You can let it evaporate way back somewhere on your property, but that takes some time. Ive done it, but have a empty lot next to my house. I did it because when I called the landfill/recycyle place here, they said call the fire dept., Fire dept. says call the land fill or try auto zone, but that is just for oil. I just kept getting the run around over and over...and over... haha
Now I take it to a large RV/marine repair facility that a friend works at. They have a guy that picks it up in a big tanker truck and recycles it some how and pays them for it. So they dont mind...lol They run it all through big spin cycles to separate oil/fuel/anti-freeze, etc..