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Jim 0216 :" I absolutely do not trust nuclear power plants because man hasn’t yet shown he really knows what he’s dealing with."

I have several issues of concern about Fukushima
It was built on a known fault line , close to the ocean (for cooling purposes), apparently with disregard fro Tsunami .
After the disaster happened, I was wondering why they kept pouring water onto the roof; it seems that is where they stored the 'spent fuel rods' that were less powerful
in what they call a 'cooling pool', for pre-warming the water which would be sent into the reactor vessel which would later become steam for turbine generation of electricity.
Why would anybody store a cooling pool above the reactor, elevated some three floors up over the nuclear reactor vessel ?
Based on the information today, it would appear that even robots which are designed to withstand radiation, cannot withstand this level radiation for longer than 2 hours.

Actually, the problem started when the designers of the plant decided to place the emergency generators to power a shutdown scenerio at a location near sea level.

If they had been smart, the gensets would have been sited on the bluff above the plant, and emergency power would have kicked in within seconds, to shut down the plant. Once the gensets we’re flooded, it was all over!

Exact thing that caused Katrina floods to overcome the emergency pumps.

The spent pool is located above the reactor vessel. During refueling, they open the vessel and remove the spent bundle. This is all done underwater so the spent rods, which are highly radioactive, are never exposed to the atmosphere. Once adequately “cooled” they are transferred out of the pool into large casks and moved to a new location.

Here in the US those rods that are in the casks were to be transferred to Yucca Mountain for permanent storage but that contract has been broken by Obama and Harry Reid. Of course Harry didn’t have any problem with spending billions on Yucca until the time came to open it up for it’s intended use.

The fault line, near the ocean build, and design assumptions regarding the potential for tidal waves are legitimate concerns. The pool on the refueling floor is called a spent fuel pool. Used fuel from refueling is stored there. The initial design was to store the fuel for about five years then reprocess it. Except for refueling spent fuel pool water does not communicate with the reactor. Spent fuel pool water is not used to make steam to make electricity. The location simplifies refueling. The pool is fully seismic and is designed so that it cannot drain below the level of required shielding above the spent fuel. IMHO they may have been able to save the reactors equipped with RCIC turbines by thinking way outside of the box. It would have been risky and would have required cutting the RCIC turbine exhaust line and routing the exhaust out of the reactor building. Do-able but dangerous. All BWR RCIC turbine exhaust lines should have the ability to exhaust to the atmosphere added to their normal exhaust path.