Container with 26,500 liters of methyl methacrylate overheated in Garden Grove and led authorities to isolate the area
An industrial tank with 26,500 liters of MMA (methyl methacrylate) overheated in Garden Grove and led authorities in Orange County, California (USA), to order the evacuation of more than 40,000 residents on Friday (May 22, 2026), according to .
The case mobilized emergency teams to prevent a possible explosion or leak of the toxic substance. An area of 23 square kilometers was cordoned off around the industrial facilities.
Overheating automatically activated the relief valve and sprinklers to try to cool the container. During containment attempts, teams identified damage to the tank valve, which prevented the chemical from being removed. According to authorities, MMA is highly flammable, toxic and used in the manufacture of plastics.
Evacuation orders were suspended after conditions temporarily improved. However, they were resumed after teams found the mechanical problem in the tank worsening. Around 6,000 residents refused to leave the region, according to local authorities.
Craig Covey, unified commander of the emergency operation, said there are two possible scenarios: the tank could rupture and release its chemical contents or it could explode. “This product is highly volatile, highly toxic and highly flammable”he said. He also stated that the direction of the wind can increase the risks to the population in the event of a leak.
Thirteen schools and two local school district facilities were evacuated. The industrial complex is approximately eight kilometers from Disneyland Resort and about 6 kilometers from Knott’s Berry Farm park. According to health authorities, exposure to MMA can cause severe irritation to the respiratory tract, nausea and dizziness.
The teams continue to monitor the tank continuously. So far, there is no projection on when the container could rupture or on the potential reach of toxic vapors in the event of an explosion.
