Southern California Chemical Tank Prompts Evacuations Near Garden Grove

More than 40,000 residents in parts of Garden Grove and nearby cities were ordered to evacuate Friday after officials warned that a chemical storage tank at an aerospace facility could fail or explode. The tank holds an estimated 7,000 gallons of methyl methacrylate, a flammable substance used in plastics manufacturing.

Officials said the chemical can generate its own heat and that any leak could lead to fire or explosion if exposed to a spark.

The situation developed Thursday when workers noticed the tank was unstable. By Friday the tank was visibly bulging, prompting fire crews to begin cooling it from a safe distance with mechanical equipment. Officials described two possible outcomes: the tank could crack and release its contents into a parking lot, or it could explode and affect surrounding tanks.

Containment barriers made of sandbags were placed to keep any spill out of storm drains. >"I know I keep talking about we were handed this situation where there’s only two things that can happen: it could crack and leak, or it could blow up. Air-quality monitors had not detected any chemical vapor as of Friday, though residents outside the evacuation zone reported smelling a sharp, fruity odor.

Health officials said prolonged exposure to the vapor could cause respiratory irritation. People inside the one-mile evacuation radius were told to leave; those outside the zone were advised to stay indoors. " Schools and roads in the affected areas were closed.

Three evacuation shelters were opened in Garden Grove, Anaheim, and Cypress. Police said about 15 percent of residents under evacuation orders had not yet left their homes. The cause of the tank’s condition remains under investigation. Officials said they are consulting with experts across the state and country to determine next steps.