About 50 gallons of water spilled into a storm drain at GKN Aerospace in Garden Grove, and Orange County health officials are testing it for any trace of methyl methacrylate (MMA). The spill occurred during routine stormwater transfer, days after a late-May ch
For the third week, the GKN Aerospace site in Garden Grove has been treated like a place that can’t be ignored—even after the big emergency eased.
About 50 gallons of water spilled into a storm drain at the company’s property, Orange County health officials said Friday, and testing is underway to determine whether the water contained any toxic chemicals. The specific focus is whether there are traces of methyl methacrylate, or MMA.
Officials said the spill involved stormwater tied to an area unrelated to the incident site. The Orange County Health Care Agency described it as “an onsite stormwater/condensation tank located in an area unrelated to the incident site.” The agency said the water entered the storm drain during routine handling: as the stormwater was being transferred into a 275-gallon tote for storage and analysis before disposal—“as is typical”—an overflow occurred and approximately 50 gallons of water flowed into the storm drain. The agency said appropriate state and local notifications were made, and a quantity of the spill was collected during cleanup.
Orange County health officials said they believe “the potential for any trace amounts of MMA to be found in the stormwater is low.”
But questions remain about how clean separation really is on the ground. The Health Care Agency did not immediately answer questions Friday about whether some of the water in the stormwater tank may have been sprayed on the crippled tank during the incident response over Memorial Day weekend. During that earlier emergency. officials and experts said sprinklers were vital to help cool a tank that was heating up. reducing the risk of an explosion.
The broader context matters. In late May. a tank holding approximately 7. 000 gallons of MMA at the same facility went into crisis. creating an explosion risk strong enough to force the evacuation of 50. 000 people in portions of Garden Grove. Stanton. Anaheim. Buena Park. Cypress and Westminster. The threat subsided on May 26 after officials confirmed the tank had cracked and was no longer pressurized.
Even as the community moved on from the worst moments, the cleanup and next steps continued. Health officials said a planned move of neutralized MMA from GKN Aerospace’s storage tanks did not happen on Thursday and Friday and will be rescheduled.
During the original emergency. officials had also warned that when neutralized MMA is transferred into sealed trucks for transport and disposal. people might smell a “fruity or plastic-like odor.” Health officials said the product has a “very low odor threshold. ” meaning residents might notice a scent even when concentrations are well below levels associated with health concerns.
The crisis itself began May 21. when the Orange County Fire Authority responded to the crippled pressurized tank that was heating up. A report issued by state officials said the tank released fumes for about five minutes. and air sensors to detect MMA in the area were set up the next day. Those sensors have not detected MMA in the air.
Based on available data, the California Department of Public Health said there is “no risk to the public from MMA exposure from this incident,” and that “No long-term health effects are anticipated in the community as a result of this incident.”
In the days since. the story has turned from the risk of a sudden blast to the slower work of proof: this time. whether a routine stormwater overflow carries anything from a site still associated with MMA. Health officials are now collecting and testing the spilled water. working to determine if the community’s worst fears were echoed anywhere else in the aftermath.
GKN Aerospace Garden Grove methyl methacrylate MMA storm drain spill Orange County Health Care Agency chemical crisis evacuation tank crack