The Dangers of Nuclear Waste

Most uranium that we take out of the ground is 238, whereas this also you 235. U-235 is very fissile while U-238 needs faster neutrons. There must be some waste there right? Some I think they call this depleted uranium. If the market price for uranium goes up we use more of that depleted uranium. So again this is not waste in the sense that these are byproducts we can never use again. It's that we do not use them now because it's economically cheaper to just not use it.