the day, prior to the explosion (the article predates it).
 
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