State safety inspectors visited the Valero refinery in Benicia on Thursday to investigate complaints by workers, NBC Bay Area’s Investigative Unit has learned. The workers said they were doused with dangerous chemicals during a flaring incident last Thursday. Thick, black smoke could be seen sh ooting out of the refinery from miles away. Several workers told the Investigative Unit that black liquid rained down on them for about five minutes at the start of the flaring. They said the incident sent about two dozen workers to the hospital with burns from caustic cleaning chemicals they were using to decommission the facility. NBC Bay Area reached out to both Valero and Cal-OSHA for more information but did not immediately hear back. Valero is scheduled to shut down its Benicia refinery at the end of the month. Benicia Mar 26 Black smoke and soot seen at Valero refinery in Benicia Benicia Jan 8 Valero will import refined gasoline after idling Benicia operations by April ...read more read less