EPA Updates Clean Air Act Standards Applicable to Small Waste Incinerators
On June 30, 2025, the U.S. Environmental Protection Agency (EPA) finalized updates to its New Source Performance Standards (NSPS) and Emission Guidelines for Other Solid Waste Incineration (OSWI) units under the Clean Air Act (CAA). These units — combustion systems that incinerate solid waste from commercial or institutional sources not otherwise regulated under specific incinerator categories — include very small municipal waste combustors and institutional incinerators. The final rule includes applicability-related and definitional changes expanding the class of incinerators subject to NSPS, revises the OSWI subcategories and tightens emission limits for key pollutants. It also adopts changes to startup, shutdown, and malfunction (SSM), and expands testing, monitoring, reporting, and recordkeeping requirements that will affect both existing and new OSWI units.
Presidential Exemption for Certain Stationary Sources of Air Pollution
The Environmental Protection Agency (EPA) has opened an electronic mailbox to allow regulated sources to request a Presidential Exemption under section 112(i)(4) of the Clean Air Act (CAA) from nine National Emission Standards for Hazardous Air Pollutants (NESHAPs) that EPA is reconsidering (see table below) across the energy, manufacturing, and chemical sectors.
