Used Motor Oil & Filters Illegal in Garbage & Drains Hazardous Waste Contact EHS and work with your Generator Assistant. Don't Dump in Trash or Down Drain Used motor oil is a major contaminant of waterways, so never dump down the drain or in the trash. Filters also leak toxic materials into waterways, which are slow to break down in the environment. Never Mix with Other Chemicals Service stations will not accept motor oil that has been contaminated with other products like antifreeze. Don’t mix your motor oil with anything else. Did You Know? What Happens to Recycled Motor Oil Used motor oil can be cleaned and recycled, which helps keep it out of waterways. Recycled oil is then used to make heating oil, asphalt and other petroleum-based products; it is usually not recycled and resold as motor oil.