Overview
- In a Monday filing, the EPA urged the D.C. Circuit to vacate the 2024 PM2.5 limit of 9 micrograms per cubic meter and rule before the Feb. 7 area-designation deadline.
- If the court grants the request, the national standard would revert to the prior 12 micrograms level as the agency prepares a replacement proposal early next year.
- The filing echoes arguments from industry groups and 25 Republican-led states about compliance costs and permitting impacts, with EPA officials citing potential costs in the hundreds of millions to billions.
- The Biden-era rule was projected to prevent up to 4,500 premature deaths in 2032 and yield major health benefits, particularly for communities facing disproportionate pollution burdens.
- Environmental and public-health advocates condemned the move as unprecedented and pointed to a 2001 Supreme Court ruling that they say bars factoring costs into National Ambient Air Quality Standards.