In March, Valero's Benicial refinery spit out pollution which caused city officials to warn residents to stay indoors. The Bay Area Air Quality Monitoring District sent a van to monitor the situation because currently there is no stationary air quality monitoring device in the residential areas despite the fact that it's home to one of the largest refineries in California.
As explained in the article "Valer's March Pollution Release Exposes Weaknesses in Benicia's Air Monitoring System" by Ted Goldberg:
Benicia's mayor, along with a leading air quality expert and two local environmentalists, say these most recent releases confirm that the small North Bay city needs a more robust and coordinated strategy to measure what gushes out of its largest employer.
"It seems that right now, if there's an incident, what happens is folks kind of drive around and see if they can catch the plume," said Anthony Wexler, director of the Air Quality Research Center at UC Davis.
Read more about the city's response and the BAAQMD monitoring efforts in the article below: