EPA Announces Retention of Existing Particulate Matter Standards
During a press conference yesterday, December 7, 2020, EPA Administrator Wheeler announced the Agency’s determination to retain the existing National Ambient Air Quality Standards (NAAQS) for particulate matter (PM). The decision to retain existing standards, that were last reviewed in 2012, comes after careful consideration of the most recent available scientific evidence and technical data, consultation with the Agency’s independent scientific advisors, and consideration of more than 60,000 public comments on the proposal.
The standards being retained include the existing primary (health-based) and secondary (welfare-based) NAAQS for both fine (PM2.5) and coarse (PM10) particulate matter. Fine particles can be emitted directly from a variety of sources, including vehicles and fires. PM2.5 can also be formed when gases emitted by power plants, industrial processes, and gasoline and diesel engines react in the atmosphere. Coarse particles include road dust, agricultural operations, construction and demolition operations, industrial processes, and biomass burning.
Had the standard been revised, it would have triggered a cascade of updates to federal and state air programs. Beginning with redesignation of attainment and nonattainment areas, followed by updates to State Implementation Plans (SIP), and finally leading to revisions with state regulations and permits to progress toward meeting the new standards. With the announcement to retain PM standards at the current levels, regulated sources and regulators will continue working toward the existing standard attainment.