Proposed rule · 2026-05491

Standards for Air Curtain Incinerators That Only Burn Wood Wastes, Yard Wastes and Clean Lumber; Provision for Commercial and Industrial Solid Waste Incineration Units: Temporary Use Incinerators and Air Curtain Incinerators Used in Disaster Recovery

The U.S. Environmental Protection Agency (EPA) is proposing two separate and distinct actions under Clean Air Act (CAA) section 129. In the first action, the EPA proposes to consolidate the existing provisions governing air curtain incinerators (ACI) that only burn wood wastes, yard wastes, and clean lumber into one new rule subpart. Specifically, we are proposing to consolidate the opacity limitations and associated monitoring, recordkeeping, and reporting requirements that currently exist across various subparts for CAA section 129 source categories: large municipal waste combustors (LMWC), small municipal waste combustors (SMWC), commercial and industrial solid waste incinerators (CISWI), and other solid waste incinerators (OSWI). We are also proposing to remove the permitting requirement for this type of ACI that are not located at major sources or subject to federal permitting requirements for other reasons. The proposed removal would not cover ACI that are currently subject to OSWI or LMWC rules which have already been amended to remove such permitting requirements. In the second action, the EPA proposes to include in the CISWI rule subparts provisions for the temporary use of CISWI units to combust debris from a qualifying disaster or emergency on a temporary basis without complying with (CAA) section 129 requirements that would otherwise apply to CISWI units for the combustion of commercial and industrial waste during normal operations. These additional provisions would bring the CISWI rule subparts into alignment with existing OSWI provisions that allow such temporary use of OSWI units to combust debris from a disaster or emergency.