On June 30, 2020, US EPA approved portions of the 2018 Plan for the 1997, 2006, and 2012 PM2.5 Standards and the San Joaquin Valley Supplement to the 2016 State Strategy for the State Implementation Plan related to the 2006 24-hour PM2.5 National Ambient Air Quality Standard (NAAQS) of 35 μg/m³. Additionally, EPA granted an extension of the Serious area attainment date for the 2006 PM2.5 NAAQS from December 31, 2019, to December 31, 2024. Federal review of portions of the plan that pertain to the other PM2.5 standards will continue in 2020.
The District adopted the 2018 Plan for the 1997, 2006, and 2012 PM2.5 Standards on November 15, 2018. This plan addresses the EPA federal 1997 annual PM2.5 standard of 15 μg/m³ and 24-hour PM2.5 standard of 65 μg/m³; the 2006 24-hour PM2.5 standard of 35 μg/m³; and the 2012 annual PM2.5 standard of 12 μg/m³. This plan demonstrates attainment of the federal PM2.5 standards as expeditiously as practicable.