The Environmental Protection Agency (EPA or the ``Agency'') is proposing approval of a request submitted by the Colorado Department of Public Health and Environment (CDPHE) on June 27, 2022 for delegation of authority to implement and enforce Federal Plan Requirements for Hospital/Medical/Infectious Waste Incinerators (HMIWI) Constructed On or Before December 1, 2008 (the Federal Plan), within the state of Colorado. The Federal Plan establishes emission limits and monitoring, operating, and recordkeeping requirements for HMIWI units constructed on or before December 1, 2008, or modified on or before April 6, 2010. A Memorandum of Agreement (MOA) was signed on July 21, 2022 by the CDPHE Air Pollution Control Division Director, Michael Ogletree. This MOA constitutes the mechanism for the transfer of authority from the EPA to CDPHE. The MOA became effective upon signature by Regional Administrator, KC Becker, on August 8, 2022. The MOA delineates policies, responsibilities, and procedures by which the Federal plan will be administered and enforced by the CDPHE, as well as the authorities retained by EPA. The MOA and the request letter are included in the docket for this action. Accordingly, EPA is proposing to approve CDPHE's submittal in accordance with the Clean Air Act (CAA).