Tens of thousands of residents in Southern California were ordered to evacuate Friday after officials warned that a chemical tank at an aerospace facility is in a critical state and could either rupture or explode.
Crews first responded Thursday to vapor being released from a 34,000-gallon tank at the GKN Aerospace plant in Garden Grove, about 30 miles south of Los Angeles, the Orange County Fire Authority said. The tank holds methyl methacrylate, a chemical used in plastics manufacturing.
By Friday, authorities described the situation as worsening. Although there was no active plume at that time, the tank was described as actively in crisis and could not be secured, prompting expanded evacuation orders.
Orange County Fire Authority Division Chief Craig Covey said there were effectively two possible outcomes: the tank could fail and spill an estimated 6,000 to 7,000 gallons of hazardous material into the facility parking lot, or it could enter a thermal runaway and explode, potentially damaging nearby tanks that contain fuel or other chemicals. Evacuations were ordered to prepare for either scenario.
About 40,000 people were affected by the evacuation orders. More than a dozen schools in the area temporarily closed, and nearby campuses cancelled outdoor activities as a precaution. An earlier evacuation order issued Thursday had been lifted when vapor readings improved, but officials reissued and expanded orders on Friday in response to the renewed threat.
Emergency teams have been working to cool the damaged tank by directing a continuous curtain of water at it. Covey said lowering the tank temperature has bought responders time to explore options for stabilizing the situation, and crews worked through the night seeking a long-term fix. He stressed that simply waiting for a failure was unacceptable.
Officials cautioned that it is unclear when residents will be allowed to return to their homes. The California Governor’s Office of Emergency Services said it was closely monitoring the incident and had deployed personnel to work with local partners. Governor Gavin Newsom had been briefed.
Methyl methacrylate is mainly a respiratory irritant and is commonly used in industrial applications for plastics. Authorities estimated roughly 7,000 gallons remained in the tank. Short-term exposure can cause skin and eye irritation and breathing difficulties, according to the EPA.
Orange County Health Officer Regina Chinsio-Kwong warned that an explosion could aerosolize the chemical, and inhalation of the vapor could lead to severe respiratory problems. Reported symptoms from exposure include sore throat, runny nose, itchy or burning eyes, nausea and headache.
GKN Aerospace, which manufactures aircraft engines and landing gear components for commercial and military customers, was contacted for comment. Local officials urged everyone to follow evacuation instructions and other guidance from emergency responders until the situation is resolved.