U.S. EPA Says No to CO NAAQS Revision

U.S. EPA has proposed to retain the National Ambient Air Quality Standards (NAAQS) for carbon monoxide (CO) after a review of the most current scientific data for that pollutant. The current NAAQS levels for CO are 9 parts per million (ppm) on an 8-hour average and 35 ppm on a 1-hour average. In addition to retaining the NAAQS levels, U.S. EPA is also proposing to bolster the current CO ambient monitoring network by installing 77 ambient monitors in 53 urban areas that are located primarily near heavily trafficked roadways. The ambient monitoring network will be used to inform U.S. EPA’s next review of the CO NAAQS. Companies have had to directly demonstrate compliance with the CO NAAQS if they trigger major source permitting for a proposed project. Demonstrating compliance is typically not a difficult demonstration and usually does not impact the design and feasibility of a major air permitting project.