Because I found it extemely useful, I'm re-printing in full Galrahn's latest post at Information Dissemination about the ongoing nuclear crisis in Japan surrounding the Fukushima nuclear power facility in Japan, that nation's oldest nuclear site:
There is a lot of hype and even some stupid nonsense being thrown around in the media about the nuclear situation at Fukushima. If you don't understand nuclear power, seek out discussions on the topic from the retired Navy communities, many of whom work on civilian reactors today and are discussing this issue in numerous places all over the web. A good place to start is the comments of this post at Bubblehead. Also see Dr. Josef Oehmen's comments here, a very useful read for context and perspective.
A few details that folks might want to note:
The reactors that are being discussed in the news were successfully shut down. The problems are related to post shutdown safety.
People who compare Fukushima and Chernobyl don't know anything about Fukushima or Chernobyl. This is like comparing the safety, survivability, and resilience of row boats and battleships. Everything that made Chernobyl a disaster - lack of safety, redundancy, etc.. - is what is making Fukushima a successful containment of a serious problem.
This event in Japan is the worst case scenario. First you have a 9.0 earthquake, then you have this massive tsunami, then you have the freezing weather that compounds your water problems. In the case of Fukushima the earthquake knocked out the power, forcing them to move to generators. The tsunami came along and knocked out the generators, forcing them to move to battery power.
The battery power has very limited life, somewhere between 8-24 hours, and we are somewhere north of 54 hours on battery power now at the nuclear plants. Obviously that creates a serious problem with these old reactors that require electricity for cooling. BTW, worth noting, the new nuke tech does not require electricity to cool.
Observing that this is the worst case scenario and that Fukushima is Japans oldest nuclear power plant; worth highlighting that there is still no evidence that there has been loss of containment or a leak that represents a public health concern. The leaks to date have been controlled and regulated as part of the safety procedures. Keep your head on folks, all of the public safety being done from iodine to evacuations is part of the stated Japanese nuclear safety plan which can be found online (I have not seen an English version).
The Fukushima plant situation is serious, but it is not some emerging catastrophe some are making it out to be.
Good points, all. The extensive (and well-worded for the layman, such as yours truly) response by M.I.T's Dr. Josef Oehmen was absolutely phenomenal!