...Nuclear MELTDOWN in Japan, is US Threatened???


Look at this explosion at 47 seconds into the video. A violent hydrogen explosion, demolishing such a heavily reinforced containment building, must have been the result of a badly overheated reactor.
Japan claims the reactor is intact. But that large of an explosion could have caused all kinds of damage and leaks that have yet to be found, or admitted by the Japanese govt.
Japan Nuclear Reactor EXPLOSION Fukushima Meltdown
http://www.youtube.com/watch?v=LvC4WQrQwTs

Japan Nuclear Fallout Map? (gulp)
http://img847.imageshack.us/img847/438/fallout.jpg
Fukushima overhead view
http://everist.org/pics/misc/fukushima_worse.png
Japan is reporting the prevailing winds are out to sea. They've already evacuated 300,000 from the area. And Fukushima #1 is one of the largest 25 reactors in the world. And was built ...way back..in 1970. The first reactor built by it's builder.
s
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I can't help feeling that given that Japan is frequently the subject of tsunamis (even if not usually this bad), and that there is a clear link between tsunamis and earthquakes, the nuclear plant backup generators should have been in a place that is hardened so as to resist a tsunami.
Sylvia.
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plants werent built to survive much more than a 7.1 since larger earthquakes are very rare, and the plants would cost ar more.
news now reports 2 reactors exploded and 6 are in trouble.
if the core melts down completely does anyone really know what will happen?
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I think there are no more problems. In Chernobyl, the core is operational when it explodes. In Japan, the control rods were lowered that controls and stopped the nuclear reactions, so it's not getting hot anymore and I think what they are doing are simply lowering the temperature that occured before it shuts off. So there may not be in danger anymore.. unless the control rods fail to lower down? The control rods absorb neutrons from the uranium.
During a real meltdown, the nuclear reaction continues and the uranium becomes molten and bore thru the 6 inches of stainless steel and if it bore thru the cement floor, it can get underneath the facility and when it reacts with water, it can contaminate the surrounding, even if it didn't get out of the cement floor, if it explodes inside the air contamination can also get out.
But the problem in japan seems to be minor now because the nuclear reactions are no longer occuring and it is only the prior temperature of the reactor that is being lowered, right?
Btw... how many miles in outer space before leaking nuclear fuels are no longer in danger of reaching the earth?
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Apparently the core containers are damaged. This is why they admitted partial meltdown. I don't think the control rods are functioning properly.
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I don't think the core containers are damaged. Where did you hear it? Also the control rods are functionining property. This seem to be what this nuclear expert Fred Mccall is convincing us. That there is nothing to be concerned about. The Japanese are just lowering the temperature which existed prior to the Earthquake. It is no longer producing new heat because the neclear reactions are already off when the control rods are lowered. You were just speculating the control rod didn't function property. We assume they are. If not, then it's going to be a problem because the nuclear reactions can generate new heat... but this is unlikely. Control rods are lowered by simple actuator machine which seldom fail especially in mil spec configuration used in nuclear power plants.
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On this type of reactor, even if the control rods were fully inserted, the core has to be cooled for several days or it'll still melt down. And this very old type of reactor melts down is minutes once the core is exposed.
So IF they're keeping the core cooled by sea-water, which is not part of any recognized failure scenario, all that water would be quickly leaking back out and it would be heavily contaminated. Probably being flushed out to sea.
I think at this point they're trying to keep the core from melting through the steel vessel, if that happened then massive amounts of radiation would be carried away by the winds. Right now it's all going into the sea water I think.
On CNN they're reporting a US helicopter flew through the smoke line and17 crew members were contaminated with radiation.

That's a faulty assumption with these very old reactors, it may be true for most reactors, but these need to be cooled after the rods are fully inserted for an extended period of time.

Most nuclear plants have their control rods held in place above the core by electro-magnets. So if the power fails the rods must fall completely into the core. But not this reactor, they are hydraulically raised from below.
I think the reason these reactors failed, when so many others in the region didn't, is because of their age (1967) and very simple and....cheap design. Right now I bet they're furiously trying to cool those reactors before the wind changes to the south.
Right now any radiation is going out to sea in the water and wind. But in a day or two, the winds could shift south and the radiation could contaminate the ...entire nation.
Quite a drama going on right now over there I bet.
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Cite that this is somehow different from other reactors?

You don't seem to understand. No water comes out except as steam. What they're doing is called 'pump and dump' and while it's not something you want to be in the position of having to do, it's certainly a 'recognized failure scenario'.

Well, no, you DON'T think. That's part of the problem.

Again you trot your ignorance out for all to see. Please provide a cite that shows that this is any different from any other nuclear reactor.

I think you're an ignorant fool. I'd bet what I think is right and what you think is, well, foolish.
--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
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On Mon, 14 Mar 2011 21:09:30 -0700, Fred J. McCall

Everything that comes in contact with the core is contamninated. Ocean water will spreaad the radioactivity all over the world. If the BP oil mess didn't stop people from eating sea food, they better stop now.
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