Powerine Oil Co.’s refinery in Santa Fe Springs does not have special equipment to handle a leak of highly corrosive hydrofluoric acid, according to a report presented Friday to the board of the South Coast Air Quality Management District.
And, based on information contained in the report, the special water spray safety systems at another Los Angeles-area refinery — Golden West Refining Co.’s facility in Santa Fe Springs — and at Allied Signal Corp.’s El Segundo chemical plant are not adequate to deal with a major leak, said David Schwien, a member of the air quality agency’s task force studying hydrofluoric acid.
According to the study, the Powerine refinery does not have a water spray system designed to mitigate a hydrofluoric acid release. The refinery, which typically has 9,600 gallons of the acid on hand, does have a firefighting water system. Powerine officials told the air quality agency that they intend to put in a water spray system but are waiting for the industry to make available newly designed equipment. Allied Signal and Golden West officials said they are planning to upgrade their systems.
Schwien said he compared the capabilities of safety systems at the five largest users of the corrosive chemical with data from the largest known release of hydrofluoric acid, a 1987 accident at the Marathon Oil refinery in Texas City, Tex.
In that accident on Oct. 30, 1987, about 7,000 gallons of the corrosive substance leaked out in a 100-minute interval after an 80-ton piece of equipment was dropped on a pipe leading to a tank containing the acid. About 650 people were injured, 3,000 were evacuated and trees were defoliated for miles. The EPA said last week that the Texas City accident had the potential of being as severe as the methyl isocyanate release in Bhopal, India, in 1984 that killed about 3,000 and injured about 200,000.
Schwien said refinery and industry data indicate that a release at the average spill rate in the Texas City accident — 70 gallons a minute — would overwhelm existing water spray safety systems at Allied Signal and Golden West.
According to the report, Allied Signal can handle releases of no more than 21 gallons a minute; the Golden West refinery in Santa Fe Springs can handle eight gallons a minute.
Mobil Oil’s Torrance refinery and Ultramar Refining’s Wilmington facility are the area’s two largest users of hydrofluoric acid. Both facilities have considerably larger water spray systems, although company officials acknowledged that a huge disaster — such as a plane falling on a hydrofluoric tank — could overwhelm their systems.
The five companies keep thousands of gallons of the acid on hand. Oil refineries use it as one of two possible catalysts — the other is sulfuric acid — to boost the octane number of unleaded gasoline. Allied Signal uses the acid to manufacture refrigerants.
The study presented Friday was the second update on the progress of the agency’s hydrofluoric acid task force, formed in January, 1988, after two accidents involving the corrosive chemical to study whether to regulate or eliminate use of the acid in the Los Angeles area.
The Marathon Oil accident was one of the accidents focusing attention on hydrofluoric acid. The other was a thunderous explosion and two-day fire at Mobil’s Torrance refinery in November, 1987, during which 100 pounds of the substance was released.
Could Be Lethal
According to industry-sponsored tests conducted in the Nevada desert in 1986, a release of hydrofluoric acid forms a dense, ground-hugging cloud of gas and small droplets that, following a two-minute, 1,000-gallon spill, could prove lethal as far as five miles downwind. Follow-up tests in Nevada in 1988 showed that water sprays must drench the acid in a 40-to-1 ratio of water to acid to reduce toxic fumes by 90% — a comparatively safe level.
Using the 40-to-1 standard, the report said, the best water spray system currently operating at major hydrofluoric acid users in the Los Angeles area is a 9,000-gallon-a-minute system at the Ultramar refinery, which could handle a leak of 225 gallons a minute. At Mobil’s refinery, the water spray system could take care of a hydrofluoric acid leak of 78 gallons a minute.
No agency working on risk assessment for hydrofluoric acid has determined exactly how big a water spray system should be to handle disasters. But Schwien said the Texas City accident offers a valid case study.
“It is not fiction. It is not fantasy. It happened. Three of these systems — at Powerine, Golden West and Allied Signal — appear not to have (water spray) systems able to handle the sort of accident that happened at Marathon Oil. In that accident, according to refinery figures, the average spill rate was about 70 gallons a minute.”
Allied Signal plant manager Joseph Barnett said, “While it is true that our system could not handle a leak of 70 gallons a minute, the sort of leak that occurred at Texas City is very unlikely because of precautions we have taken.”
Golden West refinery manager John Miller said the facility was beginning a risk study at the request of the city of Santa Fe Springs.
At Ultramar, refinery manager Marshal A. (Bud) Bell acknowledged that “you can conjure up a scenario that nobody, including us, can handle.”
“But in the real world,” he added, “when we did our disaster scenario modeling, the most credible leak we came up with was a pump seal failure.” Bell said that Ultramar’s water spray system easily could handle that sort of hydrofluoric acid leak.
At Mobil, refinery officials are increasing their water system and are planning to install large holding tanks to drain acid rapidly from processing units in the event of a rupture.