Understanding Incineration: A Regulatory Overview
The definition of incineration in the U.S. is complex and carried out through different statutes and regulations. The definition – and regulatory treatment – varies depending on the legal context, statute, and purpose of the regulation.
The EPA defines incineration as: “The destruction of solid, liquid, or gaseous wastes by controlled burning at high temperatures. Hazardous organic compounds are converted to ash, carbon dioxide, and water. Burning destroys organics, reduces the volume of waste, and vaporizes water and other liquids the wastes may contain. The residue ash produced may contain some hazardous material, such as non-combustible heavy metals, concentrated from the original waste.”
The core concept of incineration – controlled flame combustion in an enclosed device – is consistent across statutes, but the specific regulatory definitions, context, and implications do differ based on statutory purpose and regulated material. So, while the basic idea of incineration doesn't change, each regulatory framework (RCRA, CAA, TSCA) treats it in distinct ways, leading to functionally different definitions and regulatory outcomes.
Regulatory Overview:
Under 40 CFR §260.10, the EPA defines an incinerator as:
"Any enclosed device that uses controlled flame combustion and does not meet the criteria for classification as a boiler, sludge dryer, carbon regeneration unit, or industrial furnace."
This definition is found in the context of hazardous waste regulations under the Resource Conservation and Recovery Act (RCRA).
In broader guidance materials, such as the EPA On-Site Incineration Technology Overview and RCRA training modules, incineration is described more functionally:
“Incineration is a controlled flame combustion process used to thermally degrade and destroy organic contaminants in waste materials. It converts hazardous organic substances into carbon dioxide, water vapor, and inert ash.”
Under RCRA, EPA regulates hazardous waste incineration as a form of treatment through design, performance, permitting, and operational standards outlined in 40 CFR Part 264, Subpart O. These regulations work in tandem with the Clean Air Act, which governs air emissions from incinerators by setting limits on hazardous air pollutants and ensuring proper emission controls. Additionally, under the Toxic Substances Control Act (TSCA), EPA regulates the incineration of specific toxic substances, such as polychlorinated biphenyls (PCBs), through strict operational and performance standards in 40 CFR § 761.70 to ensure the safe and complete destruction of highly persistent and bioaccumulative chemicals.
Clean Air Act – 42 U.S.C. § 7429: Solid Waste Combustion
Mandates EPA to establish performance standards and other requirements for various categories of solid waste incineration units, including municipal, medical, and commercial/industrial waste incinerators. It specifies emission limitations for pollutants such as particulate matter, sulfur dioxide, hydrogen chloride, nitrogen oxides, carbon monoxide, lead, cadmium, mercury, and dioxins/furans. The statute also outlines requirements for operator training, monitoring, and permitting of incineration units.
40 CFR Part 63, Subpart EEE – National Emission Standards for Hazardous Air Pollutants (NESHAP) for Hazardous Waste Combustors
This subpart establishes MACT standards for hazardous waste combustors, including incinerators, cement kilns, and lightweight aggregate kilns. It outlines emission limits, operating requirements, and performance testing procedures to control hazardous air pollutants
Resource Conservation and Recovery Act (RCRA)--42 U.S.C. § 6924: Standards for the Treatment, Storage, and Disposal of Hazardous Waste
Authorizes EPA to set performance standards for facilities that treat, store, or dispose of hazardous waste—including incinerators.
40 CFR Part 264, Subpart O—Incinerators, which set standards for:
Combustion efficiency
Destruction and removal efficiency
Emissions monitoring
Waste analysis
Closure requirements
Operator training and permitting
Toxic Substances Control Act (TSCA) – 15 U.S.C. § 2605: Governs Incineration of Specific Chemicals (e.g., PCBs)
40 CFR § 761.70 – Incineration of PCBs
Requires EPA approval for facilities handling PCBs, including combustion temperatures, emission limits, and monitoring protocols..
Sets design, operational, and emission control requirements for incinerators handling PCBs.
Under 40 CFR Part 60, EPA has established Standards of Performance for New Stationary Sources (NSPS) for various types of incinerators and combustion units that combust solid waste or hazardous materials. These subparts include:
Subpart CCCC: Applies to commercial and industrial solid waste incineration (CISWI) units.
Subpart DDDD: Covers emission guidelines for existing CISWI units
Subpart Ec: Pertains to hospital/medical/infectious waste incinerators.
Subpart Eb: Relates to large municipal waste combustors.
Subpart AAAA: Addresses small municipal waste combustors.
Subpart EEEE: Concerns other solid waste incineration units.