Threat of massive chemical explosion eliminated in Southern California, officials say

Threat of massive chemical explosion eliminated

Orange County Fire authorities said the threat of a chemical explosion has been eliminated. 

GARDEN GROVE, Calif. - Emergency crews continue to work around the clock to prevent a chemical plant in Garden Grove from leaking or exploding, with an estimated 50,000 Orange County residents under evacuation orders. 

What they're saying:

On Monday morning, the Orange County Fire Authority said the threat of a massive explosion had been eliminated. 

"Our concern was that the pressure in the tank was building up to a point that it could potentially BLEVE at any moment. The crews that went in last night discovered that the crack that was on the tank was releasing the pressure, and so now that BLEV potential is completely off the table, which is great news," explained Orange County Fire Authority Capt. Nick Garton. 

"The temperatures as the cruise read last night were at 93 degrees, and they're trending downwards, and we're going to continue monitoring throughout the day," he added. 

In addition, all evacuation orders remain in place. 

" I know everybody's itching to get back home. We have to continue to monitor and make sure that that temperature continues to trend in the right direction as the sun heats up. So we're going to continue monitor that, make sure everything is 100% safe before we release people to get into their homes. But we're gonna do that as soon as possible," Capt. Garton said. 

The backstory:

The incident began on Thursday, May 21 at GKN Aerospace on Western Avenue in Garden Grove.

That's where a 34,000-gallon storage tank containing methyl methacrylate (MMA), a toxic, highly flammable liquid chemical used to manufacture acrylic plastics, began to overheat.

During the earlier stages of the investigation, Orange County Fire Authority (OCFA) Division Chief Craig Covey said a faulty valve on the tank prevented crews from off-loading or introducing a neutralizing stabilizer into the chemical material.

Residents taking legal action

Dig deeper:

Some Garden Grove residents filed a class-action federal lawsuit Saturday against GKN Aerospace Transparency Systems, which operates the facility where the tank is located. Lawyers for the residents argued that regardless of what happens, property values in the surrounding community are sure to be impacted.

GKN Aerospace did not comment on the lawsuit but has apologized to residents and businesses forced to evacuate. It said Sunday it was "working around the clock to mitigate the risk of a leak."

GKN Aerospace agreed in 2025 to pay state regulators more than $900,000 to settle violations involving recordkeeping, permitting issues and nitrogen oxide emissions, according to a report on the South Coast Air Quality Management District website.

Theme parks remain open

Some of Southern California’s biggest theme parks are near the chemical leak and have not been impacted. Knott’s Berry Farm, which is about five miles away, has not been impacted. Disneyland, which is also about 5 miles away, also remains fully operational. A Disney spokesperson confirmed with KTVU's sister station, FOX 11, there was no impact to the park or the resorts. 

Park officials continue to monitor the situation.