An investigation by inewsource found that Montgomery-Gibbs Executive Airport in Kearny Mesa sold more than 1 million gallons of leaded aviation fuel over the past two years, making it the highest lead-polluting general aviation airport in the country, according to federal data obtained through records requests. The investigation also found that flight paths from the three-runway, city-owned airfield pass over or within two miles of more than 30 schools. The fuel it primarily sells is linked to permanent damage to the brain and central nervous system.
The findings come from an investigation by inewsource, which spent months reviewing documents, conducting interviews, filing records requests, and analyzing flight data. The outlet reported that Montgomery-Gibbs sold more leaded fuel in 2025 than in any other year in over a decade, even though the city introduced an unleaded alternative, UL94, at the airport in November 2024. Mayor Todd Gloria celebrated the fuel's arrival, but fixed-base operator Crownair Aviation sold just over 24 gallons of UL94 at Montgomery-Gibbs in the two years since, according to the report.
A Growing Airfield in a Dense Urban Pocket
Local non-military operations at Montgomery-Gibbs have nearly doubled over the last decade compared to the decade before, the investigation found. The airport logged more than 386,000 total flight operations in 2024 alone, according to Hoodline's prior coverage, cementing its role as one of the busiest general aviation airfields in California and a primary FAA-designated reliever for San Diego International. The airport's touch-and-go flight paths pass over parks, playgrounds, and neighborhoods where more than half of residents belong to racial and ethnic minority groups, the report notes.
Leaded aviation fuel accounts for an estimated 70% of lead released into the air nationally, a figure echoed by the U.S. Environmental Protection Agency's October 2023 endangerment finding, which formally determined that lead emissions from piston-engine aircraft endanger public health and welfare. The EPA report assumes 72% of a typical general aviation airport's fleet is piston-powered, but Montgomery-Gibbs' own airport master plan states that more than 93% of its fleet runs on piston engines — far above that national assumption.
What Federal Findings Do—and Don't—Require
The U.S. Environmental Protection Agency says airborne lead levels in the United States have declined 99 percent since 1980, while piston-engine aircraft using leaded fuel remain the largest source of lead emissions into the air. That nationwide trend does not quantify emissions or exposure at Montgomery-Gibbs. The EPA’s endangerment finding established that lead emissions from aircraft engines cause or contribute to air pollution that may endanger public health and welfare, but the agency says the finding did not itself ban or restrict leaded fuel or establish new aircraft-emissions controls, according to the EPA. A separate case involving Santa Clara County’s Reid-Hillview and San Martin airports shows how a local fuel restriction can face federal scrutiny. The FAA ordered the county to submit a corrective action plan addressing its ban on acquiring, storing, and selling 100LL at the two airports, then later granted the county’s request for an extension, according to the Aircraft Owners and Pilots Association.
Lead Emissions at the Airport
The airport emits 1.4 metric tons of lead annually.
Compounding the gap, the San Diego County Blood Lead Prevention Program does not conduct targeted testing of children in communities surrounding Montgomery-Gibbs, even though California state law requires targeted testing for children believed to be at greatest risk of lead poisoning, per the inewsource findings. Researcher Paula Stigler Granados recommended targeted air, soil, and dust monitoring along with blood-lead testing for children in nearby communities, according to the same report.
What the Science Shows Elsewhere
A 2024 Colorado study found that leaded aviation fuel emissions had a small but statistically significant impact on blood lead levels in children living within two miles of an airport. A separate study commissioned by Santa Clara County found that lead levels during peak hours near its Reid-Hillview Airport were half those measured at the height of the Flint water crisis — a comparison that contrasts with earlier peer-reviewed findings published in PNAS Nexus in January 2023, which found blood lead level increases of up to 0.72 µg/dL among children downwind of that same airport, matching or exceeding Flint-era increases. That earlier research, conducted by Dr. Sammy Zahran, prompted Santa Clara County to ban the sale of leaded fuels at Reid-Hillview and San Martin airports in 2022. The Federal Aviation Administration subsequently challenged Santa Clara County's leaded-fuel ban in court. Separately, the City of Torrance banned touch-and-go landings to curb pollution.
A Federal Fix Years in the Making — and Possibly Delayed
The FAA launched a task force back in 2011 to develop a program replacing leaded fuel, and in 2016 then-administrator Michael Huerta said the agency was on track to authorize an unleaded fuel within two years. A decade later, the FAA still says there is no completely compatible, market-ready replacement fuel, even as its EAGLE initiative targets a 2030 phaseout. The FAA has released a plan, though officials have publicly said that timeline may still slip.
Until a fully authorized replacement exists, FAA mandates require federally funded airports to keep leaded fuels available, a federal grant-assurance obligation that constrains what cities like San Diego can do unilaterally. General Aviation Modifications, Inc.'s G100UL was approved for use but was not yet commercially available. The California Air Resources Board recommended this year that the FAA streamline approval of an industry-standard fuel, and Matthew Lakin has urged the agency to establish firmer regulatory requirements.
Why Unleaded Hasn't Caught On Locally
UL94, the unleaded option available at Montgomery-Gibbs, is a lower-octane fuel, and the FAA is working to expand its eligibility. Jorge Rubio attributed the fuel's low sales figures to industry reluctance to adopt a fuel with new safety and performance parameters, per the inewsource report. Crownair Aviation president Ray Richmond said interim UL94 sales may have little impact until a fully compatible, affordable, and accessible alternative becomes available.
California's own deadline looms regardless of federal pace. Governor Gavin Newsom signed the nation's first ban on leaded aviation fuel in September 2024, authored by State Senator Caroline Menjivar, prohibiting sales statewide starting January 1, 2031. The airport expansion plan proposes space for a future fuel tank.
Neighbors Push Back on Noise and Health Risks
Frustration has built for years in the neighborhoods beneath Montgomery-Gibbs' flight paths. Clairemont alone recorded more than 5,000 airport noise complaints between May and August this year, and the advocacy group Quiet Skies MYF now counts more than 100 members, while a Change.org petition has drawn more than 500 signers. San Diego resident Robert Germann has advocated for mandatory unleaded fuel use among airport businesses and flight schools, arguing that aircraft owners should not fly planes that are unsafe on unleaded fuel.
That tension has spilled into local politics. During a San Diego City Council District 2 candidate debate in September, candidate Sarah Crosby proposed closing Montgomery-Gibbs entirely and redeveloping its 456-acre site into housing, citing the same pollution and noise complaints, as Hoodline previously reported. With the airport selling more leaded fuel last year than in any other year in over a decade, and no local air sampling conducted despite meeting federal monitoring thresholds, the question of who is breathing that exhaust — and what, if anything, will be measured — remains unresolved.
