Something is odd about this. If the US carrier detected above normal radiation 60-100 miles off shore (depending who you believe distance wise) wouldn't you think the Japanese officials would have reconsidered their decision to only evacuate a 20 km radius??

Japan has finally appealed to the international community for more help in controlling the troublesome reactors.

http://www.businessweek.com...gainst-meltdown.html

[This message has been edited by maryjane (edited 03-14-2011).]

quote Originally posted by Wudman: You have to read beyond any one source and even then, you have to take clues from what they are saying to figure out the real implications.

You are wise my friend. Your words have merit.

Yes the reactors shut down right after the quake.

It takes time for the reactions to subside. During that time the excess heat needs to be dissipated or the core will overheat and the tube that hold the fuel will melt.

I see the problem in expecting the power plants are not going to have issues. Tens of thousands of people died and entire cities have been wiped out. There have been serious fires and explosions at other locations.

There are also 3 reactors that need to continue to be cooled. This could turn into one more serous situation. So far it has been contained. There is pretty much 0% chance that any radioactive issues could reach California, even in the worst foreseeable situations.

This is how I have been sharing news via my web channels...
This is my morning video on the subject.

quote Originally posted by Butter: You are wise my friend. Your words have merit.

Thanks!

[This message has been edited by Wudman (edited 03-14-2011).]

The worldwide average background dose for a human being is about 2.4 millisievert (mSv) per year.

quote Originally posted by phonedawgz: Yes the reactors shut down right after the quake. It takes time for the reactions to subside. During that time the excess heat needs to be dissipated or the core will overheat and the tube that hold the fuel will melt. I see the problem in expecting the power plants are not going to have issues. Tens of thousands of people died and entire cities have been wiped out. There have been serious fires and explosions at other locations. There are also 3 reactors that need to continue to be cooled. This could turn into one more serous situation. So far it has been contained. There is pretty much 0% chance that any radioactive issues could reach California, even in the worst foreseeable situations.

Not exactly true, chernobyl spread radiation around the world. It just depends on how much reaches cali. I doubt more than background levels. If they have 3 complete meltdowns, I wouldn't want to make that bet though.

And it's not foreseeable that these boiling water reactors will somehow change into graphite reactors.

Totally different design.

That has zero to do with anything. Graphite vs boiling water. If the reactor core melts through the containment vessel, which it will if it continues to over heat you will have full meltdown. Gamma fallout will be in the atmosphere.

Graphite burns. Burning graphite mixed with a melted radioactive core launches radioactive particles into the atmosphere. Last I checked water doesn't burn.

This reactors core is located inside a containment vessel. The core could melt and there still could not be the release of radioactive particles.

[This message has been edited by phonedawgz (edited 03-14-2011).]

quote Originally posted by FieroRumor: There comes a point where the saferty features can overcomplicate a design, maybe even prevent the dang machine from workin'...like when sensors that detect something break down and fail...

What I see is that it is impossible to design for every possible scenario, if for no other reason than it is impossible to predict every possible scenario. Once the point comes where that is finally realized, then the decision to be made is whether or not it is wise to continue down a path where a single point failure (and by point I mean in a geographical sense, not a technological sense) can have global and long-lasting consequences.

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Bring back civility and decorum!

It's possible to understand someone's point of view without accepting it. It's possible to disagree with someone without being rude and nasty about it. Sure it's hard, but nothing worth doing is ever easy, is it?

Its not really this complicated, the core on some of the reactors are damaged the only thing stopping the radioactive material from escaping into the atmosphere is the containment vessel, Without stopping the reactions completely the reaction will get hot enough to breach the containment vessel also, like it did the core. It doesn't matter that graphite burns, the graphite reacted with the atmosphere and burned.

The soviet unions problem was they no containment vessel over the reactor so once the core was breached gamma radation was exposed to the outside world. Containment vessels only buy you time. If you don't cool the core down faster than its heating up and
shut down the reaction you are back at chernobyl. The only difference is it might like an explosion to help scatter the radio active material into the upper atmosphere and thats a maybe.

You don't 'stop the reaction completely'. Nuclear decay will continue on for a very very long time. Spent fuel rods are stored in pools in power plants all across the US. They give off heat. They don't melt down.

quote Without stopping the reactions completely the reaction will get hot enough to breach the containment vessel also, like it did the core.

is without merit

quote It doesn't matter that graphite burns, the graphite reacted with the atmosphere and burned.

shows you have no clue of what happened at Chernobyl.

quote The soviet unions problem was they no containment vessel over the reactor so once the core was breached gamma radation was exposed to the outside world.

There were a lot more problems with the reactor at Chernobyl that that. A LOT more.

quote Containment vessels only buy you time. If you don't cool the core down faster than its heating up and shut down the reaction you are back at chernobyl. The only difference is it might like an explosion to help scatter the radio active material into the upper atmosphere and thats a maybe.

incorrect

Here are two blogs that give a very good detailed explanation of what is going on which may help us to better understand.

Situation at Fukushima nuclear power station
http://wordpress.mrreid.org...clear-power-station/

Nuclear energy 101: Inside the "black box" of power plants
http://www.boingboing.net/2...ar-energy-insid.html

quote Originally posted by dennis_6: Its not really this complicated, the core on some of the reactors are damaged the only thing stopping the radioactive material from escaping into the atmosphere is the containment vessel, Without stopping the reactions completely the reaction will get hot enough to breach the containment vessel also, like it did the core. It doesn't matter that graphite burns, the graphite reacted with the atmosphere and burned. The soviet unions problem was they no containment vessel over the reactor so once the core was breached gamma radation was exposed to the outside world. Containment vessels only buy you time. If you don't cool the core down faster than its heating up and shut down the reaction you are back at chernobyl. The only difference is it might like an explosion to help scatter the radio active material into the upper atmosphere and thats a maybe.

In Chernobyl the water in the core (water was the heat transfer medium and primary coolant, just like in a boiling water reactor or most other reactors) was heated enough to break it into hydrogen and oxygen. This perfectly combustible mixture ignited and the resultant explosion was enough to blow the several tens of tons lid off the reactor chamber. The explosion also pushed the core down and collapsed several floors of the basement complex underneath the reactor. At this point the core melted down extremely fast and became liquid. The only thing that saved the world from an even worse radiological disaster was that the walls of the core were filled with boron sand as a neutron absorbing shield. This sand flowed out of the ruptures at the bottom of the core wall caused when the basement levels pancaked and mixed with the molten uranium, dampening it just enough to cool back into a solid state. If it had melted down into the water table the resultant steam explosion would launched hundred of tons of extremely radioactive material into the atmosphere and increased the worldwide radiational aftereffects by an order of magnitude.

Hard to believe that one nuclear power plant on one itsy bitsy patch of earth could have that big of an effect world wide for so long. Several hundred square miles are still considered uninhabitable.

And it wasn't even their first nuclear accident: http://en.wikipedia.org/wiki/Kyshtym_Disaster (rated number two, behind Chernobyl)
That entire region is in pretty bad shape: http://en.wikipedia.org/wiki/Mayak

Be interesting to see where the Japanese nuclear disaster falls on the scale.
http://en.wikipedia.org/wik...Nuclear_Events_Scale


------------------
Bring back civility and decorum!

It's possible to understand someone's point of view without accepting it. It's possible to disagree with someone without being rude and nasty about it. Sure it's hard, but nothing worth doing is ever easy, is it?

[This message has been edited by JazzMan (edited 03-14-2011).]

quote Originally posted by phonedawgz: You don't 'stop the reaction completely'. Nuclear decay will continue on for a very very long time. Spent fuel rods are stored in pools in power plants all across the US. They give off heat. They don't melt down. [QUOTE]Without stopping the reactions completely the reaction will get hot enough to breach the containment vessel also, like it did the core.

is without merit

quote It doesn't matter that graphite burns, the graphite reacted with the atmosphere and burned.

shows you have no clue of what happened at Chernobyl.

quote The soviet unions problem was they no containment vessel over the reactor so once the core was breached gamma radation was exposed to the outside world.

There were a lot more problems with the reactor at Chernobyl that that. A LOT more.

quote Containment vessels only buy you time. If you don't cool the core down faster than its heating up and shut down the reaction you are back at chernobyl. The only difference is it might like an explosion to help scatter the radio active material into the upper atmosphere and thats a maybe.

incorrect [/QUOTE]


I will try and explain this very simply for you.
Imagine a cup within the cup
The inner cup is the core
the radioactive material is inside the cup
The outer cup is the containment vessel

According the Japanese its possible the inner cup is breached, and the outer cup is containing the radioactive material.
THEY ARE STILL HAVING TO COOL THE CORE!!!! If the outer cup "containment vessel" was impenetrable it would be over!!!!!

Jazzman - Wikipedia has quite a different set of events that occurred at Chernobyl

http://en.wikipedia.org/wiki/Chernobyl_disaster

[This message has been edited by phonedawgz (edited 03-14-2011).]

Chernobyl, had a core breach and no containment vessel.
Japan has a core breach with a containment vessel.

Chernobyl had a graphite reactor which burned and didn't help matters any, but is null and void if the reaction temps in Japan exceed what the containment vessel can stand. Which if they can't keep saltwater pumped in the reactor at the correct rate will happen.
I believe 2500 degrees is what they said the vessels breaking point is.

Boron will shut down the nuclear reaction thats why it is being mixed with salt water. Thats what I am speaking about when I say stopping the reaction, They said it will take days to weeks for that to have an effect. Don't believe everything CNN tells you. We didn't have a graphite reactor at 3 mile island and we were worried about a melt down. How could that be without a graphite reactor and having a containment vessel? How come they still need to cool the reactors if the containment vessel is end game? Just concrete over them and call it a day.

You're still way off.

We did have core damage at TMI (melted core)

No it can't just be concreted over.

No I don't consider a containment vessel Godzilla proof. Not Rodan proof either.

quote Originally posted by phonedawgz: You're still way off. We did have core damage at TMI (melted core) No it can't just be concreted over.

I just said it didn't have a graphite core, and it had a containment vessel.
If it lacked a containment vessel at that point it would have resembled chernobyl, if they didn't cool it down before it breached the vessel it would have resembled chernoybl. I don't know why your so hung up on the damn graphite.

I'm not understanding something here, and I am afraid I may sound stupid here, so bear with me.

Doesn't the Nuclear plant produce electricity?

How can the pumps stop getting electricity from a plant that they are in?

Brad

http://www.dailymail.co.uk/...s-nuclear-plant.html

quote Originally posted by twofatguys: I'm not understanding something here, and I am afraid I may sound stupid here, so bear with me. Doesn't the Nuclear plant produce electricity? How can the pumps stop getting electricity from a plant that they are in? Brad

Brad,
The power generations was automatically shut down because of earthquake safety protocols. There were diesel generators that were either disabled by the tsunami or just failed. Battery power was only good for 8 hours and they supplemented those batteries, but that did hot provide adequate cooling.

That last article is pretty damn, damming about the situation. It doesn't really matter locally if those are not the trusty old Chernobyl style plants. Three reactors melting down and a wind change coming that will blow stuff inland?

quote Originally posted by Wudman: Brad, The power generations was automatically shut down because of earthquake safety protocols. There were diesel generators that were either disabled by the tsunami or just failed. Battery power was only good for 8 hours and they supplemented those batteries, but that did hot provide adequate cooling. That last article is pretty damn, damming about the situation. It doesn't really matter locally if those are not the trusty old Chernobyl style plants. Three reactors melting down and a wind change coming that will blow stuff inland?

Also depends how much of the fallout is ejected into the atmosphere if the containment vessels fail as to how much radiation California and the western states would see. I wouldn't expect more than slightly elevated background levels, but if multiple reactors meltdown birth defects and cancer could be a concern. That would be absolute worse case and not very likely IMHO.

There is a risk that molten nuclear fuel can melt through the reactor's safety barriers and cause a serious radiation leak.

THIS IS WHAT I WAS TALKING ABOUT, but remember I am dead wrong, lol
"There is a risk that molten nuclear fuel can melt through the reactor's safety barriers and cause a serious radiation leak."
http://www.dailymail.co.uk/...s-nuclear-plant.html

[This message has been edited by dennis_6 (edited 03-14-2011).]

quote Originally posted by phonedawgz: Jazzman - Wikipedia has quite a different set of events that occurred at Chernobyl http://en.wikipedia.org/wiki/Chernobyl_disaster

I see some newer info has been published since the last time I looked into this. My main info was a lengthy documentary following Russian scientists exploring the reactor looking for the fuel. It was felt very important to know where it went since it wasn't in the reactor anymore for the most part. The Russian scientists along with the documentary producers described the way the boron sand mixed with fuel (and apparently concrete as well) to fuse into the blob, one part of which a scientist referred to as an "elephant's foot". I'm updating my personal knowledge to reflect that it was a steam explosion (though probably some hydrogen was involved, at those temperatures it's not possible for it not to be) but keeping the bit about the boron sand since that came right from the Russians and the wiki doesn't clarify that point. At that time there was no mention of a criticality event, that's news to me.

Hard to imagine things could have been far, far worse in the worst nuclear disaster this world's ever seen. I can hardly wait until fail-proof nuclear plants are designed and built so another nuclear accident can never happen again.

------------------
Bring back civility and decorum!

It's possible to understand someone's point of view without accepting it. It's possible to disagree with someone without being rude and nasty about it. Sure it's hard, but nothing worth doing is ever easy, is it?

quote Originally posted by JazzMan: I'd settle for one that was terrorist-proof, human stupidity-proof, and perfect in any way that can be or will ever be measured. That second of the three will be the hardest.

The second of the three is impossible.

Brad - So after fully inserting the control rods in the reactor it takes some time for the reactions to slow down and for the core to cool. The initial power drop is quick but remember a reactor that puts out 1.5mW in electricity actually puts out 4.5 mW in heat. Bring that down by 95% and you are still kicking out a huge amount of heat. The cooling systems need to stay online during this time. At Point Beach power plant here in Wisconsin we could use power from the grid, power from generators (diesel generators started by compressed air) and batteries to circulate cooling water. btw, some here seem to think you 'fill' the core with water. What you do is circulate water much like an engine in your car.

An exposed core will overheat and melt. The fuel rods that hold the fuel can melt. That melted metal of course would collect in the bottom of the reactor. No that pool of metal would not start producing more power because it's a single mass. The residual heat production would continue however. Will it melt through the containment vessel? Most likely not, Will it 'burn' as stated earlier in this thread? No. Will it be transported into the atmosphere via burning graphite as in Chernobyl? Nope - no graphite. Can it be used by Rodan to incapacitate Godzilla - Yes.

From that last link, a throwaway line buried deep in the article: It also emerged yesterday that the government ignored explicit warnings from a Japanese expert on nuclear power more than three years ago.

Professor Ishibashi Katsuhiko, of Kobe University, said the guidelines introduced to protect the nuclear plants were ‘seriously flawed’ and that the plants were vulnerable to major quakes.

‘Unless radical steps are taken now to reduce the vulnerability of nuclear power plants to earthquakes, Japan could experience a true nuclear catastrophe in the near future,’ he warned in 2007.



Hmmm...Just a coincidence I'm sure...

[This message has been edited by JazzMan (edited 03-14-2011).]

quote Originally posted by phonedawgz: Brad - So after fully inserting the control rods in the reactor it takes some time for the reactions to slow down and for the core to cool. The initial power drop is quick but remember a reactor that puts out 1.5mW in electricity actually puts out 4.5 mW in heat. Bring that down by 95% and you are still kicking out a huge amount of heat. The cooling systems need to stay online during this time. At Point Beach power plant here in Wisconsin we could use power from the grid, power from generators (diesel generators started by compressed air) and batteries to circulate cooling water. btw, some here seem to think you 'fill' the core with water. What you do is circulate water much like an engine in your car. An exposed core will overheat and melt. The fuel rods that hold the fuel can melt. That melted metal of course would collect in the bottom of the reactor. No that pool of metal would not start producing more power because it's a single mass. The residual heat production would continue however. Will it melt through the containment vessel? Most likely not, Will it 'burn' as stated earlier in this thread? No. Will it be transported into the atmosphere via burning graphite as in Chernobyl? Nope - no graphite. Can it be used by Rodan to incapacitate Godzilla - Yes.

More magical containment vessels, huh?
Also not seeing burning fuel rods anywhere, burning graphite yes, fuel rods no.
Article seems to state it can burn through containment vessel
Doesn't require graphite to be transported to atmosphere, we are talking superheated goo coming in contact with moisture and other non superheated objects. Can you say exactly what will happen and oh yeah, show the accepted models and examples of what has happened before. lol

[This message has been edited by dennis_6 (edited 03-14-2011).]

I guess it must seem magical to someone who thinks the core is like a cup.

quote Originally posted by JazzMan: I'd settle for one that was terrorist-proof, human stupidity-proof, and perfect in any way that can be or will ever be measured. That second of the three will be the hardest.

Especially human stupidity-proof. It is to be remembered, that Chernobyl happened because of mistakes made during an intentional planned test.

And IIRC, addittional sand was brought in and dumped on the burning core via helo.

[This message has been edited by maryjane (edited 03-14-2011).]

quote Originally posted by phonedawgz: I guess it must seem magical to someone who thinks the core is like a cup.

Cup is analogy for people who can't understand a containment vessel can not stand excessive temps. I know the core isn't open ended, i know it doesn't hold standing water and requires a constant flow, and I know it contains fuel and control rods. I also know that the goo that can melt through the core and can melt through the containment vessel and the concrete of the building, and any damn thing it touches till it cools. This is where you seem to lack understanding. Now tell me what happens when this radioactive superheated goo comes in contact with mositure? I mean we have thousands of recording incidents for you to draw your knowledge on right? I am sure everybody knows its just harmless and will just cool and be concreted over once it cools.
Zero chance something superheated could react with moisture and eject radioactive particles into the atmosphere, and there most certainly won't be contaminated soil to get blown by the wind.

CNN said it can't happen, and they would know. They are staffed by experts in nuclear science. Yeah, thats the ticket. I am so glad your here to rehash cnn. Thanx.

Look up thermal runaway.

[This message has been edited by dennis_6 (edited 03-14-2011).]

quote Originally posted by dennis_6: More magical containment vessels, huh? Also not seeing burning fuel rods anywhere, burning graphite yes, fuel rods no. Article seems to state it can burn through containment vessel Doesn't require graphite to be transported to atmosphere, we are talking superheated goo coming in contact with moisture and other non superheated objects. Can you say exactly what will happen and oh yeah, show the accepted models and examples of what has happened before. lol

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