Oil giant Marathon Petroleum is fighting an expanded class-action lawsuit fueled by an investigation by the Guardian and Forensic Architecture, which examined a huge toxic blaze at the company’s sprawling refinery in south-east Louisiana in 2023.
Parts of the oil refinery, the third largest in America, caught fire for over three days in August 2023 after a large storage tank containing the toxic and flammable hydrocarbon naphtha leaked for more than 13 hours unbeknown to the predominantly Black low-income communities that surround the facility.
The incident resulted in one of the largest flammable chemical releases recorded by the Environmental Protection Agency’s risk management program, which monitors accidents at thousands of facilities across the country that store extremely hazardous materials.
The company assured residents living in the heart of the so-called “Cancer Alley” region that “no offsite impacts” had been detected throughout the episode and told government regulators that air monitoring had indicated no harmful level of pollutants in the air beyond the facility’s fenceline. Local officials conducted a brief mandatory evacuation for about 3,000 people living within two miles of the site on the fire’s first day.
But a nine-month examination by the Guardian and the multi-disciplinary research group Forensic Architecture raised significant doubts about these claims and uncovered a series of flaws in the local emergency response.
Dozens of community members had sought hospital treatment during the accident and many reported breathing and other respiratory issues, according to records and interviews. A 3D reconstruction of the disaster, using an array of documents including witness photos, police reports, 911 calls and a fluid dynamics analysis, estimated that some residents had been exposed to levels of benzene, a known carcinogen, over 18 times above the the Centers for Disease Control and Prevention’s acute exposure threshold.
A recently filed amended federal complaint in a class-action lawsuit seeking damages against Marathon draws heavily from the Guardian’s reporting and aims to roughly double the class size to about 16,000 residents who were potentially affected by the accident. The complaint was submitted in the eastern district of Louisiana in November 2024.
“Plaintiffs only recently learned that Marathon ‘shrouded in secrecy’ the 25 August 2023, chemical release and fire at the Refinery, as investigative journalists uncovered and reported to the public for the first time … the affirmative steps that Marathon took to ‘minimiz[e] the episode in its reporting to both federal and state governments,’” the complaint states.
“Numerous records disclosed to the public for the first time by investigative journalists and EPA in September 2024 revealed new details about the scale of the Refinery Fire’s impacts and lengths Marathon undertook to downplay those impacts,” later filings claim.
The oil company has sought to throw the updated complaint out of court on procedural grounds, claiming it was filed outside the statute of limitations.
Marathon Petroleum did not respond to multiple requests for comment.
The class-action suit, which seeks in excess of $5m in damages over an array of alleged legal violations, including negligence, trespass and nuisance laws, is also designed to force the company into further transparency over its handling of the accident, said Kerry Miller, a lead attorney for the plaintiffs.
“The real key here is to change some of these practices when [petrochemical facilities in Louisiana] have upsets,” Miller said. “The status quo of saying ‘no impacts beyond the fenceline’ has got to change. And we see this case as one where we can maybe make that change.”
Miller said discovery would focus on internal communications at the refinery throughout the incident, seeking to examine how the plant’s managers interacted with local officials and company health and safety workers.
Marathon only concluded its internal investigation into the accident in October 2024, well over a year after the event occurred. In its final report to Louisiana’s department of environmental quality (LDEQ), the company said the accident was caused by corrosion of a storage tank, accelerated by low pH.
Neither Marathon nor the LDEQ responded to questions by deadline on whether the company had faced any sanctions following the event.
An investigation by the US Environmental Protection Agency into the facility’s recent accident history, sparked after the Guardian raised a number of findings to the agency, remains ongoing.
Additional records newly obtained by the Guardian suggest more dangerous substances were stored in other tanks that caught fire during the accident. A chemical inventory of the facility, disclosed via records request, shows that another tank that caught fire in the accident contained nearly 10,000 barrels of No 6 fuel oil, a sludgy mixture left over from the refining process that includes polycyclic aromatic hydrocarbons, or PAHs.
PAHs are a group of compounds of which many are known to cause cancer at even small quantities, said Kim Terrell, a research scientist and director of community engagement at the Tulane Environmental Law Clinic.
Records indicate that the handheld air monitoring devices used during the fire weren’t capable of detecting PAHs. The same equipment was not sensitive enough to detect harmful levels of other pollutants either, Terrell said.
“It’s like walking outside with your eyes closed and saying: ‘I don’t see a problem,’” she added.
