The train had departed Madison, Illinois on February 1, bound for Conway Yard in Pennsylvania on the Fort Wayne Line. Aboard were an engineer, conductor, and conductor trainee, hauling roughly 18,000 tons across 150 cars. Twenty of those cars carried hazardous materials. When the 38 cars derailed on the east side of town, fires erupted immediately and burned for more than two days. Nearly 70 emergency agencies from Ohio, West Virginia, and Pennsylvania mobilized. East Palestine Mayor Trent Conaway declared a state of emergency. On February 5, a temperature spike in one of the tank cars raised fears of an explosion that could disperse shrapnel across the area. Five cars of vinyl chloride remained intact, but a relief valve on one had malfunctioned. Ohio Governor Mike DeWine called it "a matter of life and death" and activated the National Guard.

On February 6, authorities ordered a mandatory evacuation and then conducted a controlled release and burn of five tank cars of vinyl chloride. Shaped charges breached the tanks, the chemical flowed into a trench, and flares ignited it. Black clouds billowed over the region, releasing phosgene and hydrogen chloride into the air. Residents across Mahoning and Trumbull counties reported a chemical smell; officials in the Youngstown region advised people to stay indoors. A year later, NTSB Chair Jennifer Homendy testified before the U.S. Senate that the burn was unnecessary. The temperature in the derailed tank cars had been descending, and no deadly chemical reaction was occurring. OxyVinyls, which manufactured the vinyl chloride, did not believe polymerization was imminent. Ohio Senator Sherrod Brown said the burn proved Norfolk Southern valued profit over safety. Senator JD Vance suggested the company rushed the burn to reopen the rail line and move freight.

The chemical spill killed more than 43,000 fish, crustaceans, amphibians, and other aquatic animals across multiple waterways. Contaminants were detected in Sulphur Run, Leslie Run, Bull Creek, the Little Beaver Creek system, and the Ohio River. Residents reported pets dying overnight during the controlled burn. Seven CDC investigators who inspected the site in early March fell sick with symptoms matching those of local residents. A June 2024 analysis of rain and snow samples by the National Atmospheric Deposition Program found extreme concentrations of pollutants and exceptionally high pH levels across an area spanning portions of sixteen U.S. states. Independent testing by Carnegie Mellon University and Texas A&M detected chemicals in the air above long-term exposure limits, including vinyl chloride, benzene, and acrolein. An EPA whistleblower alleged the agency delayed deploying chemical-sensing aircraft and turned off sensors -- claims the EPA denies.

The legal and financial reckoning was enormous. By early 2025, Norfolk Southern had committed over $115 million to East Palestine, removed more than 167,000 tons of contaminated soil and over 39 million gallons of tainted water. The railroad agreed to a $600 million class-action settlement and a separate $310 million federal consent decree covering cleanup costs, Clean Water Act penalties, a 20-year community health program, and a decade of water monitoring. Total costs exceeded $1.1 billion. The NTSB determined that an overheated wheel bearing caused the derailment, and its board unanimously declared Norfolk Southern's chemical burn "misguided." NTSB Chair Homendy accused the company of threatening the board, attempting to manufacture evidence, and withholding documents -- calling the behavior "unconscionable" and "reprehensible." Testimony revealed that since 2019, Norfolk Southern had slashed expert car inspectors and substituted abbreviated 12-point crew inspections for the standard 90 to 105-point expert checks.

Two years after the derailment, Norfolk Southern trains carrying hazardous materials -- including vinyl chloride and butyl acrylate -- still pass through East Palestine at least ten times a day. The company has hired 1,600 new employees, installed additional hot-box detectors on each side of town, and achieved a 40 percent decrease in mainline derailments in 2023. But the community's trust remains fractured. A February 2025 lawsuit alleged that at least seven people, including a one-week-old infant, died as a result of the toxic chemical leak. Families have described the relocation assistance process as exhausting and arbitrary. The story of East Palestine sits in a longer lineage of industrial pollution crises in the Ohio River valley, stretching back to the Donora Smog of 1948. Erin Brockovich, who arrived within weeks of the derailment, framed the disaster bluntly: decades of deferred infrastructure, weakened regulations, and profits prioritized over people had made something like this inevitable.