Mass Evacuations After Garden Grove Leak

Orange County fire officials ordered mass evacuations in and around Garden Grove after a damaged chemical tank at GKN Aerospace began overheating and leaking methyl methacrylate, a volatile and highly flammable liquid. The incident began on May 21, according to California Governor Gavin Newsom’s emergency proclamation, and escalated on May 22 as authorities said the tank could rupture or explode. Evacuation orders covered parts of Garden Grove and nearby Orange County cities, with officials putting the number of affected residents at roughly 40,000 and later closer to 50,000. Fire crews kept spraying water on the tank while warning residents to stay out of the area. ### How did a leak at one plant turn into a regional evacuation? GKN Aerospace’s facility in Garden Grove became the center of the emergency after a 34,000-gallon tank containing methyl methacrylate developed a leak and began heating up, according to the Orange County Fire Authority. Officials said the tank held about 5,000 to 7,000 gallons of the chemical at the time of the incident. By Friday, authorities said the vessel could no longer be secured safely. (gov.ca.gov) Craig Covey, an Orange County Fire Authority division chief and incident commander, said Friday that responders were preparing for two outcomes: a spill into the surrounding area or a thermal runaway event that could trigger an explosion. Covey said a rupture could release 6,000 to 7,000 gallons of what he called “very bad chemicals” into the parking lot and nearby area. (abcnews.com) ### Which places were told to leave? Garden Grove officials directed residents to the city’s emergency page for evacuation maps, shelter information and road closures. News reports and official updates said the evacuation footprint extended beyond Garden Grove into parts of Westminster, Stanton and Anaheim, with some reports also listing portions of Buena Park and Cypress as conditions changed. Orange County education officials said several school districts and campuses were affected, and more than a dozen schools temporarily closed. (abcnews.com) The Orange County Department of Education said uncertainty remained over whether impacted campuses would reopen after the Memorial Day holiday. ### Why were firefighters still cooling the tank if the leak had already been found? (ggcity.org) Orange County Fire Authority officials said external cooling was meant to slow the heating inside the compromised tank and buy time for specialists to find another way to stabilize it. Early drone readings suggested temperatures were falling, but crews who re-entered the site later found the internal temperature had risen from 77 degrees to 90 degrees. Covey said Saturday that the increase was about one degree per hour. (abcnews.com) The City of Garden Grove told residents to avoid the area and follow official instructions while emergency crews worked. NBC Los Angeles reported Saturday night that the South Coast Air Quality Management District and the U.S. Environmental Protection Agency had reported normal pollutant levels around the evacuation zone, even as the tank remained unstable. ### What is methyl methacrylate, and what were officials worried about? (newsroom.ocde.us) Methyl methacrylate is a flammable industrial chemical used in plastics manufacturing and at aerospace facilities, according to fire officials and multiple news reports. Authorities focused on two risks: a direct chemical release and a blast that could damage nearby tanks containing other fuels or chemicals. That combination is what pushed emergency managers to clear a broad area rather than wait for the tank to fail. (ggcity.org) Gov. Gavin Newsom said on May 23 that California was mobilizing state resources to support local responders and expand shelter capacity. His emergency proclamation said the scale of the incident was beyond the capacity of any single local government and that significant risk of a catastrophic hazardous release remained. (abcnews.com) ### What happens next for residents and officials? May 23 updates from the Orange County Department of Education and the governor’s office said crews were still searching for a way to prevent either a rupture or an explosion. Covey said officials were consulting hazardous-materials specialists and outside experts from across the country while maintaining contingency plans for spill containment. Residents were told to monitor the City of Garden Grove emergency page and Orange County Fire Authority updates for any change in evacuation orders, shelters or school reopening plans. (gov.ca.gov) (newsroom.ocde.us)