Skid wrote: ↑Sat Jul 04, 2020 8:57 am
Well, when you concentrate all that uranium in one area the levels increase to hazardous levels. Perhaps you should go work in an uranium mine with no PPE if it is so safe?
I would actually wear signifcantly less PPE than at work doing welding.
Look. It isn't enough to throw some U-238 on a pile to make it dangerous. That's not how it works. U-238 is primarily a weak alpha emitter. That means it emits Alpha-radiation (duh.) some Beta radiation and trace amounts of Gamma-radiation. Gamma radiation itself is very dangerous, but not in the amounts emitted by U-238. Alpha radiation does not penetrate the outer layer of skin, or a thin sheet of paper, Beta radiation is stopped by a T-shirt and both types lose most of their energy after a foot or two of travel through air. In fact, handling uranium ore or even Yellowcake all day in a Tshirt and latex gloves will hurt 1000x less than welding in a T-shirt for 1 minute or standing in the sun for an hour.
To make Uranium dangerous, you have to enrich it with U235, the fissile isotope. Commercially used Uranium is enriched with about 3% U235, while you need over 30% for nuclear weapons grade Uranium, which then has to be condensed using explosives to reach critical mass. Depleting Uranium does exactly the opposite, it makes the stuff that's naturally occuring even less radioactive by lowering the amount of U235 even further.
If you put sheets of U238 on a pile, the outer layer would actually protect you from the radiation of the inner layers, because U238 is not fissile, the radiation not cumulative. In fact U238 is just used as a carrier for U235. When you pull the rod out of a used core, The U238 is still there but the U235 has decayed and left over its highly irradiating fission products.
Depleted U238 is not only used for Armor Piercing ammunition, but also Tank Armor.
The radio-toxicity of DU is insignificant. The toxicity of the metal is much more dangerous. But it's just as toxic as Lead. Lead is in fact the decay product of U238. Lead was Uranium-238 5 billion years ago. We don't eat lead anymore tho.
So TL;DR:
Depleted Uranium in yer yard = Just as harmless as the Uranium IN the ground.
Irradiated country = Impossible. Most of the Background radiation is coming from Radon gas. Even the fossile Uranium plays a small part in it. A couple of tons of mildly radioactive material that irradiates an area of 10m² surrounding it's surface has exactly 0 influence on that.
Half life of billions of years = That actually indicates how little radioactive the material is. The longer the half life, the lower the amount of energy emitted in a given timeframe.