It also should be noted that a coal-fired power plant releases more radiation every day than a nuclear plant does in its entire lifetime. Troof. Nuclear plants that aren't Chernobyl or Fukushima, that is. As far as other meltdowns go, Three Mile Island released less than a typical Tuesday at a coal plant, and Windscale was fully contained.
The Canadian pebble-bed CANDU design is really interesting, can't melt down, can't explode, and may lend itself to thorium fuel that doesn't leave that nasty waste anyway. The Canucks surprisingly own some rich thorium deposits and may just end up being the next Saudi Arabia as far as energy suppliers go. We shall see, eh?
Boring shit follows, feel free to skip if not interested in this stuff:
Re: coal plants. There's a goodly amount of polonium-210 in coal smoke. That's an alpha emitter, and dust particles with a molecule or three in them are thereby positively charged. Got an old CRT-style television set or monitor? The electron gun bit in the picture tube (i.e. the particle accelerator) puts a net negative charge on the glass, and polonium is precisely why dust sticks to the screen. It's radioactive as shit, any decent Geiger counter can measure it. Turn the tv off and you can plot the polonium's half-life pretty easily with a few measurements over an hour or so.
Re: CANDU, Chernobyl, and void coefficients: CANDU and the fast-breeder Soviet RBMK design used at good ol' Chernobyl #4 (and in something like seventy other reactors sprinkled aroud the former Soviet and Soviet-puppet zones) moderate them neutrons with graphite *and* the (high-pressure water) coolant. Problem is, if you let the thing get too hot, steam bubbles form and moderation doesn't go so well anymore. The neutron flux goes up and so does your reaction. This creates sort of a vicious-cycle thing as you get more steam bubbles, you make more steam bubbles, and things go faster and faster until it all gives up and the steam blows the 2-million pound steel lid off the top of your reactor. That's a bit of an oversimplification -- the control rods were a bad design, and xenon was forming in the core, plus a bunch of other stuff, but that's the basic idea. CANDU has a negative void coefficient also but is designed so it can't do anything of the sort. All Western reactors have positive void coefficients, so if steam bubbles form the reaction slows down and stops.
Re: Homemade bombs: If you have about 135 lbs. of uranium enriched to above 70% U-235 and a machine shop that doesn't object to making it into a hollow cylinder and a plug to fit in the middle of same, you can just drop the cylinder nine feet and it'll be moving fast enough to go supercritical. Little Boy, in your basement. I would not be near the basement at the time.
Re: Homemade bombs Part 2: at one time, not so long ago, there were a few hundred ex-Soviet nuclear subs rusting away in drydock, unguarded. Naval reactor fuel is better than bomb-grade.
Re: My Dinner with Robert Oppenheimer: I don't remember it, because I was around two years old, but he came by the house once for a Mom-cooked dinner. I didn't find out about this until somewhat later, like 40 years later. (I'd hafta check the dates - I'm currently 35 or thereabouts (I think) so the math doesn't work quite right, but it was something like that.)
