Potential crack on California toxic chemical tank could be easing pressure as officials race to prevent explosion

LA PALMA, California. — A potential crack could release pressure inside a toxic chemical tank in Southern California, officials said Sunday, a development they hope could help avert a devastating steam explosion.

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The possible crack was identified during a visual inspection of the 7,000-gallon tank Saturday evening at the GKN Aerospace facility in Garden Grove, Acting Orange County Fire Chief TJ McGovern said Sunday.

“With this new information, it could change our trajectory and strategy for this event,” he said, noting that teams are reviewing and validating the information.

The tank contains methyl methacrylate, a toxic chemical used to make resins and plastics. Concerns about a possible explosion or leak have prompted evacuation orders for tens of thousands of residents, many of whom remain in shelters.

McGovern told NBC News that crews were looking to confirm that the crack was releasing pressure in the reservoir. If so, this means “the potential for a BLEVE [boiling liquid expanding vapor explosion] is now out of the question.

“There is always the potential for an explosion,” he said, but not a BLEVE, which he described as “very, very dangerous, much worse than an explosion.”

If a BLEVE is still possible, the evacuation area will be much larger, but if that problem is ruled out, the evacuation area can be smaller and crews will then focus on cooling the tank, he said.

McGovern added that air monitoring showed the possible crack did not result in a release of toxic air.

A GKN Aerospace spokesperson said Sunday that the company was monitoring the status of “affected equipment” and that teams were working “around the clock to mitigate the risk of a leak.”

If the tank explodes, it could also trigger an explosion in a nearby 15,000-gallon tank and a 4,500-gallon tank also containing methyl methacrylate, Division Chief Craig Covey, commander of the Orange County Fire Department, told NBC News Saturday.

Officials also fear the reservoir could rupture and release toxic materials into waterways.

“We’re talking about probably one of the worst chemical incidents in California history,” Covey said.

Authorities say the blast radius, which extends up to 800 meters, would cause severe structural damage and most likely disperse toxic vapors into the air.

Orange County shelters are filling with distraught residents as 50,000 people are under evacuation orders.

Lydia Green, who lives in Anaheim, about a mile from the facility, is one of them.

“I feel nervous, scared, devastated,” Green told NBC News on Sunday at a shelter at John F. Kennedy High School in nearby La Palma. “I was deprived of my medication, of my basic needs: food, hotels, we didn’t have a hotel. It was very hard.”

She and her partner, Eugene Smith, were asleep in their car. Smith described the ordeal as “like living in a nightmare” and he fears a devastating explosion and its aftermath.

“Blowing up and then contaminating everything. Everything. This is where we live. This is our home,” he said.

Jaden Gebeleinis was also at the shelter and said he was nervous because he lives on the edge of the evacuation zone.

“It’s a lot of anger. (…) I wonder why there are these facilities right next to a bunch of houses? And that annoys me too,” he said. “You hope it’s handled well and the worst-case scenario doesn’t happen, because these are people’s homes, and it’s probably going to affect a much larger radius than they’re letting on.”

The American Red Cross said Sunday that six shelters scattered across the region for evacuees were close to accommodating or at full capacity for overnight stays.

McGovern said there is no timetable yet for when residents will be able to return home.

The concern first emerged Thursday with “steam release” from the 7,000-gallon tank, Orange County firefighters said. Further investigation revealed that the temperature of the tank was increasing.

Firefighters used sprinklers and hoses to cool the tank. McGovern said that during a team operation Saturday evening, crews saw that the needle on the temperature gauge was reading 100 degrees Fahrenheit, the highest level it indicates, meaning actual temperatures in the tank could be higher.

Garden Grove is in northern Orange County, about 35 miles southeast of Los Angeles and 4 miles from Disneyland in Anaheim.

Governor Gavin Newsom declared a state of emergency in Orange County on Saturday. On Sunday, he asked President Donald Trump to issue an emergency declaration to support response operations in the county.

McGovern said officials worked collaboratively and used “out-of-the-box thinking” to find a solution and get families back into their homes.

“We have to get them back,” he said, “but I assure you we won’t get them back until we can do it safely.” »

Steve Patterson and Shanshan Dong reported from La Palma and Marlene Lenthang from Los Angeles.