50,000 under evacuation orders after chemical tank overheating

More than 50,000 residents in Southern California remained under evacuation orders Monday after a damaged chemical storage tank at an aerospace facility began overheating and venting vapors, creating the risk of a major leak or explosion. The tank, located at GKN Aerospace Transparency Systems in Garden Grove, about 40 miles south of downtown Los Angeles, holds between 6,000 and 7,000 gallons of methyl methacrylate, a volatile and flammable liquid used to manufacture plastic parts for commercial and military aircraft.

Firefighters responded Thursday afternoon to reports of the chemical release. Initial evacuation orders were lifted that night after crews appeared to make progress cooling the tank with water, but the condition deteriorated by early Friday, prompting authorities to reinstate and expand the evacuation zone. Officials later discovered that a valve on the tank had frozen, preventing them from safely offloading the chemical or adding a stabilizer. The evacuation zone now covers parts of Garden Grove, Stanton, and Cypress, stretching from Ball Road to Trask Avenue and from Valley View Street to Dale Street.

Orange County Fire Authority Division Chief Craig Covey said...