In this action, the Administrator is proposing to find that lead air pollution may reasonably be anticipated to endanger the public health and welfare within the meaning of section 231(a) of the Clean Air Act. The Administrator is also proposing to find that engine emissions of lead from certain aircraft cause or contribute to the lead air pollution that may reasonably be anticipated to endanger public health and welfare under section 231(a) of the Clean Air Act. Written comments must be received on or before 17 January 2023. POC is Marion Hoyer, Office of Transportation and Air Quality, Assessment and Standards Division (ASD), EPA; Tele: (734) 214-4513; Email: hoyer.marion@epa.gov. (Federal Register 17 October 2022 [Proposed Rules] Pages 62753-62781).