Japan Earthquake

Japan Earthquake | Page 1148

I had commented last week about how the "sensitive" report, where people were thinking something big and bad was going to happen, was likely related to not messing up the air purification on #1 and not leaking water being transferred -- looks like TEPCO still cannot pump water cleanly.
by Markfm 5/13/2011 3:55:09 PM

TEPCO to review No. 1 reactor plan www3.nhk.or.jp "On Friday, workers brought in equipment for connecting a circulating cooling system to the reactor, in line with a plan TEPCO decided last month.

Under the plan, the utility was to fill the No. 1 reactor containment vessel with water. A cooling system was to be set up that would circulate this water through a heat exchanger.

But this system will only work if the water in the containment vessel is at least 5 meters deep."
by Markfm 5/13/2011 3:56:59 PM

In the US, Panel on Nuclear Waste Disposal to Propose Above-Ground Storage www.nytimes.com
by Markfm 5/13/2011 4:04:37 PM

As we have discussed before, water is both a modifier and a facilitator of fission. So if/when they manage to raise the water level inside the RPV, with control rods melted, will fission restart? I hope Tepco is considering all permutations of their plan. But I don't have high confidence they are doing so.
by marie rich 5/13/2011 4:05:32 PM

I'd like to know if the vent valve is 'unstuck' for #1. Hard to believe that they wouldn't lower the pressure in a damaged plant if they could do so easily. So, again, if/when they manage to get water back in, won't there be a danger of flash steam and resultant pressure spike?
by marie rich 5/13/2011 4:09:07 PM

In #1, given the rods being fully exposed, I expect they're fully melted, so perhaps covered by 2 meters of water? (it sounds like the bottom of rods is at about +4m from bottom of vessel, and the actual water level is at about 1 m below nominal bottom of rods) It sounds like there really should be a "glob" on the bottom, I don't know how much water there really is between chunks of radioactive material, or if it really is more like a sheet or mushroom, with water then lying above and around it.
by Markfm 5/13/2011 4:09:55 PM

No idea if either the pressure or temp sensors are OK -- it would be nice to think that "only" the water level sensors are off. #1 temps are overall reported fairly low, sounds like around 90C at the bottom of the vessel (the part with water covering it), while 114C at the feedwater point (presumably high up in the RPV).
by Markfm 5/13/2011 4:12:05 PM

@Markfm The surface of corium, iirc, is like pitted lava, with bubbles rising to the surface. Those bubbles can "stir up" the imperfect blend of corium. Btw, this is a very pertinent article about the effects of fallout on Fukushima environment;it's good. web.mit.edu
by marie rich 5/13/2011 4:13:46 PM

From the paper posted below: In facing such important and far-reaching decisions about trade-offs, it is important to keep in
mind the nature of our radiation risk estimates, their primary purpose, and how they were
developed. Radiation risk estimates were not generated to address the hazards of living in a
contaminated environment. They have been generated in order to establish radiation protection
guidelines for the workplace1. These situations are so different, and have such drastically
different requirements for citizens, they require equally different approaches to addressing the
radiation hazard.
by marie rich 5/13/2011 4:15:59 PM

Here's the latest NIRS fact sheet -good for a quick summary www.nirs.org
by UKVal 5/13/2011 4:16:33 PM

I added it over on the wiki Links page. No idea if anyone else ever looks at it, but I use it as a scratchpad for things that people have found.
by Markfm 5/13/2011 4:17:00 PM

@Markfm I look, but I don't always get it!
by marie rich 5/13/2011 4:17:39 PM

It's a hodge-podge, needs sorting. I believe Rob, though maybe it was Nancy, did a nice cleanup on it about two weeks ago.
by Markfm 5/13/2011 4:18:46 PM

That's why I can find things like reactor pool sizes -- I know I had posted the link over there.
by Markfm 5/13/2011 4:19:17 PM

@Markfm You have an excellent memory, as does Nancy.
by marie rich 5/13/2011 4:20:11 PM

concrete melts at ~1100 °C de.wikipedia.org(Reaktortechnik)
by Edano 5/13/2011 4:22:35 PM

Concerning #1 and venting, I have to believe they simply cannot. On the bright side, as I said before it is self-correcting -- 1 clearly has major leaks, so excess pressure will blow out the leak points. The down side, of course, is that if the existing holes/cracks aren't big enough, they will get bigger.
by Markfm 5/13/2011 4:27:28 PM

insp.pnnl.gov
insp.pnnl.gov
chernobyl corium
by Edano via Insp.pnnl.gov 5/13/2011 4:30:05 PM

insp.pnnl.gov
insp.pnnl.gov
chernobyl corium
by Edano via Insp.pnnl.gov 5/13/2011 4:30:05 PM

en.wikipedia.org
by Edano 5/13/2011 4:33:33 PM

Correction on plant parameter changes. Looking at google translate of the last NISA report, they added a second water source, +3 curbic meters/hr on top of the already running injection, so they're now injecting 12 cubic meters/hr total at #3.
by Markfm 5/13/2011 4:33:56 PM

by Edano via Upload.wikimedia.org 5/13/2011 4:36:00 PM

The architect of #2 unit at Hamaoka has spoken about how unsafe a construction it was due to the rock it was built on which is as strong as fukushima's i.e fukushima is built on *(&^ "
translate.googleusercontent.com
by elainekirk 5/13/2011 4:50:58 PM

p.twipple.jp
bizarre leaf trees in the garden at home in northwestern Chiba Prefecture. Is this sick? Or ...
translate.googleusercontent.com
by elainekirk via P.twipple.jp 5/13/2011 4:55:12 PM

@Edano TY-- Info at my fingertips! And I had heard the phrase 'heat knife' but hadn't looked it up yet.
You are very well dressed today Marie :)
by marie rich edited by elainekirk 5/13/2011 4:55:45 PM

lh5.googleusercontent.com
translate.googleusercontent.com
Maebashi-sludge ash cesium from Becquerel 10,000,004 - City Survey
Newsletter May 13 (Friday) at 50 minutes 19 delivery
Maebashi, 13 th, the city's sewage treatment plant, "Water Purification Center, Maebashi," from the bottom ash were collected at 09, announced that radioactive cesium was detected 10,000,004 Becquerel per kilogram. According to the city sewerage department, "but the ash was transported to the outside of the facility after the earthquake, which aim to prevent scattering," trying to.

by elainekirk via Lh5.googleusercontent 5/13/2011 5:05:18 PM

CTBTO cesium-137 air concentrations. www.bfs.de
by Bobby1 via Bfs.de 5/13/2011 5:07:37 PM

400 fuel assemblies in #1 , ~size: 0.09 x 0.09 x 4 (m)
400 x 4 x 0.09 x 0.09 = 13 m³ corium
reactor vessel diameter = 5 m
13 m³ / (pi x 2.5²) = 66 cm corium height in rpv at 100% damage + control rods
is this correct ?
by Edano 5/13/2011 5:10:36 PM

The cesium graph shows that cesium levels have increased in Sweden and Germany, above the levels in Virginia and Sacramento, CA.
by Bobby1 5/13/2011 5:20:07 PM

@elainekirk TYVM. I just got a new outfit. Do you like this one, or should I stay with basic black?
ooo stay in that one it is very flattering
by marie rich edited by elainekirk 5/13/2011 5:20:34 PM

@Edano: Do you know the total volume of the reactor vessel?
by DonnerT 5/13/2011 5:21:00 PM

@DonnerT : have to look it up
by Edano 5/13/2011 5:22:14 PM

@Edano: And the volume of corium if everything that was inside melted into a puddle at the bottom?
by DonnerT 5/13/2011 5:24:16 PM

@DonnerT : 13 m³
by Edano 5/13/2011 5:24:43 PM

Were we able to figure out if we really saw something major happen the other morning on #3, after that quake, or was it just a mirage ??? Noticed the water level is really down in 3 from the NISA report.
by wtm 5/13/2011 5:25:28 PM

@DonnerT : "360-cubic-meter capacity of the pressure vessel"
by Edano 5/13/2011 5:25:37 PM

i calculated 13 cubic meters corium, can be more because the control rods and other materials (brackets, retainers) must be added.
by Edano 5/13/2011 5:28:47 PM

@wtm Well, the smokeshow was a "reflection" so the steamshow was probably "swamp gas". As distinct from radioactive fog, which immediately followed. Next is will-o-the-wisps?
by radioguy 5/13/2011 5:29:40 PM

@Edano: So for round numbers sake say 20 cubic meters of corium and 340 cubic meters of space?
by DonnerT 5/13/2011 5:32:10 PM

@DonnerT : i don't know if the steam dryer and separator would melt, too. i guess yes, at 2800°. they are quite big. but no exact idea.
by Edano 5/13/2011 5:32:57 PM

@DonnerT @Edano Which begs the question, how will Tepco know how much water is needed 'just to cover the corium'?
by marie rich 5/13/2011 5:33:10 PM

It may be a nice even puddle, or a small slag heap
by marie rich 5/13/2011 5:33:37 PM

@Radioguy, well it was sure impressive !!! Actually did look like something major happened. The cam shook, went out a few seconds (during the quake), and then #3 went nuts, before the steam was coming out of the top of it, after heavy smoke was coming out of the lower side of it, almost down at the ground level. It did look like it had blown up or something? Not a word from TEPCO ?
by wtm 5/13/2011 5:34:27 PM