Japans Tschernobyl: I would live a zone of 200 km
 

In German media [1] you can read, that it will be quite sure, that the nuclear station will explode an countermines a big zone like Tschnobyl. I would live a zone of minimum 200 km around the reactor Fukushima I.

[1] Havarie an Japans Akws Fukushima I + II: Kühlung von 6 Reaktoren ausgefallen - taz.de

reactors
 

As pointed out in other thread, Chernobyl reactor of RBMK-type has another design than Fukushima one. RBMK wasn't in hard containment.

quote :

On 26 April 1986, at 01:23 a.m. (UTC+3), reactor four suffered a catastrophic power increase, leading to explosions in the core. This dispersed large quantities of radioactive fuel and core materials into the atmosphere[6]:73 and ignited the combustible graphite moderator. The burning graphite moderator increased the emission of radioactive particles, carried by the smoke, as the reactor had not been contained by any kind of hard containment vessel (unlike all Western plants). The accident occurred during an experiment scheduled to test a potential safety emergency core cooling feature, which took place during the normal shutdown procedure.

Chernobyl disaster

With a nuclear meltdown it won't matter what kind of containment you have. Eventually the vessel will fail. Right now the seawater being poured is only buying time but it will destroy what remains of any machinery required to provide a constant cooling medium to the core.

Unless a way can be found to provide desalinized cooling water, a melt down of the core is all but inevitable.

meltdown
 

With a containment you can prevent Chernobyl-like explosion of reactor. Meltdown inside core takes place everytime when cooling system is broken.

Yes, the meltdown may not be preventable but how it's contained can restrict the outside damage considerably. This core was built with that in mind. The Russian one wasn't because it was built dureing Stalinist era and safety considerations for the local plebes wasn't high on the "to do" list.

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I have to find a way to help get my friends out of Japan as soon as possible. Most networks including C-span the biggest international non spin network say that the meltdown could result in an explosion of the plant! that could mean a nuclear explosion. i don't want my friends stuck there if that happens!

It's not going to be a nuclear explosion like a Nuclear bomb. There would be a hydrogen explosion that would blow the outer cement structure off. It will have radioactive elements in it yes, but not like a actual thermonuclear weapon. It's called "weapons grade uranium or plutonium" because it takes a certain purity level and a certain amount to make such a huge reaction.

A meltdown can contaimnate a large area but it's a different type of destruction...Radiation posioning is what would result. Not saying that's not seriously bad, just trying to differentiate what they mean by "explosion" here.

This might help those on the West Coast of N. America:

NRC: Home Page

I live in Ukraine, and also watching the situation in Japan, I hope that everything will cost, good luck to you!