Damaged chemical tank Southern California Fire officials said Sunday there was a crack — which could reduce the risk of a catastrophic explosion — though an evacuation order remains in place for about 50,000 area residents with no timeline on when they can return.
Fire officials were able to closely evaluate the tank overnight and discovered that the tank had cracked, said Captain Weihao Huang of the Orange County Fire Authority.
None of the highly volatile chemicals in the tank appear to have leaked, Huang told The Associated Press earlier Sunday. “There is still a risk of a possible explosion,” Huang said.
Firefighters spray the tank with water in an attempt to cool the chemicals inside and prevent an explosion.
Democratic Gov. Gavin Newsom, who declared a state of emergency on Saturday, said in a post on X that he had asked President Donald Trump to issue an emergency declaration to bolster federal support for local and state officials.
The pressurized tank overheated Thursday and began venting vapors at the company’s site in Garden Grove, about 40 miles (60 kilometers) south of downtown Los Angeles, according to the fire department.
No injuries were reported. Air monitoring tests found air pollution around the evacuation area was within normal limits, and specialized equipment was deployed to ensure no gas was released from the damaged tank, state and federal environmental officials said. He said Saturday.
Streets were empty in the area on Sunday, according to aerial photos taken by the Associated Press.
A crack could be a welcome development, because it could mean a release of product or pressure inside the tank, reducing the chance of the tank exploding, said Andrew Welton, an engineering professor at Purdue University.
“Think of a soda can. If you leave it in a hot car, it can explode,” he said. “But if you make a hole in the can, the product will be released and the can itself will not explode.”
Elias Picazo, a professor of chemistry at the University of Southern California, agrees that a rift could be a positive development.
“A strategic leak provides more time for the liquid inside the tank to solidify as the reaction continues,” he said. “Depending on the location of the leak, it can also be used to direct unreacted liquid out of the tank in a controlled manner.”
Faisal Khan, head of the Department of Chemical Engineering at Texas A University&U of M said the presence of a crack indicated an explosion could still occur, but not on the scale that was initially feared.
“Cooling occurs at the surface of the tank while a runaway reaction may occur deep within the tank,” he explained. “Yes, the reaction is slower compared to when it started. However, we are not out of danger of launching explosives.”
Many shelters remained open for displaced people. The parking lot was full Sunday at a high school evacuation center in nearby La Palma. Some people, including a family of seven, slept in cars or on mats and sleeping bags on the asphalt. The large family also had nine cats. They assembled cat carriers for a makeshift table while they waited, drinking coffee and grooming the pets.
Meanwhile, some Garden Grove residents filed a class-action lawsuit Saturday against GKN Aerospace Transparency Systems, the company that operates the facility where the tank is located.
No matter what happens next, property values in the surrounding community are sure to be affected, attorneys for residents living in the eviction zone said in their lawsuit in federal court.
Company spokespeople did not comment on the lawsuit itself, but pointed to a statement issued on Saturday in which they apologized to residents and businesses that had to evacuate.
On Sunday, the company issued another statement in which it said it was monitoring “the condition of the affected materials” and “working around the clock to mitigate the risk of leakage.”
Officials said valves in the tank were broken or “sticked,” preventing crews from removing the chemical or relieving pressure on the tank, said Craig Coffey, Orange County Fire Authority division chief.
Firefighters’ first hope is to find a way to cool the chemical inside the tank so it doesn’t leak or explode. If that’s not possible, Wilton said it would be better to have a leak in the tank so that most of the chemical can be contained. An explosion that could spread the chemical over a wide area and send shrapnel flying would be the worst-case scenario.
If the temperature inside the tank continues to rise, the pressure will continue to increase as the methyl methacrylate turns from a liquid to a gas. Firefighters were unlikely to consider punching a hole in the tank because of concerns that doing so would create a spark that could ignite the volatile and flammable gas, Welton said.
Drones were monitoring temperatures at 10-minute intervals to monitor for any spikes, Coffey said in a social media post on X. Containment barriers have been set up to prevent the chemical from getting into storm drains or reaching streams or the nearby ocean if a leak occurs, Coffey said.
The damaged tank is located at GKN Aerospace, which makes parts for commercial and military aircraft. It contains between 6,000 and 7,000 gallons (22,700 and 26,500 liters) of methyl methacrylate, used to make plastic parts.
GKN agreed to pay more than $900,000 to state regulators in 2025 to settle record-keeping violations, permit issues and nitrogen oxide emissions, according to a report on the South Coast Air Quality Management District website.
Exposure to methyl methacrylate can cause serious respiratory problems and even render a person unconscious. It can also cause neurological problems and irritate the skin, eyes and throat, according to a fact sheet about the chemical. But Orange County health officials said the chemical is easy to smell and residents may notice it over a large area without being harmed.
Wilton said the volume of the chemical in the tank is much lower than it was in the disastrous year of 2023 A train derailment in East Palestine, Ohio Which he studied when more than 115,000 gallons (435,000 liters) of vinyl chloride were released after officials blew up five tank cars and burned the chemical.
“Many of these effects are acute and fast-acting. But the longer a person is in contact with them, the greater the potential for significant harm,” Wilton said.
If an explosion released the chemical into the air, Wilton said, it would be necessary to conduct detailed air monitoring specifically for methyl methacrylate, not just general tests for volatile organic compounds as officials did in East Palestine.
Weather will be an important factor in determining where the plume of chemicals will go in the event of an explosion. Officials were developing maps to predict different scenarios.
Garden Grove is located next to Anaheim, home to the two Disneyland theme parks, which were not under evacuation orders. Park officials said they are monitoring the incident and are supporting employees affected by the evacuations.
___
Marcelo reported from New York. Associated Press journalist Ethan Swope contributed to this report.