--- Horace > AFAIK "depleted uranium" typically means the stuff left over after U235 separation process from the mined natural uranium, not what's left over after burning U in fuel rods.
True, and there was implication otherwise. > Depleted uranium has about 1/3 the U235 that natural uranium does. More like 40% remains but in either case, the half-life of either 238 or 235 is in the billions of years, and fairly close (minimum difference) - but this is NOT what makes the depleted material more radioactive ... What makes it more radioactive is the radon "daughters" and other trace actinides which are left in the depleted material because they are neutron poisons. These can be (literally) millions of times more radioactive- so that even a trace amount makes a huge difference. The military has tried to downplay this fact because they insist that the depleted metal is a safe and affordable heavy metal for armor piercing rounds. It is not safe, by any stretch of the imagination, and is the root cause of many illnesses of troops for the fist Gulf war and Bosnia- who still excrete it in urine 20 years after exposure ... and if its 'true cost' were accounted for, it would not be affordable either. Jones
