• The statutory definition of a solid waste is completely irrespective of the physical form of the waste. A "solid" waste can be just as easily liquid or gas. A material is considered a solid waste if it:
  • Is a solid, semi-solid, liquid, or contained gaseous material which is discarded or has served its intended purpose?
  • Is abandoned?
  • Is being recycled by being placed on the ground (and that is not the normal use), burned for energy recovery, reclaimed, or accumulated more than one year.
  • Is inherently waste-like (e.g., dioxin wastes)?
  
  
• If the material in question meets any of the provisions above, you may have a solid waste. If you answered NO to all of the above provisions, you do not have a solid waste.

YES - click here to go to Step #2 below.
NO - the material does not qualify as a solid waste, and therefore cannot be regulated under RCRA Subtitle C.

• EPA grants specific exclusions from some hazardous waste regulations if certain conditions are met. Some materials are excluded from the definition of solid waste, while some solid wastes are excluded from the definition of hazardous waste. Knowing these exclusions can be helpful in waste management programs.

• Some materials that are excluded from the definition of solid waste (and therefore are NOT hazardous) include:
  • Domestic sewage
  • Industrial wastewater discharges
  • Radioactive waste
  • Spent wood preserving solutions that are reclaimed and reused in the wood preserving process
  • Processed scrap metal
  • Irrigation return flow
  • In situ mining waste
  • Secondary materials that are reclaimed and returned to the original process, if the reclamation and return process is totally enclosed.

  These wastes are not hazardous because they are not considered solid waste.

• Some solid wastes are excluded from the definition of hazardous wastes:
  • Household waste (pesticides, cleaners)
  • Some agricultural wastes that are returned to the soils as fertilizers
  • Fossil fuel combustion wastes
  • Cement kiln dust (unless the facility burns hazardous waste as fuel)
  • Arsenically treated wood wastes generated from a person using wood for its intended purpose
  • Petroleum-contaminated media that is subject to the UST corrective action program
  • Used oil filters that have been hot drained
  • Used chlorofluorocarbon refrigerants that are being reclaimed for further use.

  These solid wastes are excluded from the definition of hazardous waste by EPA.

• In addition, some recycled materials are not classified as solid waste. Materials are not solid wastes IF:
  • They are being used as substitutes for commercial products
  • Returned back to the original process without first being reclaimed or land disposed.

  This exemption is not valid if the materials are burned for energy recovery or used to make a product that will be applied to the land.

• Samples collected for lab analysis are exempt from RCRA regulation until it is determined that they are to be disposed of.

• Used oil that exhibits hazardous characteristics can be excluded if recycled. It is regulated under Standards for the Management of Used Oil (40 CFR Part 279).

• Universal wastes (including batteries, pesticides, mercury-containing thermostats, switches, and thermometers, and electric lamps) may also qualify for reduced regulation.

• The list above is NOT comprehensive. If your waste is not on the list above, it may still be excluded from RCRA regulation. See 40 CFR 261.4 for a complete list of those wastes exempt from hazardous waste regulation. Furthermore, if your waste IS listed above, that does not mean you are automatically exempt. Each exemption above is conditional and facility managers should review applicable sections of 40 CFR 261 and contact their State's hazardous waste program for clarification on exemptions.

YES - the waste is exempt (not regulated) under RCRA Subtitle C.
NO - click here to go to Step #3 below.

• EPA "lists" hazardous wastes that fall into four categories;

  • F-listed wastes: The F list includes wastes from common industrial processes. Because they are not specific to one type of industry, they are called wastes from non-specific sources. This list includes for example many types of spent (or used) solvents. See 40 CFR 261.31 to see if your waste is F-listed.
  • K-listed wastes: The K list includes wastes from specific industrial processes, such as wood preservation, organic chemical production, and pesticide manufacturing. See 40 CFR 261.32 for the complete list of manufacturing process wastes to see if your facility might have a K-listed waste.
  • P- and U-listed wastes: These two lists designate certain commercial chemical products as hazardous when disposed of unused. These unused chemicals may become wastes in a number of ways. Some can be spilled while in use while others can be intentionally discarded if out of specification. For a waste to qualify as a P- or U-listed waste, it must meet all three of the following criteria:
    • The formulation must contain at least one chemical on the P or U list
    • The chemical in the waste must be unused
    • The chemical in the waste must be in the form of a CCP.
      *A CCP is a chemical that is of technical (commercial) grade, 100% pure, and the only active ingredient in the formulation.

  There are hundreds of P- and U-listed wastes. Facility managers should look in 40 CFR 261.33 to see if chemicals present on-site are hazardous if disposed of unused. Please note that the chemicals with the "P" code are acutely hazardous. Generators with acutely hazardous waste are subject to different accumulation limits for those wastes.

YES - the waste is a listed waste and is therefore regulated under RCRA Subtitle C.
NO - click here to go to Step #4 below.

• Solid wastes that are not directly listed in 40 CFR Part 261 may still be hazardous. EPA uses a classification system based on the four properties of solid wastes. If a material exhibits at least one of these characteristics, it is classified as a hazardous waste. The four properties are:
  • IGNITABILITY
    A substance is ignitable if it displays any of the following properties.
    • A liquid with a flashpoint of less than 60° C (140° F);
    • A non-liquid that is capable, under standard temperature and pressure, of causing fire through friction, absorbtion of moisture, or spontaneous chemical changes, and when ignited, burns so vigorously and persistently that it creates a hazard;
    • An ignitable compressed gas;
    • An oxidizer (such as a chlorate or peroxide).
    Details on the ignitability characteristic are included in 40 CFR 261.21.

  • CORROSIVITY
    A substance is corrosive if it displays any of the following properties:
    • An aqueous material with a pH less than or equal to 2 or greater than or equal to 12.5;
    • A liquid that corrodes steel at a rate of at least 0.25 inches per year at 55° C (130° F); NOTE: A waste that is not aqueous and contains no liquid falls outside the definition of EPA corrosivity.
    Details on the corrosivity characteristic are included in 40 CFR 261.22.

  • REACTIVITY
    A substance is reactive if it displays any of the following properties.
    • Normally unstable and readily undergoes violent change without detonating;
    • Reacts violently with water;
    • Forms potentially explosive mixtures with water;
    • A cyanide or sulfide bearing waste which can generate fumes in a quantity sufficient to present a danger to human health.
    • Capable of detonation
    • A forbidden explosive, or a Class A or Class B explosive, as defined in Department of Transportation regulations in 49 CFR Part 173.
    Details on the reactivity characteristic are included in 40 CFR 261.23.

  • TOXICITY
    A substance is toxic if it exceeds the concentrations for contaminants listed in the "Maximum Concentration of Contaminants for the Toxicity Characteristic" table, presented in 40 CFR 261.24. A specific test, the Toxicity Characteristic Leaching Procedure (TCLP) must be conducted to determine if the waste is classified as toxic. Details on the toxicity characteristic are included in 40 CFR 261.24.

• EPA designates specific, standardized test methods that are to be used when determining the characteristics of a waste. These techniques are listed in the above mentioned sections.

Is the solid waste a characteristic hazardous waste?

YES - the waste is a characteristic waste and is therefore regulated under RCRA Subtitle C.
NO - click here to go to Step #5 below.

• The "Mixture Rule" states that mixtures of solid waste and listed hazardous waste must be regulated as hazardous waste. There are two ways to determine if a material is regulated under the mixture rule:
  • If the material is a mixture of a solid waste and a hazardous waste, and the mixture exhibits one or more of the characteristics of hazardous waste;
  • If the material is a mixture of a solid waste and a listed waste. The mixture rule is intended to discourage generators from mixing wastestreams. More information can be reviewed at 40 CFR 261.3(a)(iii) and (iv).

Is the solid waste subject to the mixture rule?

YES - the waste is subject to the mixture rule and is therefore regulated under RCRA Subtitle C.
NO - click here to go to Step #6 below.

• According to the Rule, any solid waste derived from the treatment, storage, or disposal of a hazardous waste is considered hazardous. "Derived from" wastes include sludges, spill residue, ash, emission control dust, and leachate. Some examples are drums that have been used for storage of a hazardous waste, or ash from the incineration of hazardous waste. This principle applies regardless of the actual risk to human or environmental health. More details about the "derived-from" rule and exemptions to the rule are included in 40 CFR Part 261.3 (c) and (d).

YES - the waste is subject to the derived-from rule and is therefore regulated under RCRA Subtitle C.
NO - the waste is not classified as hazardous under RCRA Subtitle C.