Uploaded March 2011 | Updated September 2026, 2 hours ago
HYPOTHESIS FROM A NUCLEAR INDUSTRY SOURCE:
During the earthquake and loss of all AC power, the plant went into emergency shutdown mode just as designed. The diesel generators automatically started just as they were designed to do and they began to power the cooling pumps. Then the tidal wave struck, taking out the diesel generators and doing extensive damage to the steam plant, some of which may have been underground in the form of a watertight basement. This would have also taken out the next chain in the emergency backup systems by damaging the steam operated injection pumps, and possibly putting them underwater in what might now be a giant pipe filled swimming pool.
With no way to inject cooling water, then the water around the core would begin to boil, the pressure would rise but the relief valves would open automatically lowering the plant pressure. But in doing so the plant would start losing water that could no longer be injected back into the plant. After a few hours this would begin to uncover the core and the radiation levels around the site would start to increase dramatically. The fuel rods would now begin to over heat and there would be the threat of melting the tubes that hold the fuel pellets and provide the first barrier against radioactive contamination. So in order to prevent uncovering the core any further the operators probably manually shut off the relief valves and began trying to control the pressure slowly by manual manipulation of the valves, they would allow the pressure to rise to the maximum plant limit in order to cause as much of the steam as possible to turn back into water. and keep the core covered while they desperately worked to restore some power.
The fact that an explosion occurred tells me that they lost the battle and that the plant suffered either a steam explosion or a hydrogen explosion, either of which are very bad news for everyone concerned. The reactor now will be all or mostly uncovered by water, which means that serious damage and releases of radiation are occurring. The next level of containment is the bottom of the reactor vessel, if the fuel burns through that then it will fall to the floor of the containment building and begin to burn through several feet of reinforced concrete. And all of this time it will be releasing deadly clouds of radioactive particles.
If it manages to burn through the containment building then it will hit groundwater producing a violent reaction as the cold water makes contact with the hot fuel pellets, more radioactive steam and particulates will be produced. My guess is that the fuel will not escape the containment vessel though, but if it does then it will not go though the floor, I believe that they will fly tankers over the remains of the building and dump water until the heat has dissipated. This will work as long as the fuel does not gather together and form a critical mass, if it does that, then it will burn until it has exhausted itself and putting regular water on it will just make it burn hotter.
There is also the issue of the fuel rods in the spent fuel pool. These spent fuel rods also need continuous cooling water circulation. It would take them longer to boil off the water that was covering them originally, but when they do and they become uncovered, then they too will begin to melt. It is this scenario that is extremely frightening. The amount of radiation that this spent fuel is capable of producing is astronomical! The result of a meltdown would not be like a nuclear bomb, but rather more like a slow but continuous dirty bomb that could render Japan and other nearby areas uninhabitable.
HYPOTHESIS FROM A NUCLEAR INDUSTRY SOURCE:
During the earthquake and loss of all AC power, the plant went into emergency shutdown mode just as designed. The diesel generators automatically started just as they were designed to do and they began to power the cooling pumps. Then the tidal wave struck, taking out the diesel generators and doing extensive damage to the steam plant, some of which may have been underground in the form of a watertight basement. This would have also taken out the next chain in the emergency backup systems by damaging the steam operated injection pumps, and possibly putting them underwater in what might now be a giant pipe filled swimming pool.
With no way to inject cooling water, then the water around the core would begin to boil, the pressure would rise but the relief valves would open automatically lowering the plant pressure. But in doing so the plant would start losing water that could no longer be injected back into the plant. After a few hours this would begin to uncover the core and the radiation levels around the site would start to increase dramatically. The fuel rods would now begin to over heat and there would be the threat of melting the tubes that hold the fuel pellets and provide the first barrier against radioactive contamination. So in order to prevent uncovering the core any further the operators probably manually shut off the relief valves and began trying to control the pressure slowly by manual manipulation of the valves, they would allow the pressure to rise to the maximum plant limit in order to cause as much of the steam as possible to turn back into water. and keep the core covered while they desperately worked to restore some power.
The fact that an explosion occurred tells me that they lost the battle and that the plant suffered either a steam explosion or a hydrogen explosion, either of which are very bad news for everyone concerned. The reactor now will be all or mostly uncovered by water, which means that serious damage and releases of radiation are occurring. The next level of containment is the bottom of the reactor vessel, if the fuel burns through that then it will fall to the floor of the containment building and begin to burn through several feet of reinforced concrete. And all of this time it will be releasing deadly clouds of radioactive particles.
If it manages to burn through the containment building then it will hit groundwater producing a violent reaction as the cold water makes contact with the hot fuel pellets, more radioactive steam and particulates will be produced. My guess is that the fuel will not escape the containment vessel though, but if it does then it will not go though the floor, I believe that they will fly tankers over the remains of the building and dump water until the heat has dissipated. This will work as long as the fuel does not gather together and form a critical mass, if it does that, then it will burn until it has exhausted itself and putting regular water on it will just make it burn hotter.
There is also the issue of the fuel rods in the spent fuel pool. These spent fuel rods also need continuous cooling water circulation. It would take them longer to boil off the water that was covering them originally, but when they do and they become uncovered, then they too will begin to melt. It is this scenario that is extremely frightening. The amount of radiation that this spent fuel is capable of producing is astronomical! The result of a meltdown would not be like a nuclear bomb, but rather more like a slow but continuous dirty bomb that could render Japan and other nearby areas uninhabitable.
