Japan Earthquake: nuclear plants

A few weeks ago we saw estimations of total amount av radioactive materials emitted to the atmosphere made by NSC and I think Tepco. Should these estimations be updated now since we since then now know there has been a meltdown in #1, #2, and #3?

Has anyone made an estimation yet of the total amount of radioactive material emitted directly to the sea?

http://ex-skf.blogspot.com/2011/05/m...ars-up-to.html

Wait... what? Oo

Exactly my thought.... and... "How?"

How is it technically possible to let this happen??

And... "Let's cool it with seawater" (yes, that's sarcasm).

Sarcasm seems uncalled for.
When that decision was made, quite reluctantly and perhaps too late, there was no other way to try to cool the reactors.
We should always remember the site is in the middle of a disaster zone, with 25,000 people dead and many times that number homeless.

None taken I was simply defending my idea that the core shroud could fit through a hole of that size in response to your picture that suggested it was impossible due to physical size constraints. There are good arguments against that being the actual ingress point for the new core shroud, but, "It won't fit," isn't one of them.


My central contention in all this is that the green box/framework/hole thing could have had something to do with the core shroud replacement project, not that that spot was definitively the location of core shroud ingress. I really don't care how they got them in and out of the building. The core shroud replacement job is much more than a routine refueling outage. There must be (literally) tons of extra equipment and tools needed above and beyond what's normally in the reactor building, and maybe whatever was happening on the low roof in the SE corner of the building was in a support role for all that extra stuff.

The explosions in buildings 1 and 3 have been attributed to a buildup of H2 gas that escaped from primary containments. The etiology of the building 4 explosion must have been very different. Did the green box/framework/hole apparition and/or the core shroud replacement work contribute to the explosion of building 4? I think we're no closer to answering that question than we were on 12 March.

The TEPCO operational manual says the reactor's temperature should not be allowed to fall at a rate of 55 C per hour or more, and isolation condenser operations should be adjusted to prevent such an occurrence.

TEPCO said its workers halted the cooling system because it had caused excessive cooling, with the reactor temperature falling more than 100 C in the time the condenser had been operating.

I'm referring (see the link I quoted in my post) to the sodium-cooled fast breeder that apparently swallowed a 3.3 tonne loading machine they now can't retrieve. Just a few months after the first restart in >15 years after the last incident there (15 years that included a technical overhaul). They apparently can't let it run for much more than a year without something terrible happening. It's just radioactive sodium and MOx-fuel.

Do not condemn until you have walked in their shoes.

I see we are back to armchair blaming TEPCO management and engineers. Please move this part of the discussion elsewhere.

Just in case you all forgot:

Results of air sampling from above reactors 1 & 4 is out, not sure I've seen this mentioned here till now?

http://www.tepco.co.jp/en/nu/fukushi...10524_01-e.pdf

Numbers too low to cause much excitement? Not that these reactors were looking like the best candidates for giving off the largest releases, and Im not entirely sure about TEPCOs choice of sampling point above each building either. Whats located in the corner of unit one that they chose?

(photos showing sampling locations here http://www.tepco.co.jp/en/news/110311/index-e.html )

I am reading info stating almost 200 sieverts per hour at reactor 1. Is this believable?

http://webcache.googleusercontent.co.../+%3Ca%20href=

I am reading info stating almost 200 sieverts per hour at reactor 1. Is this believable?

http://webcache.googleusercontent.co.../+%3Ca%20href=

My apologies, I did not see the "instrument failure" next to graph.

some days ago it show 5000Sv in unit 4... tepco data is first and best information source...

Could the explosion in building 3 have been within the reactor core, and blown its lid off so that it is now exposed to the air?