Emergency officials have lifted the evacuation order for many residents living near a hazardous chemical tank at the GKN Aerospace Transparency Systems plant in Garden Grove, Southern California. This decision comes after a significant drop in temperatures inside the tank, which reduced the risk of a catastrophic explosion. Previously, the area had been under evacuation since Thursday due to concerns regarding overheating.
While the immediate threat of a major explosion has been mitigated, officials, including Orange County Fire Authority division chief Craig Covey, warned that there is still a possibility of a smaller explosion or fire. In a news conference on Monday, he stated that an evaluation of the tank containing between 6,000 to 7,000 gallons (22,700 to 26,500 liters) of methyl methacrylate—known for its flammability—showed a decrease in pressure due to a discovered crack. As a result, about two-thirds of the 50,000 residents affected by the evacuation can now return home.
Covey emphasized that while the risk of a large explosion is no longer present, further steps must be taken to address the ongoing concerns about fire and potential spills. He noted that the tank’s interior temperature had cooled to 93 degrees Fahrenheit (33.9 degrees Celsius) from 100 degrees Fahrenheit (37.7 degrees Celsius), demonstrating progress in the handling of the hazardous situation.
Orange County Health Director Regina Chinsio-Kwong reassured returning residents that they could feel safe, emphasizing that there had been no contamination or fumes released during the incident. She clarified that exposure to methyl methacrylate can lead to serious health issues but reported no leakage occurred during the emergency.
However, environmental risks remain, as the remaining methyl methacrylate in the tank is still active and has the potential for an explosion if temperatures do not decrease further. Purdue University engineering professor Andrew Whelton cautioned that a safe handling temperature would require the internal conditions to drop closer to 60 to 70 degrees Fahrenheit (15.6 to 21.1 degrees Celsius). He also explained that the overheating had caused the chemical to change from liquid to gas, increasing pressure and risks of an explosion.
To address the situation, crews have been actively working to cool the tank, including the removal of external insulation material. GKN Aerospace, a British company that produces components for military and commercial aircraft, issued a statement apologizing for the disruption and expressing their priority in resolving the incident safely. The company has a considerable presence, employing around 16,000 people across multiple countries.
Responses from residents reflect a mix of relief and lingering concern. Kim Yen, a retiree living near the plant, expressed happiness upon hearing that the most severe risks had passed but noted that she would wait for verification of safety before returning home. Meanwhile, various facilities and shelters have been accommodating evacuees over the weekend.
Orange County Supervisor Janet Nguyen indicated that the local air quality will be monitored closely, and the EPA will assess local drainage and sewer systems for potential contamination. Public health officials have stated that while the chemical is detectable by smell, it poses no immediate harm to individuals in the area.
Finally, it has been noted that disruptions in this particular manufacturing sector could have a significant impact on the aerospace industry, which operates with tight supply chain margins. Richard Aboulafia, an aerospace consulting expert, highlighted that with low production rates, any halt in supply can be cumbersome for the industry.
