Managing Used Oil

U.S. Environmental Protection Agency

Service stations, fleet maintenance facilities and quick-lube businesses that generate and handle used oil need to know the “good housekeeping” requirements for used oil handlers.

This article summarizes the U.S. Environmental Protection Agency’s (EPA’s) used oil management standards detailed in Title 40 of the Code of Federal Regulations (CFR) Part 279.

What is Used Oil?

The EPA’s regulatory definition of used oil is as follows: 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.

Simply put, used oil is exactly what its name implies - any petroleum-based or synthetic oil that has been used. During normal use, impurities such as dirt, metal scrapings, water or chemicals can get mixed in with the oil, such that in time, the oil no longer performs well.

This used oil must eventually be replaced with virgin or re-refined oil to do the job at hand. EPA’s used oil management standards include a three-pronged approach to determine if a substance meets the definition of used oil. To meet EPA’s definition of used oil, a substance must meet each of the following three criteria:

  • Origin - Used oil must have been refined from crude oil or made from synthetic materials. Animal and vegetable oils are excluded from EPA’s definition of used oil.

  • Use - Consider whether and how the oil is used. Oils used as lubricants, hydraulic fluids, heat transfer fluids, buoyants and for other similar purposes are considered used oil. Unused oil such as bottom clean-out waste from virgin fuel oil storage tanks and virgin fuel oil recovered from a spill do not meet EPA’s definition of used oil because these oils have never been used. EPA’s definition also excludes products used as cleaning agents or solely for their solvent properties, as well as certain petroleum-derived products like antifreeze and kerosene.

  • Contaminants - Take into account whether or not the oil is contaminated with either physical or chemical impurities. In other words, to meet EPA’s definition, used oil must become contaminated as a result of being used. This aspect of EPA’s definition includes residues and contaminants generated from handling, storing and processing used oil. Physical contaminants could include metal shavings, sawdust or dirt. Chemical contaminants could include solvents, halogens or saltwater.

How is Used Oil Recycled?

Once oil has been used, it can be collected, recycled and used over and over again. An estimated 380 million gallons of used oil are recycled each year. Recycled used oil can sometimes be used again for the same job or can take on a completely different task. For example, used motor oil can be re-refined and sold at the store as motor oil or processed for furnace fuel oil. Aluminum rolling oils also can be filtered on-site and used again.

Used oil can be recycled in the following ways:

  • Reconditioned on-site, which involves removing impurities from the used oil and using it again. While this form of recycling might not restore the oil to its original condition, it does prolong its life.

  • Inserted into a petroleum refinery, which involves introducing used oil as a feedstock into either the front-end of the process or the coker to produce gasoline and coke.

  • Re-refined, which involves treating used oil to remove impurities so that it can be used as a base stock for new lubricating oil. Re-refining prolongs the life of the oil resource indefinitely. This form of recycling is preferred because it closes the recycling loop by reusing the oil to make the same product that it was initially, and therefore uses less energy and less virgin oil.

  • Processed and burned for energy recovery, which involves removing water and particulates so that used oil can be burned as fuel to generate heat or to power industrial operations. This form of recycling is not as preferable as methods that reuse the material because it enables the oil to be reused only once. Nonetheless, valuable energy is provided (about the same as provided by normal heating oil).

Recycling used oil is good for the environment and the economy for a number of reasons:

  • Re-refining used oil takes only about one-third the energy of refining crude oil to lubricant quality.
  • It takes 42 gallons of crude oil, but only one gallon of used oil to produce 2.5 quarts of new, high-quality lubricating oil.
  • One gallon of used oil processed for fuel contains about 140,000 British thermal units (BTUs) of energy.
Used Oil Is:
Used Oil Is Not:
  • Synthetic oil - usually derived from coal, shale or polymer-based starting material
  • Engine oil - typically includes gasoline and diesel engine crankcase oils and piston-engine oils for automobiles, trucks, boats, airplanes, locomotives and heavy equipment
  • Transmission fluid
  • Refrigeration oil
  • Compressor oils
  • Metalworking fluids and oils
  • Laminating oils
  • Industrial hydraulic fluid
  • Copper and aluminum wire drawing solution
  • Electrical insulating oil
  • Industrial process oils
  • Oils used as buoyants

This list does not include all types of used oil.

  • Waste oil that is bottom clean-out waste from virgin fuel storage tanks, virgin fuel oil spill cleanups, or other oil wastes that have not actually been used
  • Products such as antifreeze and kerosene
  • Vegetable and animal oil, even when used as a lubricant
  • Petroleum distillates used as solvents

Oils that do not meet EPA’s definition of used oil can still pose a threat to the environment when disposed of and could be subject to the RCRA regulations for hazardous waste management.

Handling Used Oil

The following businesses handle used oil:

Generators are businesses that handle used oil through commercial or industrial operations or from the maintenance of vehicles and equipment. Generators are the largest segment of the used oil industry. Examples of common generators are car repair shops, service stations, quick-lube shops, government motor pools, grocery stores, metal working industries and boat marinas. Farmers who produce less than an average of 25 gallons of used oil per month are excluded from generator status. Individuals who generate used oil through the maintenance of their personal vehicles and equipment are not subject to regulation under the used oil management standards.

Collection centers and aggregation points are facilities that accept small amounts of used oil and store it until enough is collected to ship it elsewhere for recycling. Collection centers typically accept used oil from multiple sources that include both businesses and individuals. Aggregation points collect oil only from places run by the same owner or operator and from individuals.

Transporters are companies that pick up used oil from all sources and deliver it to re-refiners, processors or burners. Transfer facilities include any structure or area where used oil is held for longer than 24 hours, but not longer than 35 days. Examples of transfer facilities are loading docks and parking areas.

Re-refiners and processors are facilities that blend or remove impurities from used oil so that it can be burned for energy recovery or reused. Included in this category are re-refiners who process used oil so that it can be reused in a new product such as a lubricant and recycled again. EPA’s management standards focus primarily on this group of used oil handlers.

Burners burn used oil for energy recovery in boilers, industrial furnaces or in hazardous waste incinerators.

Marketers are handlers who either direct shipments of used oil to be burned as fuel in regulated devices, or claim that certain EPA specifications are met for used oil to be burned for energy recovery in devices that are not regulated. They also sometimes help move shipments of used oil to burners. By definition, marketers must also fall into at least one of the above categories.

Standards to Follow

If your business generates or handles used oil, there are certain good housekeeping practices to be followed. These required practices, called management standards, were developed by EPA for businesses that handle used oil. The management standards are common sense, good business practices designed to ensure the safe handling of used oil, to maximize recycling and to minimize disposal.

The standards apply to all used oil handlers, regardless of the amount of the oil they handle. Although different used oil handlers may have specific requirements, the following requirements are common to all types of handlers. These requirements relate to storage and to cleaning up leaks and spills, as follows:

  • Label all containers and tanks as used oil.

  • Keep containers and tanks in good condition. Don’t allow tanks to rust, leak or deteriorate. Repair structural defects immediately.

  • Never store used oil in anything other than tanks and storage containers. Used oil may also be stored in units that are permitted to store regulated hazardous waste. Tanks and containers storing used oil do not need to be RCRA2-permitted, however, as long as they are labeled and in good condition. Storage of used oil in lagoons, pits or surface impoundments that are not permitted under RCRA is prohibited.

Oil Leaks and Spills

  • Take steps to prevent leaks and spills. Keep machinery, equipment containers and tanks in good working condition and be careful when transferring used oil. Have sorbent materials available on-site.

  • If a spill or leak occurs, stop the oil from flowing at the source. If a leak from a container or tank cannot be stopped, put the oil in another holding container or tank.

  • Contain spilled oil. Containment can be accomplished by erecting sorbent berms or by spreading a sorbent over the oil and surrounding area.

  • Clean up the oil and recycle the used oil as you would have before it was spilled. If recycling is not possible, first ensure that the used oil is not a hazardous waste and dispose of it appropriately. All used cleanup materials, from rags to sorbent booms, that contain free-flowing used oil also must be handled according to the used oil management standards. Remember, all leaked and spilled oil collected during cleanup must be handled as used oil. If you are a used oil handler, you should become familiar with these cleanup methods. They may also be part of a spill response action plan.

  • Remove, repair or replace the defective tank or container immediately.

Record Keeping
EPA uses 12-digit identification (ID) numbers to track used oil. Transporters hauling used oil must have a valid EPA ID number, and generators, collection centers and aggregation points must use transporters with EPA ID numbers for shipping used oil off-site. If an ID number is needed, the EPA regional office or state director should be contacted.

Generators, collection centers, aggregation points and any handler that transports used oil in shipments of less than 55 gallons do not need an ID number, but may need a state or local permit.

Used oil transporters, processors, burners and marketers also must record each acceptance and delivery of used oil shipments. Records can take the form of a log, invoice or other shipping document and must be maintained for three years.

Re-refiners, processors, transfer facilities and burners must have secondary containment systems (for example, oil-impervious dike, berm, or retaining wall and a floor) so that oil cannot reach the environment in the event of a leak or spill. EPA also encourages generators to use a secondary containment system to prevent used oil from contaminating the environment.

Burners of used oil that meet a certain set of quality standards called the used oil specifications are not regulated under the used oil management standards, as long as the used oil is burned in appropriate boilers, furnaces or incinerators.

It is important to know and understand your state regulations governing the management of used oil, because they may be stricter than those of the EPA. Your state or local environmental agency should be contacted to determine the best course of action.

Mixing Used Oil and Hazardous Waste
In addition to EPA’s used oil management standards, your business may be required to comply with federal and state hazardous waste regulations if your used oil becomes contaminated from mixing it with hazardous waste.

If used oil is mixed with hazardous waste, it probably will have to be managed as a hazardous waste. Hazardous waste disposal is a lengthy, costly and strict regulatory process. The only way to ensure that used oil does not become contaminated with hazardous waste is to store it separately from all solvents and chemicals and not mix it with anything.

If you believe your used oil might be mixed with a hazardous waste, call the RCRA Hotline. Hotline representatives can answer most of your questions or direct you to appropriate state environmental offices.

Managing Used Oil Filters

The Filter Manufacturers’ Council3 maintains a database to encourage the proper management of used oil filters. The database contains the proper management requirements for each state, as well as the following:

  • Overviews of federal and state regulations relevant to the management of oil filters.
  • Addresses and phone numbers of the regulatory agencies governing the management of used filters in each state.
  • A listing of companies, by state, that transport, process and recycle used filters.

Avoid Costly Cleanups

Meeting the following conditions relieves service station dealers from responsibility for costly cleanups and liabilities associated with off-site handling of used oil. To meet these conditions, service stations must:

  1. comply with the management standards discussed

  2. not mix used oil with any hazardous substance, and

  3. accept used oil from do-it-yourselfers (DIYs) and send it for recycling. The RCRA Hotline provides complete details regarding this liability exemption.

Recommended Cleanup Practices
EPA recommends, but does not require, the following cleanup practices for used oil handlers:

  1. maximize the recovery of used oil

  2. minimize the generation of used oil sorbent waste by choosing reusable sorbent materials

  3. use the spent sorbent materials to produce recycled sorbent materials, and

  4. buy sorbent materials with recycled content.

Extraction devices (such as centrifuges, wringers and compactors) can be used to recover used oil from reusable sorbent materials. Sorbent pads can be reused between two and eight times depending on the viscosity of the used oil. These technologies, while not required, can be used to reduce the number of sorbent pads ultimately sent for remanufacture, energy recovery or disposal.

The potential to reduce waste and save money (that is, lower disposal costs for spent pads and lower per use cost of sorbent pads) by reusing and recycling sorbent pads can be substantial.

Managing Cleanup Materials
As much of the free-flowing oil as possible on rags or other sorbent materials used to clean up a leak or spill should be removed, and the oil should be managed as the used oil would have been manged before it spilled.

Once the free-flowing used oil has been removed from these materials, they are not considered used oil and may be managed as solid waste as long as they do not exhibit a hazardous waste characteristic. Note, however, that materials from which used oil has been removed continue to be regulated as used oil if they are to be burned for energy recovery (regardless of the degree of removal).

Conserving Oil

  • Minimize the amount of used oil you produce. The less used oil that is produced in the first place, the less that ultimately has to be handled. Businesses can filter, separate and recondition used oil to prolong its usable life.

  • Purchase re-refined used oil products instead of virgin oil products. Re-refined oil works just as well as virgin oil. Products that display the American Petroleum Institute (API) “starburst” meet the same high-quality specifications as virgin oil.

  • Practice safe management of used oil. Don’t mix used oil with anything. Always store used oil in leak-proof containers that are in secure areas safely away from workers and the environment. Send used oil to a re-refiner whenever possible.


Subscribe to Machinery Lubrication