Posted on 03/14/2011 12:54:09 AM PDT by SteveH
At the 40-year-old Fukushima Daiichi unit 1, where an explosion Saturday destroyed a building housing the reactor, the spent fuel pool, in accordance with General Electrics design, is placed above the reactor. Tokyo Electric said it was trying to figure out how to maintain water levels in the pools, indicating that the normal safety systems there had failed, too. Failure to keep adequate water levels in a pool would lead to a catastrophic fire, said nuclear experts, some of whom think that unit 1s pool may now be outside.
Victor Gilinsky, a former commissioner at the Nuclear Regulatory Commission, said that to produce hydrogen, temperatures in the reactor core had to be well over 2,000 degrees and as high as 4,000 degrees Fahrenheit. He said a substantial amount of fuel had to be exposed at least at some point.
Thats the significance of the hydrogen it means there was serious fuel damage and probably melting, said Gilinsky, who was at the NRC when Pennsylvanias Three Mile Island reactor had a partial meltdown in 1979. How much? We wont know for a long time. At TMI we didnt know for five years, until the vessels were opened. It was a shock.
(Excerpt) Read more at washingtonpost.com ...
Thanks for the advice. Now my advice, either don’t critique what people post on threads that point to garbage like in post 41, or provide some useful counterarguments. Otherwise this thread is just a bunch of useless fearmongering and I will point that out every time I links like in #41.
The pulse needs to be extremely powerful to even think of frying an off-line diesel generator. Even then, a generator can be quickly repaired.
Most of our testing so far to produce the best EMP is megaton-level nukes in space. Such a thing could take out most (not all) modern active, unshielded, non-hardened electronics in the US. For non-nuclear pulses, you’d have to get right up close to the power plant with a father big bomb because such pulses degrade rather quickly under the inverse-square law.
I saw on another thread that Unit 1 was slated for shutdown (permanent) at the end of this month. From that, one could surmize based on typical refueling cycles, that their last refueling was anywhere between 1 and 2 years ago -- i.e., whatever number of assemblies they offloaded at the last refueling have been cooling for at least one year.
The point is not whether there is no electricity for this cause or another. The point is the fuel rods getting too hot can cause them to melt down and burn, which from what I have read since I got up (not long ago), seems to be happening.
Just because the author doesn’t know a lot about EMP doesn’t mean he doesn’t know about nuclear reactors.
It amazes me how so many here don’t want to admit that anything could go wrong.
And if you think Rawles’ blog is useless then I’m sorry for you.
If you read the whole article the point is that without external electricity the spent fuel rods get hot, whether the lack of electricity is due from one cause or another.
At Fukushima there is no electricity due to earthquake and tsunami damage, but the point is the spent fuel rods not being covered with water plus no electric for water circulation and heat exchange.
And very possibly damage to the holding pool, and pumps.
Surmise == assumption. Yes, I agree that’s reasonable, usually. This is not usual. We avoid assumptions like the plague in such situations.
Afaik, We don’t know how much used fuel was sitting in that upper pit, nor how “hot” it was.
Also: I am very happy to hear that a US helicopter flew into the plume and collected samples. If they know what they are doing they should be able to figure out how roughly how many fuel rods are damaged and definitely if the source of fission by-products is from the reactor or fuel pits.
With respect, if all reactors are designed to contain a meltdown, why did Chernobyl not contain its meltdown? I would say even melting through the bottom of the reactor into the ground has not contained the meltdown, it burned through everything into the ground. It didn’t stop it from burning itself deep into the ground.
Or are you just saying I am being too loose with English and need to be more accurate that the actual fuel that would melt, would actually go down through the bottom of the container into the ground, but the radiation (radioative particles) released if the pressure vessel explodes or cracks will be the actual thing released into the air? Yes we know the fuel does not actually go up, but down, it would be the radiation and radioactive particles that would be released.
But to say that because something is designed to do something, therefore it will always function as designed, is to ignore what happens to things in the real world under the severest conditions. Airplanes are designed not to fall out of the sky, yet we have airplane crashes. We design buildings not to fall and break apart, but yet even the best designed buldings fall down under catastrophic conditions.
If you read my posts across FR on this I am not trying to provoke fear or irrational speculation. If anything I am qualifying my comments heavily with “ifs” and “may” and the like.
You asked a question, I simply attempted to provide you with a reasonable assumption. In the end, it is not important that 'we' know. You can be sure the engineers over there working on getting this under control do know.
You didn’t know, you guessed. Sorry, I’m not letting you off the hook for such a guess without more warnings that you really don’t know posted with it.
And my point that an EMP is not a likely cause short of all-out nuclear war, and in that case a plant losing its cooling is the least of our worries. Nukes that terrorists might use near ground level won't have a very big EMP range due to environmental reasons. There's more danger from the simple physical damage of the explosion, and likely killing all the engineers in the plant.
Quit being so pissy. You asked when they refueled last, and I took a guess based on the factoid of the unit 1 being scheduled for shutdown at the end of this month. It was clearly stated as a quess.
If you don't like my answers, then just skip the hell past them.
No, you're missing it here. Without water which he is assuming requires electrically operated pumps to move.
Of course, there are usually multiple sources of water than can be called upon to re-fill the spent fuel pool before the water all boils off. But virtually all of these systems are dependent upon working, electrically operated pumps to move this water. If control systems have failed due to the EMP and there is no power to operate the pumps (either to add additional water or to pump water through the heat exchangers), then the fuel will ultimately become uncovered.Taking all this as true, if they can get water into the site, his concern is mooted.
From Stricken Japan nuclear plant rocked by 2nd blast:
"Authorities have been pouring sea water into three reactors at the plant after cooling system failures
"
Did you read the article from which I posted the relevant excerpt about spent fuel rods melting and burning if they don’t have water and the heat exchange working due to lack of electricity?
So you think the article by the nuclear enigineer with 30 years in the field I posted is nonsense and just not true. The when he says that the spent fuel rods, if they cannot have influx of water and the heat exchange happening due to lack of electicity, can indeed melt and burn, he’s wrong? Why is this not a danger? Details, not just because you say it isn’t.
Stop being sloppy. I don’t like sloppy answers when I know YOU can do better.
If you have a food pantry, supplies and equipment for emergencies, potassium iodine tablets could well be part of it. But I’d spend the money on a alpha detector and geiger counter first. Priorties. And I don’t think either are needed for the situation in Japan. More for a dirty bomb type of terrorism. Personally I haven’t looked into how to get iodine. I just eat fish regularly.
From Reuters blog:
Masashi Goto, Japanese engineer who helped design the containment vessel for Fukushima reactor, gave press conference with English translation focusing on reactor 3. very informative: www.ustream.tv
comment by Joe at 1:33 PM
If the cooling process stops, the radiation cant be contained anymore. The government is saying reassuring words to say everything is all right. But the public needs to understand that this is beyond what the reactor was designed to withstand. -
Masashi Goto, former Toshiba Nuclear Power Plant Designer who helped design the containment vessel for Fukushima’s reactor core
comment by Mark at 1:32 PM
Plus, if you read the article, the spent fuel doesn’t just need water, it need the water circulating through a heat exchanger.
It’s not a character weakness to look at possible dangers of what’s going on there. Sheesh.
Some of the reactors recently had MOX fuel (mixed oxide, has plutonium in it too) installed or starting up in September. Can’t remember which reactors. One problem is that this kind of fuel melts at a lower temp than regular uranium fuel.
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