Dummies Guide to Nuclear Plant Accidents

This is much of what I thought already.   Perhaps the point that they don't dwell on in this PDF is that what is trying to be controlled is a nuclear reaction- this is the normal day to day operation.  Once you get the thing going, it doesn't want to stop all on it's own, especially if you reduce the necessary cooling which it wants continously.   It is a reaction underway.   It will melt through the massive steel Reactor Vessel, in a matter of hours if out of control. 

Dummies Guide to Nuclear Accidents

There are "Control Rods" that are used to control the rate of the nuclear reaction, and in theory, if they are inserted all the way into the uranium rod bundles, they will stop the reaction completely.  However, without cooling water flowing during this shutdown process it won't shutdown.  

http://science.howstuffworks.com/nuclear-power3.htm

And here is a pretty cool video from CNN.

http://www.cnn.com/video/#/video/world/2011/03/14/dnt.japan.reactor.explainer.nhk?hpt=C2

You know, these plants are always right by the water, and there are tall structures everywhere.   Why not put the diesel generators that drive the cooling water pumps on the roof?    Seems like a no-brainer actually.    Hmmm...earthquake....tsunami, they go hand in hand.   What is the extra cost involved in putting the diesel generators out of harms way?

And how about a final backup plan....big pumps powered by diesel directly, capable of pumping enough water to fill the entire reactor building, even if there is a 2' hole in the building, and keep it full enough that the reaction shuts down before the diesel tank runs dry.   

For the future, think and research on Thorium, a better way than uranium.   Safer, more abundant.