The Bay Area’s most-fined air polluters: Explore 10 years of environmental violations

On Feb. 1, 2025, a fire at the Martinez Refining Company (MRC) released toxic byproducts for three days, prompting Contra Costa County health officials to issue a health advisory for nearby residents. 

Four days later, the Bay Area Air District, the public agency responsible for enforcing air quality laws in the region, issued three violation notices to MRC, the second largest oil refinery in the Bay Area. Two months later, the district added 27 infractions to the list, ranging from permit violations to excessive flaring (the intentional burning of natural gas during oil production). 

The violations were among 323 amassed by MRC, which is owned by PBF Energy, over the last decade. Altogether, they resulted in $741,500 in penalties incurred by the company, according to air district data analyzed by Richmondside. 

While significant, those fines are a pittance compared to what the air district has levied against other large-scale polluters over the last decade. According to district records obtained by Richmondside, the agency assessed nearly $122 million in fines stemming from more than 10,000 notices of violations issued between 2015 and 2025. The types of violations ranged from the rare $100 fine to people burning wood on Spare the Air days to a historic $82 million settlement with an oil refinery that’s now set to close. 

While catastrophic accidents like fires at big oil refineries or scrap metal recyclers are often associated with major polluting events, the air district has also levied fines against cities, hospitals, waste management companies, auto body shops, dairy farms, and even state agencies such as the  California Highway Patrol, the state Department of Water Resources, and the Department of Transportation, which have offices in the Bay Area.

The fines are of public interest in part because the air district uses the millions of dollars it collects from fines and settlements to pay for initiatives that address air quality impacts, improve public health and advance environmental justice, according to its website. The first round of grants under the district’s new Local Community Benefits Fund will focus on Benicia and Richmond, two cities with large oil refineries. 

According to air district officials, the agency is most likely to discover people and businesses polluting the air through its own routine inspections of permitted businesses and industries, and from complaints filed by residents. 

“Complaints come in of observations of various air quality issues, odor, dust, smoke, you name it,” said Edward Giacometti, a manager with the air district’s compliance and enforcement division. “Staff is going to investigate those complaints. If there’s a violation of a law or anything in those cases that’s determined through that investigation, action will be taken in the form of a notice of violation.”

Air district investigators attempt to determine not only the violation that occurred, but what caused it. Was it a choice by the facility? A lack of training? A mechanical failure? Once a violation is confirmed by the district, a fine is levied with the amount being determined by the severity of the incident, the compliance history of the offending party, and other factors.

“If we’ve had a continual recurrence of something — multiple events where there’s something bigger there — that’s when we want to combine and look at those from that evaluation,” Giacometti said. 

Valero, Chevron and Tesoro were fined the most

Nearly all of the biggest fine-payers over the 10-year period we examined are intertwined with the automobile and fossil fuel industries, and three of the Bay Area’s five oil refineries top the list.

The Valero refinery in Benicia was fined the most, by far — nearly $82 million — and still had 270 outstanding alleged violations, as of this writing. 

Chevron Richmond was penalized more than $15 million over the last decade, including a settlement to address nine violations related to air monitoring for $900,000. It had 338 alleged violations still pending as of mid-December. (These air district fines do not include Chevron’s $550 million settlement reached in 2024 with the city of Richmond, to be paid out over a 10-year period.)

Tesoro, which owns a refinery in Martinez, was fined nearly $9 million over the last decade, with 50 alleged violations still outstanding. 

Chevron, Marathon, ARCO, Phillips 66, Shell, Exxon and Mobil also received fines from the air district stemming from violations at their branded gas stations, although those amounts were much lower.

In fourth place on the Bay Area Air District’s top-paying polluter list is Chemtrade West, an industrial chemical company whose products are used in the oil refining process by Chevron, their nextdoor neighbor in Richmond. Chemtrade was fined nearly $1.3 million over the last decade, the bulk of which went to settling seven violations that were announced in July 2023, involving the facility’s continuous emissions monitoring system, which the air district said underreported sulfur dioxide emissions by an estimated 33% over multiple years.

In September, Chemtrade agreed to pay the air district an additional $160,000 for failing to maintain emergency equipment and being late to report violations. Some of those violations dated back to 2013.   

In the fifth spot is the Schnitzer Steel Products Company in Oakland, now known as Radius Recycling, which crushes cars and trucks, among other metals. It was issued a combined $903,750 in fines, most of that stemming from fires in 2018, 2020, and most notably in August 2023, when a fire sent plumes of noxious black smoke from its West Oakland facility. 

The following July, Radius and two of its senior employees faced criminal charges after being indicted by an Alameda County grand jury. District Attorney Ursula Jones Dickson eventually dropped the charges, saying there wasn’t enough evidence to convict. But Jones Dickson’s office and the air district later announced a joint lawsuit against Radius for violating several air district regulations, on top of its three pending violation notices, and for being a “public nuisance” due to the smoke from the 2023 fire.

Not even electric cars are immune from enforcement by the air district; Tesla, the EV giant whose original production facility is in Fremont, was eighth among the top paying polluters. 

Between 2015 and 2025, Tesla’s factory in the South Bay was cited 374 times. Most of these were for alleged violations of the Clean Air Act, constructing without permits, and reporting violations late. For those, the company was slapped with $502,500 in fines, with 328 alleged violations still pending as of mid-December 2025.

Rounding out the top 10 paying polluters are Vulcan Materials, the largest producer of construction materials in the U.S., whose locations in San Rafael, Petaluma and Pleasanton were penalized a combined $233,250 for five violations that included denying an air district inspector access to a site; and the Mariposa Energy Project (MEP), which uses natural gas to generate electricity in northeastern Alameda County. MEP was fined $209,000 for 16 violations, most of which were for emitting excess nitrogen oxide, a gas that can contribute to health ailments and cause environmental damage.

Why we wanted to examine and publish this data

During our newsroom’s more than a year-long reporting project looking into air quality in Richmond, we wanted to find out how the Bay Area Air District uses its regulatory muscle to cite and fine local polluters, at a time when scrutiny over local air pollution and its health and climate impacts has arguably never been higher. 

State legislation in recent years, most notably AB 617, which became law in 2017 and created the Community Air Protection Program, has given communities in California hit hardest by air pollution — including in Richmond, North Richmond and San Pablo — more resources to measure pollution in their air and form task forces to address it. And there’s an urgency to these public health efforts: Specialists with the California Air Resources Board, the state’s main regulating agency for air quality, have told Bay Area Air District leaders that getting permitted businesses back into compliance with emissions regulations “could create healthier air immediately.”

But for most members of the public, getting a clear picture of the totality of the air district’s enforcement efforts over time isn’t straightforward or easy to do. Since 2023, the Bay Area Air District has operated a search engine on its website making it possible for people to look up violation notices by keyword, location, and the timeframe in which a notice was issued. But those records only go back to 2021 and don’t include a written description of the alleged violation.

We wanted to examine enforcement data over a longer period of time, to get a broader look at which companies have been fined the most frequently, and to see how long violations can sometimes go unresolved. It took months of records requests by this reporter to gather, parse and sort through the raw data we received from the air district showing this information for the past decade. The dataset we received contains 10,253 notice of violation records, issued from January 2015 to mid-December 2025. 

Having access to data showing where air pollution has occurred in communities matters because there is ample scientific research showing exposure to polluted air can lower a person’s quality of life and increase the likelihood of chronic diseases like asthma and lung disorders that can shorten the lifespan. 

In Richmond, the neighborhoods most impacted by air pollution are those closest to Chevron, the rail lines that service the refinery and nearby industry, and the highways that are a source of harmful emissions from gas- and diesel-burning vehicles. Richmondside created a narrated video identifying these areas in a report last year.

Knowing where and how much the air district collects in fines is also in the public’s interest, as the agency adopted a policy in 2024 that says a portion of the money must be reinvested in communities impacted by pollution. For example, $64 million of an $82 million settlement reached in 2024 with Valero in Benicia — the largest in the air district’s history to date — are to be returned to the community for projects aimed at reducing or mitigating the effects of air pollution. The penalties assessed to the oil company were for unreported harmful organic compounds emissions from a hydrogen system detected in 2019, but the air district says the refinery knew about this as far back as 2003. (Valero announced earlier this year it plans to shut down its Benicia refinery.)

Some violation notices go unresolved for years

At the time the air district records were released to Richmondside, there were more than 3,300 pending notices of violation (NOV) — roughly a third of all notices issued during the 10-year span. Some were only days old, but more than two-thirds had been pending for at least a year. More than 300 were five years old or older, with some still lingering a full decade after being issued. 

Air district officials acknowledged a serious backlog of pending violations to the UC Berkeley news outlet Richmond Confidential in 2024, saying new leadership was working to get through those fines.

Alexandra Kamel, senior assistant council for enforcement with the air district, said a violation notice is marked pending from the moment it’s issued and stays that way until there’s a resolution, usually when a fine is levied or the violation is dismissed. 

“There’s a lot of steps that happen in between, because we can’t just settle the next day after an NOV is issued,” she said. “The process of investigation can be lengthy, especially for really serious violations.”

Once an investigation is complete, the air district’s legal department takes over. But alleged polluters and their attorneys don’t just get to wait out the clock to push potential penalties down the road, as the law allows the air district to collect increased penalties later. 

“That allows us to basically say, ‘You’re not going to profit and save money and get all this interest on the money.’ If they’re dragging out the process, and then, ultimately, we do settle, they’re not going to benefit from doing that,” Kamel said. “It’s never our intent to let NOVs be out there that long, and that’s something that we have been improving on over time.”

The East Bay’s five oil refineries are among the polluters with the highest number of pending notices. Chevron in Richmond had the most with 338 and Phillips 66 had 320 as of December 2025, with many pending for eight or more years. The latter had paid just $99,400 in fines incurred at its Rodeo refinery in the last decade. 

Tesla had 328 alleged violations marked pending, as of mid-December. 

Giacometti said there’s no cookie-cutter way to approach alleged air pollution violations, which is why many take so much time to find a resolution. 

“When an item says pending, there’s still movement happening, but there could be some situations where it’s going to take more investigative information and process to then establish a better case and a stronger case,” Giacometti said. “Each situation, while it may appear similar on the face of it, the cause and the background behind it may differ.” 

Big companies, such as those who own oil refineries in the Bay Area, have teams of lawyers dedicated to reducing their liability when the air district dings them, often settling multiple violations at one time. 

Some recent settlements with the air district include: Richmond garbage collection company Republic Services agreeing to pay $159,000 to settle 14 violations for methane leaks at its Petaluma landfill; Tesoro paying $372,500 for 13 violations at its Martinez refinery; and another Tesoro agreement to pay $75,000 while also improving its air monitoring and transparency. (The refinery has since switched to producing biofuels under the name Marathon Renewables.)

In late December, the air district announced that the Martinez Refining Company had agreed to pay $20,000 and improve the air monitors around its facilities, after the air district demanded all five Bay Area oil refineries adhere to stricter air monitoring standards. 

Individuals rarely pay for not sparing the air

Over the last decade, the air district has issued about 460 violation notices to residents for burning wood on Spare the Air days. Those rarely resulted in an actual fine, bringing in a total of $4,300 over a decade. If the air district demanded someone pay a fine, it was most often $100, but four times residents were fined $500. 

“With Spare the Air violations, we take them very seriously, but they’re usually individual people. It’s usually like a short duration of a violation,” Kamel said. “Maybe they’ve only done it once, and so then they have an option to take a class, and then the next time the penalty is higher.”

The district’s protocol is to first send the alleged violator a packet informing them of their violations. 

“Giving them that information we found has been very helpful, because then it clarifies the situation. It gets them to be more knowledgeable of the process, looking into the Spare the Air days,” Giacometti said. “You want to be able to give them that opportunity to be aware of the situation.”

This reporting was supported by the Fund for Investigative Journalism.