PM Planning
The following documents are available for public review:
Particulate Matter (PM) and PM Planning: Frequently Asked Questions
Webcast
BAAQMD Particulate Matter (PM) Planning Activities
There are State and national air quality standards for both PM10 (particles smaller than 10 microns in diameter) and PM2.5 (particles smaller than 2.5 microns in diameter). PM levels in the Bay Area have been reduced significantly in recent years, as documented in the report entitled Trends in Bay Area Ambient Particulates. However, despite significant progress in reducing PM levels in recent years, the Bay Area does not yet attain all the PM standards.
National 24-Hour PM2.5 Standard
In 2006 the U.S. EPA lowered the 24-hour PM2.5 national standard from 65 µg/m3 (micro-grams per cubic meter) to 35 µg/m3. Areas designated as non-attainment pursuant to the revised 24-hour PM2.5 standard are required to prepare a State Implementation Plan (SIP) submittal to EPA by fall 2012 to demonstrate how they will attain the standard by December 2014. EPA designated the Bay Area as nonattainment for the PM2.5 standard in December 2009 based on PM2.5 monitoring data for the three-year period 2006-2008. However, Bay Area PM2.5 levels have declined in the past several years. Monitoring data for 2008-2010 shows that the Bay Area met the 24-hour national PM2.5 standard during this period.
Current PM Planning Activities
Based on the Bay Area PM2.5 monitoring data for years 2008-2010, on December 8, 2011 the California Air Resources Board (ARB) submitted a “clean data finding” request to US EPA on behalf of the Bay Area. If the clean data finding request is approved, then EPA guidelines provide that the region can fulfill federal PM2.5 SIP requirements either by preparing:
- a redesignation request and a PM2.5 maintenance plan, or
- a “clean data” SIP submittal
Because peak PM2.5 levels can vary from year to year based on natural short-term changes in weather conditions, the Air District believes that it would be premature to submit a redesignation request and PM2.5 maintenance plan at this time. Therefore, the Air District will prepare a “clean data” SIP to address the required elements, including:
- An emission inventory for primary PM2.5, as well as precursors to secondary PM formation; and
- Amendments to the Air District’s New Source Review (NSR) regulation to address PM2.5.
The Air District is committed to reducing the impacts of PM on public health and the climate. Therefore, in addition to preparing a “clean data” SIP to fulfill EPA requirements, Air District staff will develop a comprehensive PM research agenda to guide our long-term efforts to reduce this important air pollutant. This (non-SIP) PM research agenda will complement the “clean data” PM2.5 SIP. Air District staff is working to develop both the “clean data” PM2.5 SIP and the companion PM research agenda by summer 2012.
In September 2010, the Air District adopted the Bay Area 2010 Clean Air Plan which defines an integrated, multi-pollutant air quality control strategy. The Air District is working to implement the 55 control measures in the 2010 Plan; many of these measures will reduce will reduce direct emissions of PM, precursors that contribute to formation of ozone and secondary PM, toxic air contaminants, and greenhouse gases.