Evacuation orders covered parts of six cities after officials warned a failing tank could spill or explode.
GARDEN GROVE, CA — Emergency crews worked Saturday to control a leaking chemical tank at an aerospace plant after evacuation orders sent about 40,000 Orange County residents from homes in and around Garden Grove.
The response centered on a storage tank at GKN Aerospace containing methyl methacrylate, a flammable chemical used in plastics and manufacturing. Fire officials said the tank had overheated, vented vapors and posed two major risks: a ground spill of thousands of gallons or an explosion that could affect nearby tanks. No deaths or injuries had been reported as crews kept working to cool and stabilize the site.
The emergency began Wednesday evening when the Orange County Fire Authority responded to an industrial chemical leak near 12122 Western Ave. in Garden Grove. Initial evacuation orders were lifted that night for residential areas, but officials later said a damaged valve created new problems during the removal process. Evacuation orders were reissued Friday morning and expanded by 1 p.m. as conditions changed. Orange County Fire Authority Division Chief Craig Covey said the tank remained unstable. “This thing is going to fail, and we don’t know when,” Covey said.
The expanded evacuation zone stretched south of Ball Road, east of Valley View Street, west of Dale Street and north of Trask Avenue. The area included parts of Garden Grove, Cypress, Stanton, Anaheim, Buena Park and Westminster. Officials said the tank held about 6,000 to 7,000 gallons of methyl methacrylate. Fire crews used water from a remote setup to keep responders farther from the danger area while lowering the tank’s temperature. Covey said crews had gained time but had not ended the threat. Officials also built sandbag barriers to keep a possible spill from reaching storm drains, creeks or the ocean.
Health officials said the chemical could release harmful vapor if it heats up or escapes. Orange County Health Officer Dr. Regina Chinsio-Kwong said exposure could cause breathing problems, burning or itchy eyes, nausea and headaches. Air monitors had not detected vapor in the evacuation area, officials said Friday, but the risk of a sudden release drove the large evacuation. The city posted emergency updates in English, Spanish, Vietnamese and Korean, reflecting the language needs of a community with a large Vietnamese population. Officials said some residents had refused to leave despite door-to-door warnings.
GKN Aerospace said specialized hazardous materials teams were assessing the incident. The company said its priority was the safety of employees, responders and the surrounding community. Fire officials said local, regional and national experts were being consulted to find a way to depressurize or otherwise secure the tank. Officials said one damaged tank had been neutralized earlier, but the remaining tank became the main concern after crews learned more about its condition. Disneyland’s theme parks, located nearby in Anaheim, were not inside the evacuation area.
Shelters opened for displaced residents as the response stretched into the night. The city said the Red Cross opened an overnight shelter at Freedom Hall, 16801 Euclid St. in Fountain Valley, where pets were allowed. Savanna High School in Anaheim also was listed as an overnight shelter. Earlier evacuation sites included the Garden Grove Sports and Recreation Center and Stanton City Hall. City officials said the Garden Grove Park evacuation center would not provide overnight shelter. Road closures remained near Western Avenue and surrounding streets as crews worked around the plant.
Residents described rushed departures and uncertainty over when they could return. Danny Pham, who lives near the plant, said he left after his roommate woke him and told him to evacuate. He grabbed only basic documents before leaving the area. Kim Yen, a longtime Garden Grove resident, said she received a phone alert Thursday night and worried some neighbors might not understand emergency messages in English. Garden Grove Mayor Stephanie Klopfenstein said officials understood the fear but said the orders were issued because of the danger.
The evacuation orders remained active Saturday as crews continued mitigation work and officials monitored the tank. Authorities had not announced a timetable for reopening neighborhoods or lifting road closures.
Author note: Last updated May 23, 2026.