EPA promulgated emissions standards for Other Solid Waste Incineration (OSWI) units on December 16, 2005. Units covered under this rule include certain very small municipal waste combustion and institutional waste incineration units. On September 14, 2018, the U.S. District Court for the District of Columbia ordered EPA to “review and revise” the OSWI standards and guidelines and publish a notice of proposed rulemaking by August 31, 2020, and promulgate a final rule by May 31, 2021 (later extended to March 1, 2024). EPA is finalizing this action under the statutory requirement of CAA section 129(a)(5) to review and revise the OSWI standards and guidelines. This final action reflects feedback and consultations with the State of Alaska and Tribal representatives, including a webinar, informational meetings, consultation letters, and government-to-government consultations. The Agency heard that many of the rural tribal communities in Alaska use rudimentary designed incineration units, have limited financial resources and limited access to haul waste to a larger community.