What to KnowAbout 50,000 residents in Garden Grove and Stanton were evacuated during Memorial Day weekend as authorities worked to neutralize the toxic chemical inside a tank at GKN Aerospace. Ultimately, a crack in the damaged tank relieved pressure, allowing authorities to give the all-clear for residents to return home days after the crisis began.The prosecutors office announced that it has reached a $125 million settlement agreement with civil case defendants GKN Aerospace Transparency Systems, Inc. and GKN Aerospace, Inc. The civil case agreement must still be reviewed and approved by a judge before finalized.The agreement includes a claims program of up to $100 million for residents who evacuated the surrounding area for days.
The Orange County prosecutors office announced that it has reached a $125 million settlement agreement with the aerospace company at the center of a toxic chemical tank emergency in May that forced 50,000 residents to evacuate in the Garden Grove area.
The civil case agreement between the Orange County District Attorney’s Office and defendants GKN Aerospace Transparency Systems, Inc. and GKN Aerospace, Inc. must still be reviewed and approved by a judge before finalized.
The agreement includes a claims program of up to $100 million for residents who evacuated the surrounding area for days, including Memorial Day weekend, due to the threat of an explosion and toxic plume. Resident and businesses whoa re eligible can be reimbursed for expenses like hotel stays, loss of use, and per diem compensation for meals, transportation, and loss of wages
About 13,000 to 17,000 households were evacuated during a five-day period beginning May 21. They included properties within a potential blast radius map released to the public that showed which areas would be affected by an explosion and resulting toxic chemical plume.
In a statement Monday, the company said it has completed work to begin the claims program, which it said would start within days of the judge’s approval. The company scheduled a meeting for Oct. 27 to provide more information about the program.
“As GKN previously announced, we have been working diligently to resolve the Orange County District Attorney’s Office’s civil investigation regarding the May incident,” GKN said in its statement. “Today, the DA’s Office filed in court the necessary documents to initiate the process of resolving the investigation. The proposed resolution includes a claims program of up to $100 million for affected residents and businesses and a safety plan.
“GKN has completed the preparatory work necessary to launch the claims program. Contingent upon Court approval, GKN would open the claims program within days. Under the proposed program, online and in-person support would be available in English, Spanish, Vietnamese, and Korean. We will also hold a community event on October 27, at which the community will have an opportunity to interact with GKN and learn more about the claims program. Further details will be announced in the days leading up to the event.”
The settlement includes more than $8.4 million for emergency response and abatement costs.
The agreement requires a safety and monitoring plan with an outside expert provided oversight of GKN operations for at least the next seven years. None of the requirements will go into effect until the agreement is approved by a judge.
Several days of uncertainty began with reports of overheating and pressure building in one of the toxic chemical storage tanks. Firefighters said it appeared the tank would either explode or spill its toxic contents after a problem with the valve used to release pressure.
Ultimately, a crack in the damaged tank relieved pressure, allowing authorities to give the all-clear for residents to return home days later.
About 14,000 gallons of the chemical was removed at GKN Aerospace, according to officials. Hetty Chang reports for the NBC4 News at 5 p.m. on Monday, June 29, 2026.
In late June, hazardous materials teams began removing thousands of gallons of methyl methacrylate (MMA) from storage tanks.
Earlier in June, Orange County approved an allocation of $500,000 to help reimburse residents who were impacted by the evacuation order.
The company, which manufacturers parts for military aircraft, began operations in 1966 and employs about 500 local residents.