Toxic Leak Turns Into ‘Ticking Time Bomb” As Officials Fear Massive Explosion

A massive chemical leak at an aerospace facility in Garden Grove, California, has sparked fears of a possible explosion after officials warned that a giant chemical tank could become unstable if crews cannot stop the dangerous reaction happening inside.

The incident began Thursday afternoon at the GKN Aerospace facility on Western Avenue, where a 34,000-gallon tank started releasing toxic chemicals into the air, triggering evacuations across parts of west Garden Grove. Authorities say the tank contained methyl methacrylate, commonly known as MMA, a highly flammable chemical used in the production of acrylic plastics and aerospace materials.

Orange County Fire Authority officials quickly evacuated buildings in the surrounding area, stretching from Western Avenue to Beach Boulevard and from Garden Grove Boulevard to Orangewood Avenue. Streets were shut down as hazmat crews rushed to contain the leak while thick fumes poured into the sky.

Officials now say the situation has become even more dangerous because the chemical reaction inside the tank continues to build pressure. According to reports Friday morning, authorities warned there are essentially “two options left” for the tank: “it fails or it blows up” according to ABC7.

WATCH:

“It fails” or “it blows up.”

Evacuation orders were reissued Friday for thousands of residents and schools were closed in Garden Grove due to continued concerns about a toxic chemical leaking from a large storage tank at an aerospace facility.

“There are literally two options… pic.twitter.com/g1sy2jiBZT

— ABC7 Eyewitness News (@ABC7) May 22, 2026

“There are literally two options left remaining: one, the tank fails and spills a total of about six-to-seven thousand gallons of very bad chemicals into the parking lot in that area — or two, the tank goes into a thermal runaway and blows up, affecting the tanks around them that have chemicals in them as well,” OCFA Division Chief Craig Covey said.

The frightening warning has fueled concerns among nearby residents who already spent hours under evacuation orders as toxic vapors drifted through the area. Emergency officials reportedly fear that if the tank ruptures violently, it could spread hazardous material over a much wider radius and potentially ignite.

Aerial footage from local television stations showed the massive storage tank continuously venting chemical vapor while firefighters monitored the scene from a distance. Authorities have not yet confirmed exactly what triggered the dangerous reaction, though reports indicate chemicals may have mixed inside the tank, worsening the situation.

Evacuation orders remain in place:
• North of Garden Grove Blvd
• East of Monarch
• South of Orangewood
• West of Beach Blvd

— OCFA (@OCFireAuthority) May 22, 2026

Some reports suggested nitric acid may have interacted with another chemical compound at the plant, creating an unstable reaction that generated heat and pressure.

Methyl methacrylate presents serious health risks when inhaled. Exposure can cause respiratory irritation, dizziness, headaches, nausea, and breathing difficulty. Because the chemical is also highly combustible, officials have been extremely cautious about allowing anyone near the facility while crews work to stabilize the tank.

Emergency responders established a reunification center at Rancho Alamitos High School while evacuations remained in effect. Authorities later lifted some evacuation orders, though fire officials continued monitoring the site overnight and into Friday due to ongoing concerns about the tank’s stability.

Residents described the scene as surreal, with a strong chemical odor spreading across the neighborhood as emergency vehicles flooded the area. Social media videos showed large plumes rising into the air while helicopters circled overhead documenting the unfolding crisis.

The incident has drawn comparisons to previous industrial chemical disasters where overheating storage tanks created catastrophic explosions. Hazardous materials experts are reportedly weighing whether to let the reaction burn itself out naturally or attempt additional intervention measures that could carry their own risks.