Randall Baxter – Air Quality Specialist – Trinity Consultants

In September of 2021 the South Coast Air Quality Management District (SCAQMD) completed five years of the most extensive hexavalent chromium air monitoring program in the world in the city of Paramount, California (the City). Since then, the City has assumed the effort, with the City’s mayor stating that “voluntary air monitoring reaffirms the City’s commitment to transparency and the health and safety of the Paramount community.” This ongoing monitoring effort includes taking 1-in-6-day air samples at five locations throughout the City to monitor levels of hexavalent chromium, with the addition of a meteorological monitoring at City Hall.In order to continue the operation of the network in an effective manor after transitioning from the SCAQMD monitoring, upgrades were implemented to improve sampling uptime and reporting. This was achieved by keeping tighter criteria for sampler calibration, adding solar charging systems to the pole monitoring systems, upgrading the sampler power systems. In addition to displaying the data through a data visualization, results of the sampling are uploaded and reported to the public in less than a week. The monitoring network ran into the challenges of the Covid pandemic. Most critical were supply chain issues for the samplers originally used in the network. In order to address these issues a comparison study to verify the comparability of data collected by other makes and models of samplers was conducted. This comparison was based upon the colocation method done for most EPA acceptance testing. Both samplers used were ran for the same monitoring site and the samples were analyzed for through the same lab. This provided the City options when addressing sampler failures in a timely manner to ensure maximum data recovery.