Tens of thousands of people were ordered to leave their homes in California on Friday after a huge chemical tank began leaking, with warnings it might blow up, sending toxic fumes over a heavily populated area.
The tank contained 26,000 litres of methyl methacrylate, a volatile and flammable liquid used to make plastics, with firefighters warning the situation was looking grim.
“There are literally two options left,” Incident Commander Craig Covey said.
“The tank fails and spills a total of about 6-7,000 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", he added.
Covey mentioned, “We are setting up these evacuations in preparation for these two options: it fails, or it blows up.”
“Please follow our requests and orders for evacuations,” he emphasised.
The incident was unfolding in the Garden Grove area of Orange County, southeast of Los Angeles.
Garden Grove Police Chief Amir El-Farra said the evacuation order affected about 40,000 people, and several thousand refused to leave their homes.
Local TV stations filmed aerial footage that showed jets of water spraying at the tank, which has a capacity of 34,000 gallons.
Orange County health officer Regina Chinsio Kwong said that the large exclusion zone around the tank was a necessary precaution.
“If it does explode and there is a vapour, you are all safe as long as you are out of the zone that was determined to be an evacuation zone,” she said in a video update.
She appealed for anyone who might notice 'a fruity and heavy smell' to alert the authorities.
“Smelling it does not mean you have reached a level that causes symptoms. But we don’t want you to smell that. So, we need to know if you are smelling it,” Regina continued.
No injuries had been reported by Friday afternoon, and there was no immediate indication as to what caused the leak, which was initially reported on Thursday.
Covey said again, “crews were preparing for a chemical spill, which he described as a “best-case scenario” and far preferable to an explosion and toxic plume.”
Responders were working to put containment barriers in place to prevent any spilt material from reaching storm drains or river channels that funnel into the ocean.
The US Environmental Protection Agency says methyl methacrylate is irritating to the skin, eyes, and mucous membranes in humans.
“Respiratory effects have been reported in humans following acute (short-term) and chronic (long-term) inhalation exposures,” a fact sheet on the agency’s website mentioned.
“Neurological symptoms have also been reported in humans following acute exposure,” it added.
