A huge explosion that ripped through an ExxonMobil oil refinery in California last year nearly sparked a chain reaction which would have caused thousands of pounds of acid to leak out.
The blast, which saw an 80,000lb piece of equipment blown clear of the refinery and the surrounding neighborhoods covered in dust, could also have been prevented, a new government report says.
Managers should have taken into account ageing safety equipment and shut down a key part of the refinery before attempting to carry out repairs elsewhere, the U.S. Chemical Safety and Hazard Investigation Board said.
Aftermath: A vehicle is covered in ash after an explosion last year in a processing facility at the ExxonMobil refinery in Torrance, California. The blast, which saw an 80,000lb piece of equipment blown clear of the refinery and the surrounding neighborhoods covered in dust, could also have been prevented, a report says
Four contractors were injured and a large part of the refinery in Redondo Beach was destroyed on February 18 last year after a fireball tore through the facility.
According to today’s report, the blast was caused when a unit being repaired after five years without maintenance leaked dangerous hydrocarbons into another part of the refinery.
That caused a spark which in turn set off the explosion, ripping a large hole in the outside of the building and sending equipment flying.
But while the impact of that explosion was dramatic, it could have been far worse, investigators said.
According to the report, equipment blown clear of one part of the refinery in the blast landed near a second unit which contained thousands of pounds of modified hydroflouric acid.
The chemical is highly corrosive, as can be seen in hit series Breaking Bad, where it is used by protagonists Walter White and Jesse Pinkman to dissolve the bodies of those they kill.
The blast also disabled a column that contained a laser sensor that was designed to alert operators to any leak in those tanks.
With the safety system disabled, if any damaged had been caused to the hydroflouric acid tanks, it could have caused a devastating spillage, the report concludes.
Up in flames: Flames leap from a burner unit after an explosion at the Exxon-Mobil refinery in Torrance, California, February 18, 2015. An explosion and fire at Exxon Mobil Corp’s Torrance refinery sent ash spraying on nearby cars and burst windows of surrounding buildings
Vanessa Allen Sutherland, chairwoman of the Chemical Safety and Hazard Investigation Board, said: ‘What we definitely believe is that this was a serious near-miss incident.’
‘That amount of HF [modified hydroflouric acid] — or even a portion of the HF — had the potential to vaporize and cause some injury.’
The lack of layered safety precautions mirrors the cause of a 2012 fire at a Chevron refinery in Richmond, California, that sent more than 15,000 residents to the hospital and endangered 19 workers, the agency said.
Sutherland also criticized Exxon, saying the firm refused to provide federal investigators with nearly half of the documents they requested for the preliminary probe, specifically those related to the acid.
The company has provided 136,000 pages of material to the board, but not any related to the acid Todd Spitler, a spokesman for the company, said.
Damger: Vanessa Allen Sutherland, chairwoman of the Chemical Safety and Hazard Investigation Board, said: ‘That amount of HF [modified hydroflouric acid] — or even a portion of the HF — had the potential to vaporize and cause some injury.’ Pictured here are flames coming from the refinery last year
Exxon disputes the findings in the 2015 blast and has stringent safety rules, Spitler said. An internal review found no protocols were violated, he added.
‘ExxonMobil stands on its record of good faith compliance with all agencies, including the chemical safety board, and we look forward to reviewing the preliminary report,’ Spitler said in a statement.
Exxon maintains that the federal agency, which serves a watchdog role and has no regulatory authority, does not have jurisdiction to investigate anything but the cause of the blast itself.
The U.S. Department of Justice will help the investigative agency enforce subpoenas to get the files, Sutherland said.
Damage: Refinery units were heavily damaged after the explosion at the Exxon-Mobil refinery in Torrance, California, February 18, 2015. According to Wednesday’s report, the blast was caused when a unit being repaired after five years without maintenance leaked dangerous hydrocarbons into another part of the refinery
ExxonMobil sold the refinery to New Jersey-based PBF Energy Inc. in September. Continued repairs have delayed the closing of the deal.
California workplace regulators issued $566,000 in fines last summer for health and safety violations related to the blast. The plant is located in a densely populated area of the city of Torrance, about 20 miles southwest of Los Angeles.
The fluid catalytic cracker unit where the blast occurred is critical to producing California-grade fuel. The special blend means the state typically has the highest gas prices in the U.S.
Exxon is appealing Cal OHSA’s findings.
Federal investigators agreed that serious safety deficiencies led to the blast that occurred when Exxon shut down the fluid catalytic cracker unit to do repairs.
With the unit down, Exxon pumped steam in to prevent hydrocarbon gas from seeping out, but workers complained about the steam and so the volume being pumped was reduced, said Mark Wingard, the board’s investigator-in-charge.
Dispute: Todd Spitler, a spokesman for the company, said that Exxon disputes the findings in the 2015 blast and has stringent safety rules
The reduction was in line with a similar repair plan used in 2012, but aging equipment changed the scenario and Exxon did not test to make sure the lesser steam pressure was still sufficient to prevent a leak, Wingard said.
A valve that had not been checked in five years failed and allowed the hydrocarbons to seep through the system until they reached an electrostatic precipitator, where a spark ignited the gas and caused the explosion.
If Exxon had shut down the electrostatic precipitator, the accident never would have happened, Wingard said.
In addition, investigators found five or six pieces of equipment — including the faulty valve — that failed because they had not been maintained, he said.
A full maintenance overhaul was due in June, four months later.
Exxon managers also failed to talk to workers who knew the valve was faulty, said Don Holmstrom, western regional director of the chemical safety board based in Denver.
Two other recent incidents at the Torrance plant have frayed nerves.
In September, the Fire Department reported a leak of modified hydrofluoric acid, and a month later, a leak in a pressurized pipe caused a large steam cloud above the refinery as sirens urged residents to shelter in place.
ExxonMobil said it was mostly steam that leaked. A state investigation is pending.
The refinery on 750 acres produces 1.8 billion gallons of gasoline a year, which accounts for about 8.3 percent of the state’s total refining capacity.