Pollution Prevention Guides for
Auto Body Shops - Fact Sheet 3

Defining A Waste

A material is considered a waste by state and federal regulations when it can no longer be used or reused and requires treatment or disposal. Before a waste can be treated or disposed of, you have to determine if the waste is non-hazardous or hazardous. This can be done by either applying your knowledge of what is in the waste or analyzing the waste by an approved test method. There are specific management and disposal rules and regulations that must be followed if the waste is determined to be hazardous or non-hazardous.

Defining A Hazardous Waste

Knowing what makes a waste hazardous is important for understanding why it should be reduced or eliminated, and for selecting less-hazardous alternatives.

There are two types of regulated hazardous waste defined by the United States Environmental Protection Agency (EPA): characteristic and listed.


A waste may be considered hazardous if it exhibits any one of the following characteristics (Figure 2): ignitable, corrosive, reactive, and toxic.


Ignitable - An ignitable characteristic waste is a liquid with a flash point (see Glossary for definition) below 140oF; a non-liquid capable of causing fire through friction, absorption of moisture, or spontaneous chemical changes; and/or a flammable compressed gas. Examples include solvents and mineral spirits.

Corrosive - A corrosive characteristic waste is an aqueous-based liquid with a pH less than or equal to 2.0 (strong acid) or a pH greater than or equal to 12.5 (strong base). Examples include battery acid and alkaline cleaning solvents.

Reactive - Reactive characteristic wastes are unstable or undergo violent chemical reactions when combined with water or other materials. Examples include hydrogen sulfide and bleaches.

Toxic - A toxic characteristic waste is hazardous due to the presence of metals or organic compounds. A test, called the Toxicity Characteristic Leaching Procedure (TCLP), simulates leaching of the contaminant through a landfill environment and into groundwater. There are 40 constituents that EPA has established concentration limits for in the TCLP test. Examples include wastes with high metal (lead, silver, etc.) content, such as hot tank wastes.


A waste can also be considered hazardous if it appears on any one of four lists of hazardous wastes contained in the federal Resource Conservation and Recovery Act (RCRA) regulations. These wastes contain toxic constituents that have been found to be harmful to human health and the environment. More than 400 chemicals can be found on these lists.

F-Listed Wastes - F-listed wastes are derived from a wide variety of sources. Examples of F-listed wastes include specific halogenated solvents used in degreasing (tetrachloroethylene and methylene chloride) and non-halogenated solvents (xylene and acetone).

K-Listed Wastes - K-listed wastes are derived from specific manufacturing processes. Examples of K-listed wastes include wastewater treatment sludge from the production of certain inorganic pigments.

P-Listed (Acute*) and U-Listed Wastes - P- and U-listed wastes are toxic discarded chemical products or off-specification products and residues. Examples of P- and U-listed wastes include 2,4-Dinitrophenol (2,4-D) and formaldehyde (The Small Business Handbook For Managing Hazardous Wastes, 1996).

*Acute (P-Listed) wastes are determined by EPA to be so dangerous in small amounts that they are regulated more stringently.

Exempt Hazardous Wastes

There are wastes that meet the definition of a hazardous waste but may be exempt from hazardous waste regulations. Instead, they are regulated under other state or federal regulations (to be discussed later in this guide). They include:

  • Hazardous wastes generated in the home (for example oven cleaners and drain cleaners)
  • Spent lead-acid batteries to be sent off-site for reclamation (for example vehicle batteries)
  • Scrap metal to be recycled
  • Asbestos to be disposed of
  • Polychlorinated biphenyls (PCBs) to be disposed of - Regulated as a toxic substance by the EPA under the Toxic Substance Control Act.
  • Chlorofluorocarbons (CFCs) to be disposed of - Regulated as a volatile organic compound by EPA under the Clean Air Act.

Universal Wastes

Based on United States Environmental Protection Agency standards (EPA), Universal Waste Regulations encourage the recycling of specific hazardous wastes. These wastes, if destined for recycling and not for disposal, are called universal wastes (UW)*.

Universal wastes include:

  • Spent batteries other than lead-acid batteries
  • Spent or canceled pesticides that have been recalled or managed by a waste pesticide collection program
  • Mercury-containing thermostats
  • Spent electric tubes or bulbs that are hazardous due to heavy metals concentrations

*Note that household hazardous wastes are excluded from universal waste regulations

The following is a brief description of universal waste management:

  • Universal waste generator is any person, by site, whose act or process produces hazardous waste or whose act first causes a hazardous waste to become subject to regulation.
  • Universal Waste Handler is a generator of universal waste or the owner or operator of a facility that receives universal waste from other universal waste handlers, accumulates universal waste, and sends universal waste to another universal waste handler, to a destination facility, or to a foreign facility.
  • Small Quantity Handler of Universal Waste means a universal waste handler who does accumulate less than a total of 5,000 kilograms (kgs) of universal waste at any time.
  • Large Quantity Handler of Universal Waste is a universal waste handler who accumulates a total of 5,000 kgs or more of universal waste at any time. This designation is retained through the end of the calendar year in which the total of 5,000 kgs or more of universal waste is accumulated.
  • Universal Waste Transporter transports universal waste by air, rail, highway, or water.
  • Universal Destination Facility treats, recycles, or disposes of universal waste.
In general, universal waste generators:
  • May not dispose of universal waste (by definition it must be recycled).
  • May not intentionally dilute or treat universal waste.
  • Must manage universal waste so as to prevent releases to air, water, or soil.
  • Must immediately contain any releases of universal waste and clean up the releases accordingly.
  • Must inform employees regarding proper handling of universal waste and emergency response procedures.
  • May transport universal waste only to other universal waste handlers, destination facilities, or a foreign destination

Determining Your Generator Size

If your shop creates regulated hazardous waste, you are considered a hazardous waste generator. There are three types of hazardous waste generators defined in federal and state hazardous waste regulations: conditionally exempt, small, and large. Your generator status depends on the amount of hazardous waste your shop produces each calendar month.

Conditionally Exempt Generator

Conditionally exempt generators (CEGs) generate no more than 220 lbs (100 kgs) or about 25 gallons of hazardous waste, or no more than 2.2 lbs (1 kg) of acute hazardous waste in any calendar month. CEGs are required to meet much lighter regulatory requirements than SGs and LGs.

Small Generator

Small generators (SGs) generate between 220 and 2,200 lbs (100 and 1,000 kgs) of hazardous waste in any calendar month.

Large Generator

Large Generators (LGs) generate 2,200 lbs (1,000 kgs) or more of hazardous waste, or more than 2.2 lbs (1 kg) of acute hazardous waste in any calendar month (The Small Business Handbook For Managing Hazardous Wastes, 1996).

Hazardous Waste Management

How you store, recycle, treat, and dispose of your hazardous waste depends primarily on your generator size (discussed previously). The following is a brief description of the management requirements for hazardous waste generators.

Conditionally Exempt Generators (CEGs)

CEGs are required to:

  • Identify all hazardous wastes generated.
  • Limit the amount of hazardous waste generated in any month to less than 220 lbs (100 kgs).
  • CEGs do not have waste container labeling or accumulation time limit requirements unless they accumulate more than 2,200 pounds of hazardous waste. If they accumulate more than 2,200 pounds, all CEGs' hazardous waste must be regulated as if generated and accumulated by a Small or Large Generator (described below).
  • Never generate more than 2.2 lbs (1 kg) of acute hazardous waste or 220 lbs (100 kgs) of soil contaminated from acute hazardous waste spills in any calendar month.

Dispose of hazardous waste at one of the following facilities:

  • A legitimate recycling facility
  • A permitted Treatment, Storage, and Disposal (TSD) Facility
  • A licensed Class II (municipal) solid waste management facility in accordance with state solid waste management regulations, only if the waste is a solid waste, and accepted by the facility owner/operator

Small Generators (SGs)

SGs are required to:

  • Identify all hazardous waste generated.
  • Obtain a U.S. Environmental Protection Agency (EPA) Identification Number (defined in Glossary section).
  • Mark containers of hazardous waste in accumulation areas (defined in Glossary section) clearly with the words Hazardous Waste and an accumulation start date. SGs may store their hazardous waste on-site for up to 180 days (or up to 270 days if the waste must be transported further than 200 miles to a designated facility) without a permit from the DEQ. Satellite accumulation containers must be marked with the words Hazardous Waste, or with other words that identify the containers' contents.
  • Maintain a log book listing the type and amount of hazardous waste generated per month, what has been removed, etc.
  • Have emergency response measures in place.
  • Store and label hazardous waste appropriately.
  • Manifest all hazardous waste sent off-site.
  • Dispose of hazardous waste only at a permitted TSD Facility.
Large Generators (LGs)

LGs are required to follow all the above requirements for SGs, in addition to more stringent hazardous waste management requirements not covered in this guide. For example, LGs can store their hazardous waste on-site for up to 90 days without a permit. Satellite accumulation containers must be marked with the words Hazardous Waste, or with other words that identify the contents of the containers.

Defining A Solid Waste

A non-liquid waste that fails to meet the definition of a regulated hazardous waste may be considered a solid waste. Solid waste can be defined as all putrescible and non-putrescible wastes, including garbage, rubbish, ash, sludge from sewage treatment plants, dead animals, appliances, construction and demolition debris, and wood waste.

There are two major types of solid waste landfills:

  • Class II landfills - Designed to accept municipal solid waste and non-hazardous industrial wastes.
  • Class III landfills - Designed to accept inert materials such as rock, soil, untreated wood waste, and tires.
Container sites, transfer stations, and composting facilities are also considered solid waste management facilities.

Montana State University Extension Service
Pollution Prevention Program Taylor Hall Bozeman, Montana 59717
(406) 994-3451
funded by
The United States Environmental Protection Agency
(Fact Sheet 3 of 18)

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