Everybody should know that all places that sell motor oil are required (by law) to accept & recycle used motor oil. Take all your waste oil back to any auto parts store & dump it into their receptacle for used oil. No big deal. I soak all my stuff in diesel fuel. I use primary & secondary containment. I pour used diesel into a container & allow contaminants to settle on the bottom. Then, I decant the clean diesel into another container. After a while, I accumulate a few pints of sludge. I take it down to my auto parts store & dump it into their tank. No worries. Be good. Have fun.