Monitoring by the state and Vistra will continue to watch for any risks to public health
MONTEREY -- On January 20, the U.S. Environmental Protection Agency (EPA) concluded supplemental air monitoring in the vicinity of the Vistra Energy battery power storage facility fire in Moss Landing, CA. Results for hydrogen fluoride and particulate matter showed no risk to public health throughout the incident, and smoke from the facility has greatly diminished. The EPA demobilized air monitoring operations after consultation with the Monterey County Incident Command for the Vistra fire.
EPA began monitoring for hydrogen fluoride, a highly toxic gas produced by lithium-ion battery fires, and for particulate matter after the fire began on January 16. The request for air monitoring came from Monterey County. As part of the multi-agency emergency response, EPA installed a total of nine monitoring stations shortly after the fire started. Two monitoring stations were located at the facility and four just outside the facility, including one at Moss Landing. Three monitoring stations were located in communities due east of the fire, to the south near Castroville, and to the north in the vicinity of Moss Landing Middle School. Monitoring stations were sited to account for changes in wind direction and potential drift to nearby communities.
EPA's monitoring showed concentrations of particulate matter to be consistent with the air quality index throughout the Monterey Bay and San Francisco Bay regions, with no measurements exceeding the moderate air quality level. Hydrogen fluoride gas was measured at one second intervals and there were no exceedances of California's human health standards.
In addition to EPA's monitoring, Vistra Energy brought in a third-party environmental consultant with air monitoring expertise, right after the fire started, to conduct roaming and fixed air monitoring in communities. Air monitoring stations have been installed where EPA's stations had been located to continue air monitoring as the response progresses. An air monitor location map is located at the County's incident website. The Monterey Bay Air Resources District also monitors particulate matter through their regulatory air monitors and wildfire smoke sensors.
Throughout the response, EPA has shared air monitoring data with state and local officials to inform public health decisions, including North Monterey County Fire, Monterey County Environmental Health, and Cal Office of Environmental Health Hazard Assessment. Information is being posted at:
www.countyofmonterey.gov
www.readymontereycounty.org
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