The recent 7.4 magnitude earthquake and tsunami to hit northern Japan on April 7 underscores the delicate situation at the Fukushima reactors. Although workers had to evacuate the site, preliminary reports show that damage was minimal. This time, the damaged reactors dodged the bullet. But time is not on the side of the utility as it scrambles to contain the damage. It is a race against time, with the utility trying to stabilize the situation even as the reactors degrade with time.
The basic problem was revealed by the NRC’s (Reactor Safety Team), which drafted a report that combined the collective assessment of nuclear physicists and engineers around the world. Contrary to the rosy press releases by the utility, this report revealed the true depth of the nuclear accident.
Cooling to the core of Unit 1 might be blocked by melted fuel and also by salt deposits left over from the use of sea water.
Melting in Unit 2 might have been so severe that the core actually melted through the pressure vessel, so that melted fuel dripped down to the bottom of the containment, although there is room for speculation here. This molten fuel might be the source of all the radiation leaking into the environment.
Pieces of highly radioactive fuel rods, perhaps from Unit 4, were blown over a mile from the site by the hydrogen gas explosion.
Ominously, the huge amounts of water being flushed into the containment system in a desperate attempt to cool the cores might be stressing the frame beyond its safety limit. Indeed, in case of an earthquake, it is not clear if the stressed metal of the containment, burdened with all this water, can maintain its integrity. So the very method used to stabilize the reactor (flooding the containment with huge amounts of water) may actually stress the reactor too far, esp. in case of an earthquake.
Given the fact that this international team of scientists and engineers have given us the clearest indication of the true extent of the damage, perhaps it is time for the Japanese government to remove the utility from leadership, treating them as consultants, and appointing a body of top scientists to succeed the utility.
This new international body would then be given access to the military in order to end the agony of this tragedy.