State of Emergency declared as Garden Grove chemical tank heats up, California
California Governor Gavin Newsom declared a State of Emergency for Orange County on May 23, 2026, after the state said a methyl methacrylate storage tank at GKN Aerospace in Garden Grove began heating up and emitting toxic fumes, leaving about 50 000 residents subject to evacuation orders.
Satellite view of the GKN Aerospace facility area in Garden Grove, California, where a methyl methacrylate leak from a storage tank was reported at around on May 21, 2026. Credit: The Watchers, ESRI
The proclamation said the tank contained approximately 18 900–26 500 L (5 000–7 000 gallons) of methyl methacrylate, a volatile and highly flammable liquid. It said the incident began on May 21 at the GKN Aerospace facility and that a significant risk remained of a catastrophic event that could lead to a hazardous chemical release.
Newsom’s order directs the California Governor’s Office of Emergency Services and state agencies to support Orange County and affected local jurisdictions. The proclamation also unlocks emergency response authorities, allows state agencies to use personnel, equipment, and facilities for response operations, and makes suitable fairgrounds and state-owned properties available for temporary shelter if needed.
As of 15:12 UTC on May 24, Garden Grove’s emergency page confirmed evacuation orders as active for the GKN Aerospace / MMA Leak at 12122 Western Ave. The evacuation zone was placed south of Ball Road, east of Valley View Street, west of Dale Street, and north of Trask Avenue.
The city first reported the industrial chemical leak at 18:37 LT on May 21, after the Orange County Fire Authority issued an evacuation order for an area north of Garden Grove Boulevard, south of Orangewood Avenue, east of Monarch Avenue, and west of Beach Boulevard.
Residential evacuation orders were lifted at 20:01 LT that evening, but reissued at 09:00 LT on May 22 after damage to a valve on the tank created additional operational challenges and prevented complete mitigation.
At 13:00 LT on May 22, Garden Grove expanded the mandatory evacuation area to Valley View Street, Ball Road, Trask Avenue, and Dale Street, citing changing conditions while mitigation operations continued.
The city said facility and industrial crews were continuing containment and removal work, with support from the Orange County Fire Authority (OCFA), Garden Grove Police, the Orange County Sheriff’s Department in Stanton, and the Orange County Health Care Agency.
GKN Aerospace / MMA Leak — 12122 Western Ave, Garden Grove. Credit: City of Garden Grove. Valid: May 24, 2026
The state declaration followed new operational concerns about the tank’s internal temperature. Reuters reported that crews initially believed exterior cooling was stabilizing the tank, but checks later showed the internal temperature had reached 32°C (90°F), up from 25°C (77°F), with the temperature increasing by about 0.6°C (1°F) per hour.
Fire officials warned that the tank could rupture and spill up to 26 500 L (7 000 gallons) of methyl methacrylate or explode and endanger nearby tanks. This made crews shift from a defensive stance to an offensive operation with help from chemists from the manufacturer’s emergency response team. Procedures were also in progress to neutralize a nearby 56 800 L (15 000-gallon) tank to reduce its explosive potential if the smaller tank failed.
Officials said firefighters continued spraying the outside of the tank with water to cool the chemical and prevent an explosion. Valves on the tank are reportedly broken or gummed up, preventing crews from removing the chemical or relieving pressure, while drones monitored temperatures at 10-minute intervals.
No injuries had been reported, and air monitoring around the evacuation zone remains within normal limits. Crews also set up containment barriers to keep any release from reaching storm drains, creeks, or the nearby ocean.
Methyl methacrylate is used in plastics and manufacturing. Exposure can cause serious respiratory problems, neurological effects, and irritation of the skin, eyes, and throat. Orange County Health Care Agency officials said residents were safe outside the evacuation zone established by authorities.
References:
1 Proclamation of a State of Emergency – State of California – May 23, 2026
2 Governor Newsom proclaims state of emergency in Orange County in response to ongoing chemical incident in Garden Grove, makes additional shelter sites available – State of California – May 23, 2026
I'm a dedicated researcher, journalist, and editor at The Watchers. With over 20 years of experience in the media industry, I specialize in hard science news, focusing on extreme weather, seismic and volcanic activity, space weather, and astronomy, including near-Earth objects and planetary defense strategies. You can reach me at teo /at/ watchers.news.
Commenting rules and guidelines
We value the thoughts and opinions of our readers and welcome healthy discussions on our website. In order to maintain a respectful and positive community, we ask that all commenters follow these rules.