Officials race to cool down tank containing toxic chemical as 50,000 residents remain under evacuation order in Californ

Source: CNN US

Updated May 23, 2026, 5:17 PM ET
PUBLISHED May 22, 2026, 8:21 PM ET


Emergency crews are working nonstop to prevent an overheating tank filled with a toxic chemical from leaking or triggering what could be a catastrophic explosion as approximately 50,000 residents in Orange County, California remain under an evacuation order.

Earlier, the Orange County Fire Authority told CNN 79,000 residents were impacted.

Authorities have spent the past two days trying to prevent the tank, which is full of the chemical methyl methacrylate, from exploding after it began to overheat. Evacuation orders were initially issued to those in the 9-square-mile area around the aerospace facility involved, but the evacuation zone was expanded after experts evaluated the volatile situation.

The chemical, also known as MMA, is used to manufacture plastics and can potentially cause respiratory issues if humans are exposed, according to the Environmental Protection Agency. California Gov. Gavin Newsom declared a state of emergency in Orange County on Saturday as the state ramps up its response to the hazardous chemical incident, including expanding shelter availability for evacuated residents.

Read more: https://www.cnn.com/2026/05/22/us/chemical-spill-orange-county-california