Summary
EPA is proposing to determine that the West Central Pinal County nonattainment area attained the 2006 24-hour national ambient air quality standard (NAAQS) for particulate matter with a diameter of 2.5 micrometers or smaller (PM2.5 or “fine particulate matter”) by December 31, 2017, the statutory attainment date for the area. The proposal is based on the three-year average of annual 98th percentile 24-hour concentrations for the 2015-2017 period, using complete, quality-assured, and certified PM2.5 monitoring data.
Action
Proposed Rule
Dates
Written comments must arrive on or before May 28, 2019.
For Further Information Contact
Jerry Wamsley (wamsley.jerry@epa.gov), EPA Region IX, (415) 947-4111