Chemical leak in Orange County has led to evacuations, concerns of potential explosion
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Around 40,000 residents have been asked to evacuate from parts of Orange County as a large industrial tank holding thousands of gallons of a highly-toxic chemical is at risk of exploding.
Several Los Angeles Times journalists visited Garden Grove and affected surrounding communities reporting on the situation that could have catastrophic consequences.
Let’s skip any more preamble and get into their work.
Timeline of events
Colleagues Salvador Hernandez, Clara Harter and Tony Briscoe wrote that the crisis began Thursday, when the Orange County Fire Authority initially responded to reports of a hazardous materials incident at a business in the 12000 block of Western Avenue in Garden Grove at 3:30 p.m
Upon arriving, they determined that methyl methacrylate, or MMA, a volatile liquid used to make plastic, was leaking out of a 34,000-gallon vat at GKN Aerospace.
The fire authority’s hazardous materials response team began dousing the tanks at a Garden Grove facility Thursday, prompting an initial evacuation order that was lifted later that day.
But on Friday morning, officials said a faulty valve and the inability to remove and neutralize the toxic chemical inside the tank had escalated the incident and left them certain that the large tank would, at some point, either fail, leaking thousands of gallons, or explode.
What’s being monitored?
The tank, holding about 6,000 to 7,000 gallons of chemicals, was described as being “in crisis” Friday.
“At that point, we know the tank is going into thermal runaway,” said Orange County Fire Authority Division Chief Craig Covey during a news conference Friday.
“There are literally two options left remaining. The tank fails and spills a total of about six 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 around them that have fuel or chemicals in them as well.”
What’s the game plan?
Colleagues Rong-Gong Lin II and Hannah Fry wrote that the main strategy is to do everything possible to keep the tank cool.
Firefighters on Friday reissued evacuation orders and expanded the zone to include portions of the cities of Garden Grove, Anaheim, Buena Park, Cypress, Stanton and Westminster. They warned that, at that point, the only two options ahead of them were either a massive leak or an explosion.
But they are buying time now using, cool sprinklers to try to keep the tank’s temperature down.
That’s a viable solution, said Elias Picazo, assistant professor of chemistry at USC, to “just wait it out by keeping the tanks cool. So by controlling the runaway, you can slow down the reaction and you can do your best to maintain the pressure.”
Covey said in an update on Friday night that efforts to cool the tank by spraying it with water have been successful so far.
“Those efforts are succeeding and it’s giving us [an] opportunity to reconsider engaging in close proximity to implement some of the concepts...to mitigate this thing,” he said.
By Saturday morning, Covey said that efforts to keep the tanks cool were failing, and that initial determinations that spraying the tanks was helping lower temperatures were not as effective as initially thought. By Saturday afternoon, Gov. Gavin Newsom declared a state of emergency over the incident.
What makes the chemical so dangerous?
Inside the tank is an estimated 7,000 gallons of MMA, stored in liquid form.
“It’s durable, lightweight, transparent, so it could even be used as a substitute for glass,” Picazo said of the final plastic product. The polymer can also be used in household goods as well.
The polymer itself isn’t toxic, but its liquid MMA predecessor — a monomer, essentially a bunch of single molecules — is. If it gets into the air, it can harm people at high concentrations and through chronic or extended exposure.
“The other hazard is the explosion itself. And it sounds like [the] reaction has already initiated, and that’s where the worry comes in for the explosion,” Picazo said.
Health risks for exposure
MMA is very toxic. Short-term exposure involving inhaling the chemical’s vapors “can cause significant irritation in the lungs, the nasal passages, and it can also cause nausea and it can also cause dizziness,” said Dr. Regina Chinsio-Kwong, Orange County’s health officer.
At very high levels of exposure, “it can really cause severe respiratory distress and hospitalization,” Chinsio-Kwong said.
Click here for more updates.
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Have a great day, from the Essential California team
Jim Rainey, staff reporter
Hugo Martín, assistant editor, fast break desk
Kevinisha Walker, multiplatform editor
Andrew J. Campa, weekend writer
Karim Doumar, head of newsletters
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