Criteria for the Definition of Solid Waste and Solid and Hazardous Waste Exclusions

Proper waste management is an essential part of society’s public and environmental health. The Resource Conservation and Recovery Act (RCRA), passed in 1976, created the framework for America’s hazardous and non-hazardous waste management programs. Materials regulated by RCRA are known as “solid wastes.” Only materials that meet the definition of solid waste under RCRA can be classified as hazardous wastes, which are subject to additional regulation. EPA developed detailed regulations that define what materials qualify as solid wastes and hazardous wastes. Understanding the definition of a solid waste is an important first step in the process EPA set up for generators to hazardous waste to follow when determining if the waste they generated is a regulated hazardous waste.

Some of the materials that would otherwise fit the definitions of a solid or hazardous waste under waste identification are specifically excluded from the definitions. EPA concluded that these materials should not be regulated as solid or hazardous wastes for a number of reasons. Many exclusions are mandated in RCRA. EPA selected other exclusions to provide an incentive to recycle certain materials, because there was not enough information on the material to justify its regulation as a solid or hazardous waste, or because the material was already subject to regulation under another statute.

What is a Solid Waste?

State regulatory requirements for generators may be more stringent than those in the federal program. Be sure to check your state's policies.

RCRA states that "solid waste" means any garbage or refuse, sludge from a wastewater treatment plant, water supply treatment plant, or air pollution control facility and other discarded material, resulting from industrial, commercial, mining, and agricultural operations, and from community activities. Nearly everything we do leaves behind some kind of waste.

It is important to note that the definition of solid waste is not limited to wastes that are physically solid. Many solid wastes are liquid, semi-solid, or contained gaseous material.

A solid waste is any material that is discarded by being:

• Abandoned: The term abandoned means thrown away. A material is abandoned if it is disposed of, burned, incinerated, or sham recycled.
• Inherently Waste-Like: Some materials pose such a threat to human health and the environment that they are always considered solid wastes; these materials are considered to be inherently waste-like. Examples of inherently waste-like materials include certain dioxin-containing wastes.
• A Discarded Military Munition: Military munitions are all ammunition products and components produced for or used by the U.S. Department of Defense (DOD) or U.S. Armed Services for national defense and security. Unused or defective munitions are solid wastes when:
  • abandoned (i.e., disposed of, burned, incinerated) or treated prior to disposal;
  • rendered nonrecyclable or nonusable through deterioration; or
  • declared a waste by an authorized military official.
    Used (i.e., fired or detonated) munitions may also be solid wastes if collected for storage, recycling, treatment, or disposal.

  Materials that do not meet this definition are not solid wastes and are not subject to RCRA regulation.

  Wastes Excluded from Solid Waste Regulation

  The 2018 Definition of Solid Waste Final Rule updates some the exclusions found in the table below.

  Several materials are excluded from the definition of solid waste. These materials are excluded for a variety of reasons, including public policy, economic impacts, regulation by other laws, lack of data, or impracticability of regulating the waste. The decision to exclude the following materials from the solid waste definition is a result of either Congressional action (embodied in the statute) or an EPA rulemaking.

  A material cannot be a hazardous waste if it does not meet the definition of solid waste. Thus, wastes that are excluded from the definition of solid waste are not subject to RCRA subtitle C hazardous waste regulation. Read more on our Regulatory Exclusions and Alternative Standards webpage.

  The table below contains a description of wastes which are excluded from the definition of solid waste and the subsection of 40 CFR section 261.4(a) where you can find more information about the exclusion.

  Domestic Sewage and Mixtures of Domestic Sewage