Mobil Refinery Explosion Rekindles Safety Debate
Two days before Thanksgiving, a thunderous explosion shook Mobil Oil Corp.'s refinery in Torrance, sending refinery workers running for cover and igniting a spectacular fire that burned for two days.
Furious flames fueled by a rich mixture of propane and butane soared into the night sky, snarling traffic on major streets and the nearby San Diego freeway.
The blast, which was heard for miles around, shattered windows in nearby homes and businesses, stained cars with a petroleum residue and caused millions of dollars in damage to the refinery. Mobil has received at least 250 property damage claims from neighbors, but only four people at the refinery suffered minor injuries.
Mobil has apologized for any inconvenience the explosion may have caused and has sought to reassure the community that safety is its highest priority.
But the Nov. 24 explosion has rekindled a debate about whether a major refinery processing millions of gallons of gasoline, diesel, jet and other fuels daily can operate safely in a densely populated urban area.
Members of the Torrance City Council want that question answered.
It is the same question that was asked in December, 1979, after an explosion and fire at Mobil killed two refinery workers and a passing motorist when her car ignited a vapor cloud that had drifted from the tank farm at Van Ness Avenue and Del Amo Boulevard.
“They are a major landowner right in the center of our city,” Torrance Mayor Katy Geissert, said last week. “We certainly have a responsibility to the public to do whatever is within our authority to ensure a safe operation.”
The concerns about safety grew when Mobil announced late Friday that the explosion was caused by too much lethal hydrofluoric acid in a refinery unit.
“It certainly heightens our concern about how the hydrofluoric acid is being used, controlled and contained,” Geissert said.
After investigating, Mobil found that the explosion and fire started in a propane treater in part of the refinery called an alkylation unit.
The 30-foot-tall alkylation unit removes water and other impurities from fuels while producing gasoline, propane and butane. The propane treater is designed to remove small amounts of acid from liquid propane.
Mobil blamed the excess acid in the propane treater on “malfunctioning instrumentation” in the alkylation unit. The resulting reaction “created abnormal pressure” in the propane treater vessel, “causing it to rupture,” the company said. Pieces of the exploding vessel then severed nearby pipelines, fueling the fire.
“The hydrofluoric acid never escaped off the property,” said Thomas Gregory, the refinery’s manager of safety and training. “There was no danger to the public.”
The Environmental Policy Institute in Washington reported earlier this month that 58 U.S. oil refineries, including Mobil and two others in the Los Angeles area, use hydrofluoric acid.
The environmental group warned that a major accident that released hydrofluoric acid could pose as serious a danger as the methyl isocyanate leak at a Union Carbide plant in Bhopal, India, that killed more than 2,000 people in December, 1984.
The group said tests conducted last year in the Nevada desert for the oil industry by the Lawrence Livermore National Laboratories show that a 1,000-gallon release of hydrofluoric acid could “produce a toxic gas cloud lethal to all human beings exposed within a range of five miles from its release point.”
The nonprofit organization said hydrofluoric acid forms a dense cloud that hugs the ground and moves with the wind away from the accident site.
In October, more than 60 people were injured and 3,000 residents were evacuated in Texas City, Tex., when a hydrofluoric acid leak at a Marathon Oil Co. refinery sent a vapor cloud over the city.
Nearly 500,000 people live within five miles of the Mobil refinery.
Mobil refinery manager Wyman D. Robb said the environmental group “largely overstated” the risk involved. Robb said Mobil workers are trained in the handling of the chemical and any emergency that might arise.
About 250,000 pounds of the acid is now stored in vessels at the Torrance refinery, down from a peak of 450,000 pounds, according to Mobil.
Robb said the acid is used at the refinery as a catalyst to boost the octane in gasoline. “We have been using this process at the Torrance refinery for over 40 years,” Robb said. “We have never had a serious incident where the acid has been emitted into the community.”
“We have an awful lot of respect for it,” Robb said. “We have designed and built our process units with the utmost of safety.”
In addition, the company has pledged to install backup instrumentation before the damaged refinery unit is placed back in service.
In the event of a leak, Robb said Mobil now has the ability to spray enormous amounts of water where the leak might occur to contain it on the ground and neutralize it. Water combines with hydrofluoric acid, and spraying it would “knock the vapor down,” said Torrance Fire Chief Scott Adams.
The Torrance Fire Department received reports of two minor leaks of the acid in the days after the explosion, but both were contained on the site and no injuries resulted.
At the request of council members, Torrance officials last week launched a study to determine exactly what role the city plays in overseeing Mobil’s operation.
“Basically the council is asking, where do we fit into this picture,” Mayor Geissert said.
City Councilman Mark Wirth said he wants to know who is in charge.
“The Air Quality Management District has this little piece, the Occupational Safety and Health Administration has this little piece, and the City of Torrance has a little piece,” Wirth said. “But nobody has a good feel for the overall operation and what goes on there.”
A spokesman for federal OSHA in Long Beach, which covers Torrance, said the Mobil explosion was being handled by an inspector on loan from the Chicago area, but last week he returned to the Midwest.
Since federal OSHA assumed authority from Cal-OSHA for workplace safety, the agency has in some cases been using temporary employees transferred from other states, said George Godzak supervisor of OSHA’s Long Beach office.
“The person involved in the (Mobil) inspection has left us,” Godzak said, and a replacement has not been named. “The investigation is ongoing. We hope to wind this thing up in the near future.”
Wirth said he is also concerned about air pollution, noise, odors, the use of hydrofluoric acid and occasional flares in the refinery’s exhaust stacks.
He is not alone.
More than 50 demonstrators, many of them union members who no longer work on construction projects at Mobil, picketed the refinery during the morning rush hour Tuesday.
Beneath signs saying that “Mobil can be hazardous to your health,” protest organizer Dan Foley, a retired pipe fitter from Gardena, and other union members complained that Mobil is using non-union workers on construction projects at the refinery and that, they said, is a safety issue. The union members argued that the non-union construction workers, many of them from out of state, are not as skilled as union workers. Mobil rejected that argument, saying there is no safety hazard posed by the use of non-union workers on construction projects. Many of the 800 permanent Mobil employees who operate the refinery are members of the Oil Chemical & Atomic Workers International union.
Torrance Building and Safety Director Ralph Grippo said the city may hire a consultant to assess the risks posed by use of the chemical. Such a study would also examine the hazard
posed by sulfuric acid, which is used in some refineries as a safer alternative to the hydrofluoric acid.
Fire Chief Adams said coordination and training between Mobil’s firefighting personnel and the city’s firefighters has improved significantly since the 1979 accident. He pointed to an emergency drill in May that simulated a plane crashing into the Mobil refinery. The test involved Torrance and other South Bay fire departments, ambulance companies and hospitals, and the Red Cross.
“We have enjoyed a good relationship with Mobil’s fire safety people,” Adams said. “At this stage of the game, we have an ongoing, increasing understanding of their processes. They have demonstrated to us a substantial interest in their safety record.”