A “cat cracker” may sound like a child’s snack, but call it by its full name — fluidized catalytic cracking unit — and it is obviously something far different. Cat crackers are a central piece of refinery equipment that turns crude oil into gasoline, diesel and aviation fuel. Regulating this specialized equipment, referred to by the acronym FCCU, recently resulted in unusually high public participation in a significant Bay Area Air Quality Management District decision.
Reducing pollution is challenging for refineries. Crude oil is a complex mixture of hydrocarbons, which is why it can be split into other products. In addition, it usually contains varying amounts of sulfur, nitrogen, oxygen and various metals, so refining it generates toxic compounds and particles which must be controlled. Refineries are subject to a multitude of regulations to prevent pollution reaching the environment and affecting the community.
FCCUs are responsible for over 50 percent of the particulate matter from refineries — over 800 tons per year — and 17% of particles 10 microns or less in diameter (PM10) from facilities with Air District permits in the region. The Air District’s Rule 6-5, regulating FCCUs in the Bay Area, was first adopted in 2015, because improved federal testing methods showed “scrubbed” FCCU emissions combining with the atmosphere when released to form more particulates than previously thought. Particulate matter often doesn’t travel far and therefore has its greatest impact on adjacent, disadvantaged communities. Janet Hashe from Atchison Village near the Chevron refinery told the Air District Board in June, “The effects of air pollution are disproportionate on these communities and have been for decades. . .”
Under a recent state law, the Air District must require the Best Available Retrofit Control Technology for pollution sources at facilities that impact disadvantaged communities. Rule 6-5 was revised in July in accordance with this law. It will affect up to three of the region’s five refineries: Chevron, PBF (formerly Shell) and the currently inactive Marathon. Phillips 66 doesn’t use an FCCU at its Bay Area facility, and Valero recently installed a wet gas scrubber which should enable it to comply with the updated regulation.
Rule 6-5 now requires refineries to meet more stringent standards for emissions of sulfur dioxide and ammonia. It also sets a new limit on PM10 to reduce these emissions by over 400 tons/year. An agency staff report advised the Board that to reach that standard, local refineries will probably need to use wet gas scrubbers. This technology is used in other refineries across the country in addition to Valero.
The extensive debate over the draft rule, which started in 2019, also considered a more lenient standard that would allow twice as much PM10. Refineries might be able to meet that lower standard with less expensive electrostatic precipitators. During the multiple workshops and detailed discussion by the agency’s staff and Board subcommittees prior to two lengthy Board hearings, the two alternatives were nicknamed .10 and .20, based on the technical definition of how the PM10 output is measured, with .10 being the most stringent. They were also referred to as the ESP (electrostatic precipitator) and WGS (wet gas scrubber) alternatives.
The more lenient .20 standard was potentially easier to achieve, and would have gone into effect by January 2023, while the adopted .10 standard won’t go into effect until January 2026. Although it will take longer to affect the region’s environmental quality, the long-term impact will be greater. Staff estimates show a yearly health benefit in reduced deaths, respiratory disease and cardiac illness of approximately $26-60 million, while the rejected alternative would have achieved only $17-38 million.
Long-term health benefits were the deciding factor for the district’s Stationary Source and Climate Impacts Committee when it voted to send the .10 alternative to the board as the recommended update to the rule. Health effects were also cited by a majority of the organizations and individuals who supported the more stringent alternative during board hearings. As Sally Tobin from Richmond noted at the six-hour June hearing, “Richmond children are hospitalized for asthma twice as often those in other parts of Contra Costa.” The Sierra Club’s Jacob Klein echoed this, saying, “We are learning more and more about the toxic impacts of particulate matter and the environmental racism associated with these emissions.”
However, the .20 limit also had substantial support. A consultant’s report on socioeconomic impacts, prepared as part of the agency’s staff report, concluded that the costs of the .10 limit might result in either employee cutbacks or an increase in gasoline prices, or both. Closures were seen as unlikely, and some public comments suggested that market factors would be the determinant in any decision to shutter a facility. However, refinery workers and their unions agreed with refinery concerns about impacts. Chad Fugate, a third-generation steamfitter, wrote, “We need these refineries to stay open and not run out of town”, while David Akeson was worried that refinery staffing decisions would affect safety, writing, “The recent Chevron fire is still fresh in my mind which was the result of repeat deferral on maintenance due to cost saving.”
District board members were also quite concerned about additional water that would be used in wet gas scrubbers, although reclaimed water and better technology could reduce that impact. Ultimately, they determined that the refinery costs and water usage were substantial unmitigated impacts that were necessary to achieve the benefits of the revised regulation.
Not surprisingly, considering the objections, the Air District has been sued by the two active refineries which will need to upgrade, PBF and Chevron. PBF is already implementing different particulate reduction measures, and maintains that it can’t afford to comply so will shut down. Chevron contests the Air District’s cost-benefit calculations. Both are asking that the rule be set aside; a decision will take several years. Nevertheless, Valero’s improved technology and the switch to refining renewable fuels at Phillips 66, and potentially at Marathon, may indicate the ultimate direction for Bay Area refineries.