Regulator alleges continued violations at Valero Benicia refinery

BENICIA – The Bay Area Air Quality Management District announced Thursday that it had discovered continued violations at the Valero Benicia refinery during its investigation into years of toxic releases.

Specifically, the air district said that Valero had failed to install required pollution control equipment on eight pressure relief devices,  safety devices that prevent extreme over pressurization that could cause a catastrophic equipment failure. The violations led to 165 tons of illegal emissions, the air district said.

The air district said it is seeking an abatement order from its independent hearing board that would require Valero to immediately correct the violations.

“The extensive violations discovered at Valero's Benicia refinery are of great concern,” air district chief counsel Alexander Crockett said in a statement. “Our priority is to protect the health and well-being of our communities, and we will vigorously pursue enforcement measures to achieve cleaner and safer air for all residents of the Bay Area.”

A Valero spokesperson did not immediately respond to a request for comment.

Benicia Mayor Steve Young said in a statement that Valero's alleged continued pattern of emissions violations is "particularly concerning" and "should bother all Benicia residents."

"The City is also waiting, with increasing impatience, to see how the separate, bigger, case of 16 years of unreported hydrogen emissions will be ultimately resolved," Young said. "The citizens of Benicia deserve much more transparency from the refinery about these operational deficiencies than we have been receiving."

The air district discovered the violations during its investigation into the release of toxic emissions from a hydrogen vent at the refinery that went on for nearly 20 years. The air district separately obtained an abatement order for those violations last year, though by the time it revealed the excess emissions publicly, it had already worked with Valero to correct them for some time.

Those excess emissions were first detected by Valero in 2003 when it started measuring output from the hydrogen vent, but the air district believes it likely had been going on even earlier and has no measurements from that time.

Since 2003, the air district estimates that the vent was releasing about 4,000 pounds of hydrocarbons per day, far more than state regulations allow. Overall, the district found that Valero released more than 10,000 tons of excess hydrocarbons over 16 years, including 138 tons of toxic air contaminants ethylbenzene, tolyrene, zolerine and the especially carcinogenic benzene.

When the air district discovered the excess emissions in 2019, it didn’t report its findings publicly, working with Valero to fix the problem for nearly two years before disclosing it to city leaders and the community. That has led to criticism that the air district wasn’t being transparent.

Following the discovery, Valero made a change to its process where it recycled the hydrogen, which resulted in a 70% reduction in emissions in 2020 and a 98% reduction in 2021, nearly bringing the refinery into compliance, according to the air district.

But many Benicia community members objected to the air district withholding information about the emissions for so long. The city has long had a troubled relationship with the refinery, which has repeatedly attempted to influence its elections to prevent environmentalist candidates from taking office.

For the latest violations, air district officials said that Valero had failed to report emissions from its pressure relief devices for over 10 years as required. Valero's failure to add required equipment to the pressure relief devices resulted in 55 further releases from eight devices, amounting to 165 tons of illegal organic compound emissions, according to the air district.

The refinery is one of five oil refineries in the Bay Area and processes 170,000 barrels — approximately 7 million gallons — of crude oil per day. Valero purchased the refinery from ExxonMobile in 2000 and has operated it since.

Editor's note: This story has been updated to add information about how much pollution was allegedly released because of the violations and a statement from Benicia Mayor Steve Young.