Update on the Japanese Situation

Likely Final Update for a While:
At this point it has become difficult to sift reality from fantasy as the various media outlets have taken the information they want, parsed them together how they like, and then presented them as the doomsday of all nuclear power…at least the bad ones.
In total there were two emergencies declared. The one at the Fukushima plant and another emergency declared at another plant down the road at Onagawa. The Onagawa plant emergency was declared due to raising radiation levels around the plant, but not due to in-ability to cool the nuclear core.
Fukushima unit 1 is the plant in the worst state. The basic timeline is thus: The earthquake and tsunami hit. This damaged the electrical grid, the emergency backup diesel generators, and the backup, non-electrically dependent, core cooling system, BUT not the actual main core cooling system. Backup batteries were still up and running and core cooling was maintained for the 6-8 hours that the batteries were running. During that time emergency agencies scrambled to get power backup and running or some other system working. Eventually the water started to boil and the fuel began to melt, the phase change in the water and fuel stalled the heat buildup for a time. The emergency agencies managed to get seawater mixed with boron to pump into the reactor vessel. Around this time there was a hydrogen buildup in the reactor building, outside the containment walls, some say due to hydrogen released by damaged fuel, I say hydrogen released from other damaged system…it’s probably both. The hydrogen buildup resulted in an explosion that blew the roof off of the building surrounding the containment structure. After that time radiation levels began to decrease. At this time radiation levels are still low and we are over the residual heat curve. The likelihood of core damage is high, but it is very difficult to determine the extent of the condition and will likely be unknown until they are able to take the reactor apart.
Fukushima unit 3 is now undergoing the same problems unit 1 was undergoing. The reason for the delayed timing is likely due to less damage of the emergency systems and the design differences. Unit 3 is a newer BWR design than unit 1, which was built before the TMI accident and had many emergency systems retro-fitted into it. Unit 3 was built with the systems as part of the design.
Some things of note:
The 1000 times radiation levels: Only occurred in the control room of Fukushima unit 1, and 1000 times 0.001 is only 1 mrem, which is less than I got on a typical outage day working in the plant.
Iodine given out: This is done as a precaution and is a standard practice at all plants world-wide.
Radiation releases: Radioactive gases were released on several occasions to relieve pressure inside the plants. These releases were comparable to the radiation a person gets taking a flight from New York to Tokyo, or just living on the earth all year.
Personnel: The people running the plant now are the same guys who were there at the time of the earthquake. Seriously think about it. Who are they going to be relieved by? The rest of the city was evacuated and many, many people are still missing.