California seeks solution as Los Angeles chemical tank heats up

With pressure building inside a tank of hazardous chemicals in Southern California, firefighters racing to stop an explosion or toxic leak have turned to outside specialists in a bid to avert disaster, as several nearby shelters filled up with evacuees.

Evacuation orders stayed in force across a zone affecting tens of thousands of residents in Garden Grove, a Los Angeles-area suburb.

California Governor Gavin Newsom declared a state of emergency in Orange County, while his office urged residents to comply with evacuation instructions.

“We have brought in subject matter experts from all across the state to think completely outside the box, and we had some really good productive conversations today,” Craig Covey, division chief of the Orange County Fire Authority, said in a video posted on social media.

Officials switch to more aggressive strategy as danger intensifies

Evacuation shelters in Anaheim, Fountain Valley, La Palma and Huntington Beach were reported to be full.

Fire crews re-entered the hazard area overnight after drone data on Friday indicated that water being sprayed on the tanks was helping keep conditions stable, Mr Covey had said earlier.

But once responders reached the tank’s gauge, they discovered the temperature inside had climbed to 32C, from 25C when crews had previously withdrawn.

He said the reading was rising by about one degree every hour. “That’s the bad news.”

Since Friday, officials have warned that the tank, which holds methyl methacrylate, a flammable chemical used in plastics and manufacturing, could rupture, release as much as 26,500 litres of toxic material, or explode and threaten nearby tanks.

Many Los Angeles evacuees spent the night in evacuee centres

Mr Covey said firefighters were examining whether a sustained stream of cooling water could slow the curing process inside the tank enough to ease pressure and stop an explosion.

“Letting this thing just fail and blow up is unacceptable to us,” he said.

The emergency began on Thursday at the GKN Aerospace facility in Garden Grove, a city of about 172,000 people roughly 50 km south of Los Angeles.

According to its website, the site focuses on manufacturing and testing windows and canopies for commercial and military aircraft.

GKN said it was working with “all relevant experts” to resolve the situation.

“We sincerely apologise for the significant disruption to the many local residents and businesses who have had to be evacuated,” a GKN spokesperson said in a statement.

Mr Covey said crews moved overnight from a “defensive” posture to an “offensive” operation, aided by chemists from the manufacturer’s emergency response team.

The objective was to neutralise a nearby 15,000-gallon tank and lessen the risk of an explosion if the smaller tank failed.

“We did put people in harm’s way last night,” Mr Covey said.

Health officials have said they were worried vapour from the chemical could trigger serious respiratory problems after prolonged exposure.

Air-quality monitors, however, had not detected vapour in the latest health update referenced by officials.

“You are safe as long as you are out of the zone that was determined to be an evacuation zone,” Dr Regina Chinsio-Kwong of the Orange County Health Care Agency said on Friday.

Mr Covey said crews were also preparing for the possibility of a spill by identifying ways to dike, dam and divert the liquid into a holding area on the commercial property, instead of allowing it to flow into storm drains, river channels or the ocean.

“We are not giving up,” he added.