The coverage of events in Japan, especially concerning the nuclear facilities, is starting to piss me off.
No matter how low my expectations are for journalists, they still manage to fall short. I do not expect them to know everything — far from it — but do they have to know absolutely nothing?
These folks do not even know enough to ask the very simplest relevant questions. And they seem unable to find a guest “expert” who is not either a shill for the nuclear power industry or a member of Greenpeace. (Er, no offense to shills. Or to Greenpeace.)
My advice is simple: Do not listen to anybody on this topic unless you know who they are, what their credentials are, and who signs their paycheck. Which means you should stop reading me right now because I am not going to reveal any of those things.
I really am gobsmacked at the errors I am seeing. So here are some things I am pretty sure are facts, most of which have been contradicted in public by some idiot or other.
First, these reactors run on nuclear fission, not nuclear fusion, dammit. The only self-sustaining fusion reactions ever created by humanity have been measured in megatons (Pons and Fleischmann notwithstanding).
Next, the probability of a runaway chain reaction is zero. Atomic bombs are very, very hard to build. If you could make one just by shaking up a nuclear power plant, Iran would have one already. The fission reactions stopped shortly after the earthquake, when automated systems successfully shut down the reactors.
Thus far, the containment mechanisms at all of these plants are working, in the sense that nothing has escaped except the steam the operators have released. Even in the event of a “meltdown” — a weasel word with no definition, by the way — the passive containment (i.e. very thick concrete) is expected to prevent any large-scale release of radioactive material into the environment. Assuming those containment systems survived the earthquake, floods, and explosions, that is.
A Chernobyl-style failure is not possible with these reactor designs. If there is a similar outcome, it will be via a very different, and far more low-probability, mechanism.
All that said… Something nasty is entering the environment, because the zirconium-encased fuel rods are melting, releasing fission byproducts into the steam.
Definition: Two atoms are called isotopes if a physicist can tell them apart but a chemist can’t.
Definition: The half-life of a radioactive substance is how long it takes for half of a chunk of it to decay. Radioactive substances do their damage by decaying, so a short half-life implies a substance that is very dangerous but will not last long (unless there is a lot of it); a long half-life implies it will be around for a long time but is not very dangerous in the short run (unless there is a lot of it).
The isotopes to worry about are iodine-131 and cesium-137. The former has a half-life of 8 days, making it very dangerous in the near term. If you think you are going to be exposed to radioactive iodine, you take potassium iodide, because your cells — being mostly chemists — cannot distinguish radioactive iodine from non-radioactive iodine. So you saturate your cells with one to block the absorption of the other.
Cesium-137 has a half-life of 30 years. This is the sort of stuff that seeps into the groundwater and increases the rate of cancer in your community by a fraction of a percent for a few decades.
10 micro-Sieverts = 1 milli-rem. Radiation poisoning is measured in Sieverts (as opposed to milli- or micro-Sieverts). Average background radiation on this planet exposes you to 2400 micro-Sieverts (= 240 milli-rem) per year. A chest x-ray exposes you to 80-100 micro-Sieverts (= 8-10 milli-rem). So if you read that radiation was measured at “1000 micro-Sieverts per hour”, you can think of that as “1000 hours’ exposure before symptoms appear” or as “10-12 x-rays per hour” or as “4000 times normal background radiation”. Which you pick will depend on which story you are trying to sell.
When purified water is exposed to radiation, it does not become dangerous; at least, not for long. So normal venting of steam from a nuclear reactor is no threat to anybody.
On the other hand, when sea water is exposed to radiation… Well, I suppose it depends what is in the sea water.
Here are some examples of good questions:
“Which isotopes are being released? Where? In what quantities?”
“Why are they pumping sea water instead of pure water into the reactors? Is that sea water turning into steam and being released?”
“How many micro-Sieverts per hour were measured, at what places, and for how long?”
“Are the containment vessels still intact? How do we know?”
Here are some examples of stupid questions:
“What is the worst-case scenario?”
“Could something like this happen in the U.S.?”
The only things I have read that I like:
One more thing. The question is not whether to build nuclear power plants. The question is what kind of power plants to build. If you can visualize and accept a monthly electricity bill 20 times higher than you pay today, then and only then are you allowed to answer “solar and wind”.
The realistic choices are fossil fuels and nuclear power, period. Whatever the result of this nuclear disaster, would the people of Japan have been better off with coal plants pumping CO2 and toxins into the air for the past 30 years? I do not know the answer. But I do know it is the right question, and I am pretty sure nobody is going to ask it.
Update 2011-03-15 01:40 EDT
On the other hand, when they start talking in hundreds of milli-Sieverts per hour… I wonder what the mechanism for that is (was?), and how long it will last.
The point is that all of these reports are meaningless without numbers. And not numbers like “1000 times normal background radiation”, which sounds bad but is actually trivial.
Stories about radiation measurements should always include when, where, how much, and for how long. Is that so much to ask?