Monitoring Air Quality in California’s San Joaquin Valley

CSS employee owners supported the deployment and operation of the U.S. Environmental Protection Agency (EPA) air quality monitoring trailer (WEAVE COM – Western Enhanced Air quality VEhicle for COmmunity Monitoring) in California’s San Joaquin Valley in during late fall and early winter of 2024.  Elevated particulate matter (PM_2.5) is frequently found throughout the valley during the wintertime when thermal inversions trap pollution. Instruments on the trailer measure criteria air pollutants, other airborne contaminants and the chemical composition of particulate matter.  The mobile lab allows scientists to collect atmospheric data to fill in gaps between existing fixed air quality monitoring stations to help identify sources and types of atmospheric PM_2.5. CSS staff helped set up the trailer at the deployment site, conducted daily quality control checks on multiple instruments, and supported instrument operations throughout the deployment.