40,000 people evacuated in California as firefighters race to prevent toxic chemical tank from exploding

world | ABC News Australia | 2026-05-25T19:19:00.000Z

About 40,000 people have been evacuated from an area near Los Angeles after a tank containing 26,000 litres of methyl methacrylate, a highly toxic and flammable chemical, began overheating. Fire officials are racing to prevent a catastrophic explosion after damaged valves prevented the reaction from being neutralised. A crack in the tank may be reducing the worst-case scenario risk.

About 40,000 people have been evacuated from areas around Golden Grove, approximately 48 kilometres south of Los Angeles, after a tank containing up to 26,000 litres of methyl methacrylate began overheating at an aerospace facility. Methyl methacrylate is a highly toxic and flammable chemical used in the manufacture of plastics, and authorities warned the tank could either rupture and spill its contents or violently explode and potentially affect other tanks on the site.

The crisis began on Thursday when the tank started overheating. Damaged valves on the tank meant the dangerous chemical reaction could not be neutralised through normal safety procedures, leaving firefighters to work around the clock to try to keep the chemical cool and prevent a catastrophic failure. The situation has forced tens of thousands of residents into temporary shelters nearby.

In a cautiously optimistic development, fire officials announced they believe they have discovered a crack in the tank that could be reducing the chance of the worst-case explosion scenario. A senior fire official described the latest operation as giving positive intelligence to make educated decisions, calling it a step in the right direction while cautioning that the danger has not yet passed.

Evacuees have been spending the weekend in nearby temporary shelters with no clear timeline for when they might be allowed to return. Residents expressed deep anxiety about the unknown. One displaced person said they feel really stressed because they are not sure what the future holds, whether chemicals already in the air might affect them, or what would happen if the tank does explode.

The incident has raised questions about the storage and monitoring of hazardous chemicals in populated areas near Los Angeles. It remains unclear how long it will take for the evacuation zone to be deemed safe for residents to return, with officials continuing to monitor the tank's condition and working to develop a plan for permanent neutralisation of the chemical threat.