CARB (Finally) Finalizes SNAPS Report for Lost Hills, a Clear Win for Facts & Fairness

The California Air Resources Board (CARB) has released its Final Report for the Study of Neighborhood Air near Petroleum Sources (SNAPS) project in Lost Hills, California, concluding nearly a year of intensive air monitoring conducted between May 2019 and April 2020. The community, located near the Lost Hills Oil Field, was the first to undergo this detailed analysis as part of CARB’s ongoing SNAPS program.

The study measured more than 200 pollutants using both stationary and mobile monitoring equipment. CARB’s findings confirm that air quality in Lost Hills is generally comparable to other Central Valley communities, with criteria pollutants meeting state and federal air quality standards throughout the study period.

While the study detected higher concentrations of acrolein, a compound for which no clear source has been identified, CARB explicitly acknowledged that mobile sources, such as diesel trucks and regional transportation corridors, were responsible for the majority of black carbon and diesel particulate matter, which accounted for roughly 65% of the estimated cancer risk. The Final Report also clarified that oil and gas operations contributed to only a portion of volatile organic compounds (VOCs) and approximately half of BTEX (benzene, toluene, ethylbenzene, and xylene) levels, with cumulative cancer risk estimates similar to other San Joaquin Valley sites not directly associated with oil and gas production.

This outcome represents a significant validation of CIPA’s technical engagement and advocacy during the review process. In its comments on the Draft Report, CIPA challenged CARB’s premature attribution of pollutant increases to oil field activity, pointing out that several other significant emission sources, including agriculture, traffic from SR 46 and I-5, a landfill, and a wastewater treatment facility, had been overlooked.

CARB’s Final Report reflects these CIPA-driven corrections, incorporating new maps that accurately depict these sources in proximity to the monitoring site and acknowledging that the selected location is influenced by multiple industrial, transportation, and agricultural activities. Moreover, CARB retained CIPA’s recommended cautionary statement that the source apportionment results “should be used with caution, and all caveats should be considered prior to interpretation of the results.”

CIPA appreciates CARB’s willingness to address these key concerns and ensure that the Final SNAPS report for Lost Hills presents a balanced, science-based assessment of local air quality.

For CIPA members, the takeaway is clear: facts prevailed. Objective data—not assumption—now frame the conversation around air quality near oil and gas operations in the Central Valley.