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Solid Waste | Used Oil

Solid Waste Section

Used Oil

Revised On: Dec. 28, 2023 - 5:00 p.m.

What is Used Oil?

Used oil1 is any oil that has been refined from crude oil or any synthetic oil that is no longer suitable for its originally intended purpose due to physical or chemical impurities caused by use, handling, transportation or storage. Used oil includes motor oils, metalworking fluids, emulsions, transmission fluids, brake fluids, heating media, refrigeration oils, electrical oils and hydraulic fluids. Used oil does not include antifreeze, cleaning agents, and animal and vegetable oils. Gasoline, jet and diesel fuels are also not considered used oils but may be regulated as such if mixed with used oil. 

Used oil is recyclable. If it is not recyclable, it is considered waste oil. The EPA considers burning of used oil for energy recovery to be a form of recycling (e.g., space heaters and asphalt hot plants burn used oil for energy recovery). In Arizona, most used oil is burned for energy recovery. 

In addition to the federal definitions2 of used oil, the following Arizona Administrative Code definitions also apply:

  • Used oil includes oil that became contaminated as a result of its handling, transportation or storage.
  • Off-specification used oil is used oil that exceeds any of the allowable levels.3
  • On-specification used oil is used oil that is not considered off-specification used oil.4

Learn more about used oil specifications | Learn More >

Who Manages Used Oil?

The following manage used oil:

  • Generators
  • Transporters/transfer facilities
  • Processors/re-refiners, marketers and burners

Learn more about who manages used oil | Learn More >

Prohibited Practices

Used oil cannot be:5

  • Discharged into sewers or waters of the state without a permit issued by an appropriate regulatory authority
  • Incinerated, except at a facility authorized to incinerate hazardous wastes (burning for energy recovery is not considered incineration)
  • Used as a dust suppressant or contact herbicide
  • Disposed on land, except in a landfill that has an approved solid waste facility plan6
  • Stored in a surface impoundment

Learn more about how used oil is regulated in Arizona, including information about used oil collection centers, marketer's certification and reporting requirements | Learn More >

1 As defined in A.R.S. § 49-801(3)
2 40 C.F.R. § 279
3 40 C.F.R. § 279.11 and A.R.S. § 49-801(1)
4 A.R.S. § 49-801(2)
5 Per A.R.S. § 49-803
6 Meets the criterion established in 40 C.F.R., Parts 257 or 258