Japan Earthquake

Japan Earthquake | Page 1359

The first big (7-fold) jump in drywell rads is shown as 0800 on 22 May, after a night of (maybe) mysterious flashes and very heavy steaming generally www.tepco.co.jp I don't know what the Japanes figures at the bottom of the columns say, 'we don't believe this!' probably.
by hudebnik 5/24/2011 12:13:26 PM

@hudebnik - Oh, they're DEFINITELY mysterious, my friend.
by Rob in SF 5/24/2011 12:15:55 PM

Google tells me it means 'instrument failure', in which case why are the insts providing continuous and varying records? First rule of disasters - if you don't like what the instruments are telling you, don't believe them!
by hudebnik 5/24/2011 12:18:39 PM

@hudebnik - Let's revisit that chart in the hopes that someone can explain it...
images.scribblelive.com
by Rob in SF 5/24/2011 12:19:12 PM

@hudebnik - It was a software glitch, someone accidentally removed the ÷5 filter they had working on that sensor. It's back now.
by Rob in SF 5/24/2011 12:22:42 PM

A bit of radiation background info www.benlovejoy.com
by hudebnik 5/24/2011 12:29:49 PM

"Now let's look at Chernobyl ...
Radiation levels in the control room immediately after the explosion reached around 300 Sv/hr - providing a lethal dose in 1-2 minutes.
Almost 22 years later, levels inside the reactor hall today are approximately 34 Sv/hr - a lethal dose in 10-20 minutes. Not really somewhere you'd want to include in the itinary.
"
by hudebnik 5/24/2011 12:31:01 PM

@hudebnik Yeah, heavy. Reminds me of this Chernobyl video.
by Rob in SF 5/24/2011 12:34:00 PM

@hudebnik So a 400 svh drywell could be a real reading. Not an error.
by lillymunster 5/24/2011 12:36:04 PM

@lillymunster Seems like that would be easy to have in the D/W after a meltdown with an RPV breach. Nay? 300 Sv in the control room!
by Rob in SF 5/24/2011 12:38:07 PM

So if that 400 svh reading in #3's drywell is an accurate reading that makes the theory of corium residing there more likely. IIRC there was a high supression chamber reading recently? Maybe corium dropping bits into the standing water below making tons of steam.
by lillymunster 5/24/2011 12:40:16 PM

@lillymunster Seems quite probable to me. And all just venting away with the containment cap blown off.
by Rob in SF 5/24/2011 12:43:33 PM

"Corium (and also highly irradiated uranium fuel) has an interesting property: spontaneous dust generation, or spontaneous self-sputtering of the surface. The alpha decay of isotopes inside the glassy structure causes Coulomb explosions, degrading the material and releasing submicron particles from its surface.[42] However the level of radioactivity is such that during one hundred years the self irradiation of the lava (2 × 1016 α decays per gram and 2 to 5 × 105 Gy of β or γ) will fall short of the level of self irradiation which is required to greatly change the properties of glass (1018 α decays per gram and 108 to 109 Gy of β or γ). Also the rate of dissolution of the lava in water is very low (10−7 g·cm−2 day−1) suggesting that the lava is unlikely to dissolve in water." en.wikipedia.org(nuclear_reactor)
by Edano 5/24/2011 12:43:39 PM

does anyone know how to read this expression? 3.98E-01SVH
by lillymunster 5/24/2011 12:44:04 PM

Hmm. Now I wonder what was the source for the high reading. I remember it being debated in recent days as a bad gauge.
by lillymunster 5/24/2011 12:48:04 PM

We're up to 48 poll respondents. Seems we're skewing a bit differently than Rasmussen's peeps.
by Rob in SF 5/24/2011 12:48:36 PM

#2 suppression chamber is around 4.5 - 5.0E+01 = 50Sv/hr?
by hudebnik 5/24/2011 12:50:31 PM

@lillymunster - You removed your Wanted Badge of Courage?
by Rob in SF 5/24/2011 12:50:37 PM

So 200Sv/hr in the #1 drywell after a complete meltdown is not so unlikely?
by hudebnik 5/24/2011 12:55:29 PM

@Rob in SF I had to log in as a mod, liveupdate was crashing in my normal login.
by lillymunster 5/24/2011 12:56:10 PM

@Edano - "Decimal notation is the writing of numbers in a base-10 numeral system." en.wikipedia.org
by Rob in SF 5/24/2011 12:56:16 PM

Nancy -- high readings are #1 DW CAMS. I saw on Sunday it was way up there.
by Markfm 5/24/2011 12:57:13 PM

Gosh the stuff you learn here, it's like doing an online degree.
by hudebnik 5/24/2011 12:57:23 PM

@Edano It was a lame joke, I've seen math written in non-base-10 notation and it's very confusing...
by Rob in SF 5/24/2011 12:57:57 PM

@Rob in SF : base-2 (dual) or base-16 (hex) is for computers.
by Edano 5/24/2011 12:59:30 PM

@hudebnik hence why I am just sitting back watching now! lol
by Angie 5/24/2011 1:00:38 PM

21 May 6:00 36 Sv/hr. 22 May 12:00 196 Sv/hr. 23 May 6:00 33 Sv/hr. Something really spiked it on Sunday, else it has issues.
by Markfm 5/24/2011 1:00:59 PM

@Edano There you go. I dealt with Base-2 in my punch-card/punch-tape days... I have enough trouble with Base-10.
by Rob in SF 5/24/2011 1:02:11 PM

@Edano Base-12 is I think what confused the daylights out of me.
by Rob in SF 5/24/2011 1:02:57 PM

@markfm - Saturday night/Sunday morning was when we had the strange flash phenomena and a LOT of steam. Any connection do you think?
by hudebnik 5/24/2011 1:03:26 PM