Used motor oil being poured into an empty oil container for disposal

Oil is used in a wide range of applications, such as engine lubrication oil, cutting oil, hydraulic fluids, gear oil and insulation in dielectric transformers. Used oil is any oil that has been refined from crude oil, or any synthetic oil, that has been used and, as a result of such use, is contaminated by physical or chemical impurities. During normal use, impurities such as dirt, metal scrapings, water or chemicals can mix with the oil. Eventually, the used oil must be replaced with clean oil. All used oil, whether in small or large quantities, produced by farmers, households, do-it-yourself mechanics, small industry or large industry, must be collected and properly recycled.

Why is Used Oil Harmful?

Used oil is classified as a hazardous waste and must be handled responsibly. Used oil contains metals such as tin, copper and lead. According to the American Petroleum Institute, 200 million gallons of used oil are improperly disposed each year. When used oil is poured down the drain, it contaminates our drinking water and groundwater. The metals and chemicals that mix with the oil during use can be harmful to humans and the environment. Oil is slow to degrade and sticks to everything. It can kill fish and other organisms in our lakes and streams. According to the U.S. Environmental Protection Agency, used oil from just one oil change can contaminate one million gallons of fresh water.

How is Used Oil Recycled?

Used oil can be re-refined and used as a lubricant for other equipment. It takes 42 gallons of crude oil, but only 1 gallon of used oil, to produce 2.5 quarts of high-quality lubricating oil. Used oil can also be used as raw materials in other processes or reprocessed into fuel oils. Two gallons of used oil can power an average household for almost a day. 

Used oil is treated or recycled in a certified facility to remove the harmful contaminants. These processes can include thermal refining for improved fuel quality, mechanical separation (filtration and centrifuging) and chemical separation to remove the contaminants. 

Where Can I Take My Used Oil?

If you are one of the many people who change their own oil, you need to know how to properly collect and dispose your used oil. Make sure to use a drip pan to catch the oil and and take care not to spill any on the ground. Pour the used oil into a clean leak-proof can or plastic container with a tight-fitting lid. Do not mix the oil with anything else. For other tips on how to change your oil, visit Minnesota Pollution Control Agency's Changing Your Oil

Waste oil, including lubricating oil, transmission oil, transformer oil, hydraulic oil and fuel oil, is not allowed to be disposed in Missouri landfills. This landfill ban was done in order to conserve landfill space, promote recycling and reduce the chance of environmental contamination. Below are several options available to drop off your used oil for recycling:

  • Contact your local vehicle service centers or auto parts stores and ask if they will accept your used oil
  • Contact your local waste collectors and ask if they have a designated drop-off center for used oil
  • Participate in a collection event hosted by your city, county or solid waste management district
  • Search the Missouri Materials Management Directory to find local drop-off locations for used oil

Used oil filters may be disposed with household trash, as long as they have been well drained. However, the department recommends recycling the oil filter with your used oil. Used oil filters contain reusable scrap metal, which steel producers can reuse as scrap feed.

Are You a Business?

If you are a business or non-profit, visit Hazardous Waste Compliance and Assistance and EPA's Managing Used Oil: Answers to Frequent Questions for Businesses. If you have any questions, or need additional assistance, please contact the department’s Waste Management Program.