Re: So basically....
Sure. Put these little suckers in isolated corners of the world. What could possibly go wrong?
Supposedly, there are designs which stop the terraists getting their hands on naughty stuff. Such as this one. Using molten sodium as a coolant seems like a bad idea for devices you intend to put everywhere, but other than that it is supposed to be safe.
Of course, it could be a bit of a problem if we put those everywhere and then somebody figures out how to hack them to get them to churn out weapons-grade material. Or even just pull out the depleted uranium and disperse it as an ultra-fine powder with highly toxic, carcinogenic, teratogenic and mutagenic properties.
With a half-life of 4.5 billion years, U-238 needs to be disposed of in a way that it can never get into the environment. With such a long half-life the radioactivity isn't the biggest the problem, it's the toxicity, etc. Heavy-metal poisoning with a very heavy metal.
Alternatively, make bullets and artillery shells out of U-238. They're pyrophoric, so burn (fiercely) upon impact (and sometimes ignite on leaving the barrel) turning into ultra-fine particles of uranium oxide that rapidly disperse into the environment and contaminate it (and will continue to do so long after the sun swells into a red giant and engulfs the earth). Nobody would be stupid enough to do that, would they? Not even because its mass and hardness make it an ideal material for penetrating tanks (it's even self-sharpening, so it doesn't mushroom out as other compositions do). Not even because the pyrophoric properties mean that once it has penetrated a tank it incinerates the occupants, turning them into what is often called "crispy critters." And although it makes a good area-denial weapon targeting enemy forces and civilians alike (which makes it illegal) the particles are so fine they disperse in the atmosphere and end up contaminating the whole planet. It would be incredibly stupid to do that, which is why it's exactly what the US (and allies) have been doing in warfare for decades. Thousands of tonnes of the stuff by now.
As you said, what can possibly go wrong?
Biting the hand that feeds IT
