a reply to: scraedtosleep
The Fukushima plants were poorly designed. They were of the BWR instead of the PWR design, eliminating one barrier to radiation leakage, they were not
designed to withstand seismic events to the degree plants in the US are, and no allowance was made for rising water levels.
The earthquake damaged the plants and a SCRAM (Safety Control Rods Activation Mechanism) was initiated as designed. Unlike most systems we are
familiar with, a nuclear reactor is always "on" by default once the fuel pellets are loaded; the only way to turn it "off" is by the insertion of the
control rods. The control rods fit inside the tubes of nuclear fuel at extremely tight tolerances and serve to absorb free neutron radiation (alpha
particles) and thus stop or slow the chain reaction.
The control rods require power to insert, so there are three back-up sources of power (obviously one cannot get power from a plant under shutdown).
First is the electrical grid itself, which can be used bi-directionally. Second are the diesel generators, huge diesel engines hooked to huge
generators with fuel tanks that are always kept full for emergencies. Third are the batteries which are maintained on site and typically hold just
enough energy to shut down the plant if there are no problems during the SCRAM.
The earthquake at Fukushima damaged the power grid so the diesel generators kicked on automatically. At this point there was no danger. The tsunami,
however, flooded the fuel tanks, which were built far too low in elevation, and contaminated the fuel and made the diesel generators stop. That left
the batteries. Delays in accessing the plant due to roads being impassable, combined with slow responses from TEPCO delayed the deployment of external
generators until past the 10-hour limit, and the damage to the plant was severe enough to delay the SCRAM.
The result was that the plant went without power before the SCRAM was complete. As a result, the reactors overheated and warped the control rods,
making it impossible to insert them once power was regained. All four reactor cores then went into full meltdown and are, at present, sitting in the
bedrock below Fukushima, where they will remain radioactive for a few million years. How close they are to the Pacific and how much radiation is
escaping that magma-filled tomb are questions that are open for debate.
In the US, newer plants are PWR design (although there are some older BWR plants still operating). Seismic design (which is the section I worked in)
Is based on two orders of magnitude above the last earthquake in 100 years, and the last 120 or so years is actually considered when possible. Diesel
generator design is more tightly regulated than Japan at the time, and the chances of contaminated fuel are much, much lower. The military, not the
power plant owner, would take over operations should a plant get to the batteries stage and have any problems, so corporate interests would be ignored
at that point.
The NRC (Nuclear Regulatory Commission) in the US is extremely powerful and extremely dedicated to safety. The plant near me is not operating and will
never operate because of that fact; the NRC found enough errors during construction to make them watch the last part of the construction so tightly
the cost became prohibitive. No nuclear plant in the US gets a pass from these people; a planned visit from the NRC created an absolute "no mistakes
or else" atmosphere that I saw get many people fired on the spot for minor safety violations. The short time I worked in the Power Production Division
(which verifies/tests completed systems and turns them over to the operations division), I was in contact with NRC officials quite often. They do not
have a sense of humor. Compared to these people, the IRS are comedians.
What you suggest is beyond the level of remotely possible in the US.