Authorities urgently try to stop California chemical tank explosion; 50,000 under evacuation orders
Authorities are urgently trying to stop an overheated, pressured and bulging tank filled with a toxic chemical from exploding in Orange County, California.
In what is being called an "unprecedented" situation, tens of thousands of people in the area were told to leave their homes Friday, with officials issuing a dire warning that the chemical tank, located at an aerospace facility, is in "crisis" and will either spill or explode.
"This is as real as it gets. It's the worst-case scenario I've ever faced in my career," Orange County Fire Authority (OCFA) Division Chief Craig Covey told ABC News on Saturday from the command center outside Garden Grove, teeming with first responders intent on preventing an environmental disaster.
Garden Grove is located about 30 miles south of Los Angeles.
In a Sunday afternoon update, OCFA Interim Chief TJ McGovern said firefighters did "a recon mission on the tank" late Saturday night during which they were able to visually inspect it.
"What they found was a potential crack in the tank, which could potentially be relieving some of the pressure in there," McGovern said, adding that they were now "vetting and validating" the new information, which "could change our trajectory and our strategy to this event."
The OCFA said in a subsequent update that any areas outside of the evacuation zone "are currently considered completely safe and day-to-day activities can continue as normal."
"We continue to monitor the condition of the affected material and are working round the clock to mitigate the risk of a leak," a spokesperson for GKN Aerospace manufacturing company in Garden Grove, which is the tank's location, said in a statement to ABC News. "We are acutely aware of the uncertainty this incident is causing and sincerely apologize for the ongoing disruption to the local community."
The statement further said that GKN was working closely with local, state and federal agencies to address the situation.
"Our priority remains the safe resolution of this incident, so that residents can return to their homes as quickly as possible," the statement said.
On Saturday, California Gov. Gavin Newsom issued a state of emergency in Orange County in response to the incident.
"The safety of Orange County residents is the top priority," Newsom said in a statement Saturday. "We are mobilizing every state resource available to support local responders and make sure the community has what they need to stay safe."
Looming over the roughly 10-square-mile evacuation zone now are both concerns that either toxic fumes could waft through the neighborhood, or that a dangerous fireball could erupt, according to an internal briefing memo reviewed by ABC News.
50,000 under evacuation orders
Mandatory evacuations have expanded for the estimated 50,000 residents in the densely populated area, the memo said. There are multiple public facilities nearby -- including schools, hospitals, nursing homes, fire and law enforcement stations -- critical infrastructure, and essential services, all currently subject to mandatory evacuation and ongoing response operations.
Multiple roads have also been closed off in the evacuation zone, changing transportation routes in the area. Evacuation centers have been established across Garden Grove, Cypress, Stanton City Hall, Anaheim, and Buena Park, the memo said.
Over a dozen schools have temporarily closed, and those adjacent to the evacuation area canceled outdoor activities "out of an abundance of caution," the Garden Grove Unified School District said.
Despite efforts overnight to cool down the tank, the temperature climbed from 77 degrees to 90. Covey confirmed the two scenarios that could play out: either a massive fireball erupts or the chemical leaks out, impacting the thousands of residents forced to evacuate.
Efforts to stop disaster: 'There's no precedent on this'
Asked about the timeline for when the situation could be resolved, Covey said: "We have no idea. Everybody asked me that question and I would love to give you an answer. There's no precedent on this. No one knows."
Officials are prepared for a potential chemical leak by diking, damming and diverting the flow of chemicals, which is the preferred option compared to an explosion -- but even that could prove to be complicated.
“If we burn down a bunch of buildings and a bunch of homes, that's a disaster," Covey said. 'But if we allow this to make it to the ocean and make it an ecological disaster, we don't want that as well."
How the situation unfolded
Firefighters initially responded to a leak at the GKN Aerospace manufacturing company in Garden Grove on Thursday, for vapor releasing from a 34,000-gallon tank containing methyl methacrylate, which is used in plastic manufacturing, according to the Orange County Fire Authority.
Authorities first issued an evacuation order on Thursday, but that was later lifted when vapor conditions improved. However, the evacuation orders were reissued and expanded on Friday due to what police called an "unprecedented" event.
On Friday, the situation had grown more dire, with officials warning that, though there was no active gas leak or plume, the tank was "actively in crisis" and unable to be secured.
Three tanks affected
Three tanks are affected at the GKN site, according to the internal briefing memo. Of most concern is Tank #1, which has the malfunctioning valve that, so far, is unable to be neutralized. That valve has seized due to the chemical reaction inside the container. Firefighters have been trying to get the temperature down and stable with water cooling.
Meanwhile, emergency responders on scene have been trying to troubleshoot Tank #2 -- which contains the same chemical as the other, compromised tank. Officials on scene have added a "neutralizer" to the methyl methacrylate in Tank #2 to prevent an even worse chain reaction. That tank appears to be structurally sound, the memo said.
Tank #4 is also structurally sound, however the status of what's inside it is "unknown."
Local fire and HAZMAT teams are on-site working to cool the 34,000-gallon industrial vessel and clean up, with investigation efforts underway, the memo said, with state emergency resources also partially activated. The EPA has also dispatched two on-scene coordinators to the facility.
The response remains active, and so far no injuries have been reported, the memo said.
Official: 'It fails or it blows up'
At a press briefing Friday, authorities laid out the urgency of the situation.
"There are literally two options left remaining: one, the tank fails and spills a total of about 6- to 7,000 gallons of very bad chemicals into the parking lot in that area. Or two, the tank goes into a thermal runaway and blows up, affecting the tanks that are around them that have fuel or the chemicals in them as well," Covey said in a video update Friday.
He added, "We are setting up these evacuations in preparation for these two options -- it fails or it blows up," he said.
Officials have said it is unclear when residents will be able to return to their homes.
"This is highly volatile, it's highly toxic, it's highly flammable," Covey said during an earlier press briefing, while urging people to evacuate. "This is not precautionary. This is gonna happen unless some brilliant guy behind me here figures out how we can mitigate this incident. This thing is gonna fail -- we don't know when."
What is methyl methacrylate?
Methyl methacrylate is an industrial chemical used in plastics and manufacturing and is primarily a respiratory irritant, authorities said. Around 7,000 gallons are estimated to be left in the tank that's in crisis, Covey said.
Short-term exposure to the chemical can cause skin and eye irritation, as well as breathing problems, according to the EPA.
Orange County Health Officer Regina Chinsio-Kwong said in a video update Friday evening that an explosion could cause the chemical to be released as a vapor, which, if inhaled, could cause "severe respiratory issues." Other symptoms include a sore throat, runny nose, itchy and burning eyes, and potentially nausea and headache, she said.
GKN Aerospace builds engines and landing gear for both commercial and military aircraft. ABC News has reached out for comment.
In a video posted to the Orange County Fire Authority's X account, Jason Lo of the South Coast Air Quality Management District said that levels of pollutants around the evacuation zone were "completely normal."
Harry Allen of the EPA said the agency began stationary air monitoring on Friday, deploying 24 stationary monitors that are "operating around the clock."
No contaminants have been observed by the monitoring stations, which will continue to operate until the scene is secure, Allen said. Specialty equipment is also in place to ensure that no gas is released from the tank at the source of the incident, Allen added.
Pollutant levels in the air around the evacuation zone remained "completely normal" as of Sunday morning, Allen said.
ABC News' Sasha Pezenik, Bonnie McLean, Josh Margolin, Jenna Harrison, Jack Moore, Amanda Morris and Bennett Garcia contributed to this report.
