FACTBOX-Experts on explosion at Japan nuclear plant

[jpak]

http://af.reuters.com/article/energyOilNews/idAFLDE72C06R20110313

March 13 (Reuters) - Japan was fighting to stop fuel rods in two earthquake-damaged reactors at the Fukushima Daiichi plant from overheating after some controlled radiation leaks into the air to relieve pressure.

The government said a building housing one reactor was at risk of exploding after a blast blew the roof off the first the day before at the complex, 240 km (150 miles) north of Tokyo.

The fear is that if the fuel rods do not cool, they could melt the container that houses the core, or even explode, releasing radioactive material into the wind.

Here are comments from experts:

PADDY REGAN, NUCLEAR PHYSICIST, SURREY UNIVERSITY, UK

(Speaking on Sky News)

"If there is a meltdown, which basically would mean the fuel inside the reactor becomes so hot that basically the cladding that holds it in place ... melts, that can release the radioactivity that comes from the fission cells."

<much more>

[kristopher]

1. I just watched PM Kan prepare the Japanese people for something bad

He told the Japanese people in a Sunday afternoon address that Japan was facing the toughest, most difficult crisis in the 65 years since WWII. He asked them for their understanding and warned of coming "planned" power shut downs in Tokyo for an unknown duration.

He then turned the mic over to a Mr. Edano (Chief Cabinet Secretary) who briefed on reactor 3. He stated "About #3 reactor in Fukushima Power Plant. A short while ago they started the sea water injection into the reactor and the level of water has risen. It has risen to a certain level and then it seems that the gauge is showing the level of water is not going up however the supply of water continues. We do not know what to make of this fact. Yesterday ever since the explosion in the #1 reactor the situation like this is continuing, now #3 reactor vault might be showing some failure. And the failure in the vault has to be solved and the air pressure inside has to be lowered (said forcefully). And currently the radiation monitor hasn't shown any change. That is the situation in reactor #3."

Asked for details he added that "it is possible there is a malfunction of the valve to remove the air, we are trying resolve this issue right now". Don't let this phrasing fool you, it is a statement that there is a problem with the relief valve and they can't vent the pressure.

They seem frightened and emotional.

To appreciate this it might help to know that when someone is ill and dying there they are not informed of their disease nor prognosis. Instead they are told by family and doctor that they are suffering some temporary malady that will pass soon enough with the proper care.

Some things can't be hidden however and the sick person understands from the circumstances and people's behavior that there is a real problem. They rarely pursue their suspicions, instead they trust the judgment of the significant others in their life to ensure there well being to the extent possible.

Watching this I was left with the feeling that was the type of message that had been conveyed. I think they are in a race between the pressure limits of containment and how fast they can cool the core. IMO It is a race they do not think they can win.

[madokie]

2. So many times on this board have I been told I was a fool for opposing nuclear power

So many times I've been spot on
Same goes for you Kris, Jpak and others here, we were shouted down by a few loud mouths with so little knowledge, irregardless of their education level.

Sad day for the world

[LiberalEsto]

3. Amen

But I suspect some of these are paid shills

[Kolesar]

5. The designers f-ed up this design more than I expected

I had more faith in them. My opposition to nuclear power is rooted in the corruption and malfeasance that I have seen at every phase of the nuclear industry: uranium mining, lying to NRC inspectors*, irresponsible dumping at Piketon & Hanford, and greedy contractors at Rocky Flats.

*Kolesar plays the Davis-Besse card!

[FBaggins]

7. Don't know how many times...

... But you can add one to it if you replace "fool" with "wrong"

[madokie]

9. I wasn't wrong then and I'm not wrong now

Now pay the fuck attention, will you?

[FBaggins]

11. Of course you were.

Just as you can't seem to keep a civil tongue in your head. :)

[madokie]

13. and you can't seem to pay attention to the subject at hand

The king of, hey look over there.
I've been reading you for a while now so I know of what I just said.

[FBaggins]

14. I have no problem paying attention to the subject at hand.

It's just that the story at hand does not equal "proof that we never should have gone down the road of nuclear power and we should back off from it now". It's not even close.

The king of, hey look over there.

You mean like... "10,000 people are already dead... but HEY, look over there... we could end with hundreds sick and maybe even a few dying! THAT's the important story!"

[madokie]

15. Can I ask a question of you

what kind of work do you do?
No reason other than to try to get a feel for where you're coming from.
Construction work and creator of inanimate objects here.
And to create something useful takes a lot of study and hard work so I'm comfortable with both

[FBaggins]

17. Sure. You can always ask.

I'm currently a senior designer/developer (systems and curriculum) in the T&D field.

But I majored in Physics (among other things - I'll be a student until I die) and spent a little time with a reactor or two under water. I've had an interest in the subject for most of my adult life. My construction experience is limited to mid-level DIY projects (finished basement, attic, home repairs, that sort of thing).

I've got to ask... What does "creator of inanimate objects" mean?

[Kolesar]

21. Proves we never should have gone down the road of nuclear power and we should back off from it now

Nice use of clauses. Could not have said it better myself
:applause:

[FBaggins]

22. Lol...

...except that I offered it as something that was NOT true.

But thanks for appreciating a turn of phrase. :)

[Kolesar]

23. Whoooosh

right over your head

[Kolesar]

4. Presumably, sea water is their best tactic to stop the neutrons in the reaction

1. to stop neutrons in the reaction
2. to cool the reactor core

If it is a partial meltdown, that would mean that they cannot push the carbon control rods back into the reactor. I don't know if they can stop this reactor.

[jpak]

8. According the the Nature.com blog - they could not fill F No. 1 for the same reason

There is a structural failure in both...

[FBaggins]

12. Yeah... but where?

Sounds like it's a leak in the pool part way up the wall?

Does raise a potential design issue related to building these things above ground rather than set down into it.

[jpak]

16. Either the quake, or the tsunami or the hydrogen explosion opened something up

I suspect it's too hot to make a thorough inspection.

[FBaggins]

18. Presumably so. Have you read anything about tsunami impact?

There's obviously a common design issue with all of these reactors (and no... it's not "they're nuclear reactors dummy! Duh!") :)

The facility is not just close to the epicenter of the earthquake, but it's right along the coast (though not directly exposed). I've only seen one report that mentioned a tsunami impact, and that one phase of pumping had to stop when another tsunami alert went out. Is it possible that there was flooding in all of the auxiliary diesel generator rooms?

I'm pretty sure that each unit had it's own generators, so I'm looking for a common factor that would account for essentially all of them failing. Maybe flooding... maybe they don't have their own fuel tanks and some form of distribution piping was compromised... I don't know.

And as before... they just won't take my calls over there. :)

[Wilms]

19. The reports I've read, for what it's worth, claim the tsunami took out the back-up gen.

Good point you make. Was it the fuel rather then the gens?

I'm shocked that these gens might not have been elevated to avoid tsunami flooding.

[FBaggins]

20. I agree. I'm not sure how you can design for earthquakes...

...yet not for things that often come with earthquakes where you happen to be building the plant?

[Strelnikov_]

6. If one of the crippled reactors does suffer a catastrophic 'event', they lose 4.5 GW

Probably why they are warning of blackouts.

Yet, I was told on the DU just yesterday that putting six reactors right next to each other is a good thing.

[FBaggins]

10. They've already lost those GWs.

The reactors have obviously been "off" for some time now.

Indeed, they've lost some of that production permanently (at least one and probably two of the reactors), and the rest will be out for months even in a best-case scenario.

Even the three that were shut down for maintenance at the time of the earthquake can't be safely used until a great deal of inspection and possibly repair is completed... and I'm sure that any resources that would otherwise go to that effort will be busy for months studying what happened in the other units (which of course can't start until it stops "happening").

On the flip side, power demands are (sadly) probably lots lower right now too.