Orange County Fire Crews Respond to Toxic Chemical Leak at Aerospace Facility

Fire crews responded Thursday afternoon to a hazardous materials incident at a business in the 12000 block of Western Avenue in Garden Grove. Upon arrival, responders identified a leak of methyl methacrylate from a 34,000-gallon tank at a GKN Aerospace facility.

The Orange County Fire Authority hazardous materials team began cooling the tank Thursday, leading to an initial evacuation order that was later lifted. On Friday morning, officials reported that a faulty valve prevented removal and neutralization of the remaining chemical, raising the risk that the tank could fail or explode.

Firefighters reissued and expanded evacuation orders to include portions of Garden Grove, Anaheim, Buena Park, Cypress, Stanton and Westminster. Cooling efforts continued through the weekend. An update Friday night indicated that water sprays had reduced temperatures, but by Saturday morning officials said the cooling measures were proving less effective than initially assessed.

Methyl methacrylate is a volatile liquid used to produce durable, lightweight plastic. Short-term exposure to its vapors can cause lung and nasal irritation, nausea and dizziness, while higher concentrations may lead to severe respiratory distress. An assistant professor of chemistry at USC stated that keeping the tank cool remains the primary strategy to delay a potential release or explosion.

The polymer form of the material is not considered toxic once cured.