Firefighters in Orange County, California are working around the clock to cool a 7,000-gallon tank containing a volatile chemical that officials say is on the verge of exploding at a Garden Grove aerospace facility. Governor Gavin Newsom declared a state of emergency on Saturday as approximately 40,000 residents across multiple cities remain under evacuation orders in what authorities warn could become one of the worst chemical incidents in California history.
The hazardous materials event began Thursday with a vapor release at GKN Aerospace in Garden Grove, located about 35 miles southeast of downtown Los Angeles. Emergency crews have been battling to stabilize the situation ever since, using sprinklers and hose lines to cool the facility and prevent a catastrophic explosion.
Main Developments
The primary concern centers on a 7,000-gallon tank filled with methyl methacrylate, a highly flammable chemical. The tank temperature has climbed into the 90 to 100 degrees Fahrenheit range, which officials describe as volatile. On Saturday afternoon, the temperature was rising at an average rate of 1 degree per hour.
Chief Craig Covey of the Orange County Fire Authority, serving as incident commander, emphasized the severity of the threat during a news conference. “We’re talking about possibly one of the worst chemical incidents in California history,” Covey said. “We are literally on the edge of it.”
The situation at the GKN Aerospace facility involves not just one tank but potentially three. In addition to the 7,000-gallon tank at immediate risk, a 15,000-gallon tank nearby holds the same substance, and a third 4,500-gallon tank is also on site. A worst-case scenario could involve explosions affecting all three tanks, totaling 26,500 gallons of the toxic chemical.
“We’re doing everything we can to find ways to mitigate that. The worst-case scenario is that fireball,” Covey stated.
What We Know So Far
The hazmat event started Thursday when a vapor release occurred at the facility. Evacuation orders began Friday as the situation escalated. Governor Newsom declared a state of emergency in Orange County on Saturday, mobilizing additional state resources to address the crisis.
During an overnight inspection operation on Saturday, firefighters discovered something that may offer hope. They identified a potential crack in the tank that could be relieving pressure. However, officials stressed that this information is still being validated.
“Last night was a successful operation for this emerging incident and this ongoing incident,” officials said during a briefing. Crews are working Sunday to confirm whether the crack theory is accurate.
The tank walls are constructed of 1-inch-thick steel. Temperature readings have shown a rise from 77 to 90 degrees, placing the chemical in an increasingly dangerous state.
Interim Orange County Chief TJ McGovern and Dr. Regina Chinsio-Kwong, the Orange County health officer, have been involved in coordinating the emergency response. Garden Grove Police Chief Amir El-Farra has assisted with evacuation efforts.
“This is serious. This is real,” officials told residents during public briefings.
What Happens Next
Emergency crews continue their cooling operations at the facility while working to validate information about the potential crack discovered during Saturday night’s inspection. If the crack is confirmed, it could mean that pressure inside the tank is being naturally relieved, potentially reducing the explosion risk.
However, officials have made clear that the danger has not passed. The situation remains fluid, and firefighters are continuing their efforts to prevent a catastrophic outcome.
“We don’t have information of a similar situation where this happened,” officials acknowledged, underscoring the unprecedented nature of the emergency.
Residents should monitor official announcements for updates on when evacuation orders may be lifted or modified.
Important Details
Approximately 40,000 residents are currently under evacuation orders. The evacuations affect multiple cities in the Orange County area, including Garden Grove, Cypress, Stanton, Anaheim, Buena Park, and Westminster.
An emergency evacuation center has been established in Fountain Valley to assist displaced residents. Those who have been evacuated should proceed to this location if they need shelter or assistance.
The state of emergency declaration by Governor Newsom allows for expedited access to state resources and funding to support the emergency response and recovery efforts.
Methyl methacrylate is a flammable chemical commonly used in industrial and manufacturing applications. When heated to volatile temperatures, it poses significant explosion and fire risks.
Frequently Asked Questions
What chemical is in the tank threatening to explode in Garden Grove?
The tank contains methyl methacrylate, a flammable chemical. The primary tank of concern holds 7,000 gallons, with two additional tanks on site containing 15,000 and 4,500 gallons respectively.
How many people have been evacuated due to the Garden Grove chemical emergency?
Approximately 40,000 residents are under evacuation orders. Affected cities include Garden Grove, Cypress, Stanton, Anaheim, Buena Park, and Westminster. An evacuation center has been set up in Fountain Valley.
When did the Garden Grove chemical tank emergency begin?
The hazmat event started Thursday with a vapor release at the GKN Aerospace facility. Evacuation orders began Friday, and Governor Newsom declared a state of emergency on Saturday, May 24, 2026.
What is the worst-case scenario for the Garden Grove chemical incident?
According to incident commander Chief Craig Covey, the worst-case scenario involves a fireball from explosions potentially affecting three tanks on site containing a combined 26,500 gallons of methyl methacrylate.
Where is the Garden Grove chemical emergency evacuation center?
An emergency evacuation center has been established in Fountain Valley for residents displaced by the evacuation orders.
Ongoing Emergency Response
Firefighters remain on scene using sprinklers and hose lines to cool the facilities at GKN Aerospace. The cooling efforts are designed to prevent the tank temperature from climbing further into the volatile range, which could trigger an explosion.
The incident represents an unusual challenge for emergency responders. Officials have acknowledged that they lack precedent for a situation exactly like this one, making the response particularly complex.
Orange County Fire Authority crews conducted an overnight operation Saturday night during which they identified the potential crack in the tank. While this finding could prove to be positive news if confirmed, authorities have cautioned that validation is still needed.
The state of emergency declaration ensures that state agencies can provide support without typical bureaucratic delays. Governor Newsom’s action came as the scope of the potential disaster became clearer over the weekend.
Residents in the affected areas should continue to follow all evacuation orders and monitor official sources for the latest information. Those needing assistance should proceed to the Fountain Valley evacuation center. The situation remains active, and emergency crews continue working to avert what officials have described as a potential historic disaster for the state of California.
