I have often wondered what they do with the used oil? We have a county recycling center where we take our trash and recycle stuff (plastic, newspaper, etc.) They have a tank that we dump drain oil in. I gotta believe that I am not the only one that dumps everything in there; motor oil, ATF, brake fluid, gear oil etc. What can they possibly do with that stuff then?
I do know the local process for separating the solids is highly efficient. They use slave labor (ie rent prisoners from the state).