Know nukes

The first semester of my Senior year at Denison University, I participated in an off-campus research program at Oak Ridge National Laboratory.  Oak Ridge is a government research facility that was built outside of Knoxville, TN, to develop nuclear weapons capabilities as part of the Manhattan Project.  The central research facilities are in the middle of a 34,000 acre reserve.  Originally, this was a secure, top secret area.
(By the way, I was there doing robotics research, not building weapons.  My building was "outside the gate".  I didn't even have to pass through any security checkpoints to get to my workplace.)
The Fall that I was there was the first time in 40 years that they opened up the reservation for deer hunting.  Vehicle-deer accidents were averaging one every 1-2 days.  Given the length of time that the deer population had been living unperturbed there, the local hunters were extremely excited at the possibilities of bagging some big bucks for trophies.
As the day approached, all the workers around the lab were getting more and more excited.  The local newspaper was full of articles about the hunt.  The official rules from the lab were published.  Normal limits on the number of deer that could be taken would be in effect.  The only special rule was that each deer killed had to be taken to a special checkpoint before it was removed from the reservation to check the body for radiation.
I used to tell that story, and I thought that the final punchline was pretty funny.  After what is happening right this moment in Japan, I'm not laughing about it anymore.
When I was at Oak Ridge, I listened to presentations by scientists who were developing new ways to store nuclear waste in deep mines encased in concrete.  They were calculating the probability of any of the radiation seeping into the groundwater.  These were really smart people working to solve a difficult problem.  I think they have some good solutions for this problem.  For years I've been generally pro-nuclear.   While I understand there are some environmental, security, and political issues surrounding the tasks of acquiring the uranium, transporting it, refining it, and storing the waste, I felt that those costs were justified given the value of the energy produced.
What the current Japanese nuclear disaster has reminded me of is the risk.  The risk of an accident is too high.  Let me take a moment to review the definition of risk, just to be clear about what I mean.  Risk is the probability of something happening multiplied by the cost if it does happen.  Normally, we think of risk only with respect to the probability.  If something only has a 0.00001% chance of happening, we say it has a low risk.  But if something has a 50% chance of happening, but the cost that we have if it does is low, then that also has a low risk.
For nuclear energy, the cost of an accident is extremely high.  There is, obviously, the immediate danger to the people who are directly exposed during the crisis, but there is also long-term consequences of having radiation released into the environment.  One figure I read said that the radioactive plutonium that is created by nuclear power plants will be around for the next 12,000 generations.    It will be a danger to people for a longer time than there have actually been a species on this planet that we can call "people" (or at least modern humans).  The cesium-137 that was released will be around in dangerous quantities for hundreds of years.   So even if the probability of an accident is low, the cost is so high that almost any probability other than zero makes the risk high.  And in the case of nuclear energy, the probability isn't so low.  There have been at least four major nuclear accidents in the 70 years that we've had nuclear energy.   They happen, and people die.  For decades.
So I'm not laughing at jokes about nuclear deer anymore.   On the other hand, I'm not panicking and taking prophylactic iodine tablets.  The radioactive iodine isn't an immediate threat to us, and after a few months it will have decayed to a point that it isn't a problem.  What I am doing is thinking more about how we really need to be serious about "clean" energy.  We need to understand the risks of our sources of energy and choose wisely.  And mostly, we need to reduce our overall energy consumption so we aren't so desperate for energy that we'll take it from any source, no matter what the risk.