The underground breaks that dumped thousands of gallons of gooey, foul-smelling crude oil onto the streets of the San Fernando Valley in recent weeks marked at least the fifth and sixth times the high-pressure Mobil Oil Corp. pipeline has ruptured in the last 2 1/2 years.
“That’s unusually high,” said Walter Hernandez, a pipeline expert with the state fire marshal’s office that is investigating the breaks. “We’re concerned.”
At least four of the breaks in the 187-mile line apparently were caused by corrosion that weakened the steel pipeline until it burst under pressures that routinely range up to 1,300 pounds per square inch.
One concern of the state investigators is the fact that less than a year ago Mobil tested the line in accordance with federally mandated standards and found nothing wrong.
Not Pointing Finger
Hernandez is not pointing an accusing finger at Mobil. Instead, he is calling for a harder look at a little-understood phenomenon--corrosion problems caused by the proximity of petroleum pipelines to other metallic pipelines and conduits.
The National Transportation Safety Board warned last year that federal safety requirements are inadequate to assure that corrosion protection systems are working properly. In response, the National Assn. of Corrosion Engineers is reviewing the methods being used to evaluate corrosion protection systems. The association’s recommendations are expected by the end of the year.
Another concern has been the lack of check valves at regular intervals along the line. Safety officials have suggested that such valves would reduce the amount of oil that would drain out of a line in the event of a break. While no one disputes this point, the federal Department of Transportation has concluded that such valves would be prohibitively expensive.
But despite these concerns, the safety officials, the Department of Transportation and industry spokesmen all agree on one thing: Pipelines today are still the safest, most cost-effective method of transporting hazardous materials such as liquid petroleum products.
Federal accident figures show that between 1982 and 1985, moving petroleum by pipeline was about 50 times safer than moving it by truck and about 135 times safer than moving it by rail.
Mobil estimates that it would take a fleet of more than 600 tanker trucks making round trips each day to transport the approximately 2.6 million gallons of crude oil it pumps daily through the line that runs from production fields in Kern County to its 800-acre refinery in Torrance.
“Just imagine all those trucks coming down I-5,” said Tim Salles, manager of West Coast Pipe Lines, the Mobil subsidiary that operates the line. “What would you have then?”
Mobil is but one of eight companies--most of them major petroleum retailers--that operate large pipeline systems in the Los Angeles area, and there have been dozens of other pipeline failures in the area over the years. A few involved lines carrying highly volatile petroleum products--jet fuel, gasoline and naphtha--and when they broke, the results were disastrous.
On June 15, 1976, gasoline from an underground line in the Palms-Culver City area exploded into flame after the line was accidentally ruptured by workmen using excavation equipment. The resultant fire demolished a block of buildings along Venice Boulevard, killing nine people and injuring 120.
On Nov. 30, 1980, a pipeline under the streets of Long Beach failed under pressure, spewing highly volatile naphtha into the air. In the resultant fire, at least 10 homes were destroyed, nine more were damaged and two people were seriously injured.
Mostly Crude Oil Lines
But most of the breaks have involved the crude oil lines that account for about 90% of the approximately 2,000 miles of major petroleum pipeline in Los Angeles County. Because crude oil is hard to ignite, none of these crude oil breaks posed much of a threat to human life.
On the other hand, crude oil is messy, it can pollute both soil and water and is toxic to wildlife.
While only one death resulted from pipeline breaks in the United States in 1986, property damage that year totaled more than $15 million.
The break in the Mobil line on Sept. 10 dumped about 93,000 gallons of crude that flowed for four hours down Ventura Boulevard in Encino, slathering sidewalks, driveways and automobiles with a thick layer of black goo that eventually seeped into storm drains.
Some of it emptied into the Los Angeles River, draining as far as Long Beach. More than 200 ducks in the river were coated with oil, and many of them died.
Mobil, which organized much of the cleanup effort, estimated the cost of that effort at well over $1 million.
No one has totaled up the overall cost of seven breaks along the Mobil crude oil line that have been chronicled over the last 15 years. These ruptures include:
- Oct. 18, 1973. The line, apparently weakened by corrosion, broke in Westwood during a routine pressure test, dumping about 84,000 gallons of oil onto Wilshire Boulevard. The oil flowed east for four blocks, into the underground storm drain system, eventually ending up in Ballona Creek, six miles to the south.
- April 7, 1986. The line broke in Granada Hills, apparently because of corrosion, dumping about 29,000 gallons of oil into Bull Creek. The oil flowed down the creek and into the Los Angeles River.
- June 6, 1987. The line broke near Lebec, dumping 8,400 gallons of oil into storm drains. The oil flowed about three-fourths of a mile, from the summit of the grade over the San Gabriel Mountains about three-fourths of a mile north to the Fort Tejon Campground.
- July 22, 1988. The line, weakened by corrosion, ruptured near Valencia. About 250 to 400 gallons of oil bubbled to the surface before the line was shut down.
- Aug. 6, 1988. Another corroded spot in the line gave way near Valencia. About 50 gallons of oil seeped to the surface.
- Sept. 10, 1988. The line ruptured in Encino, dumping 93,000 gallons. Corrosion, resulting at least in part from the proximity of an adjacent water pipeline, was blamed.
- Sept. 27, 1988. The line ruptured again, this time in Sherman Oaks, only a few hundred yards from the Encino break, while Mobil was conducting a pressure test, using water. About 120,000 gallons of a water/oil mixture--most of it water--emptied into the street and the Los Angeles River. Damage and contamination were considered relatively minimal. Officials said corrosion may have caused the weakness in the pipe wall that caused it to give way.
Mobil’s Salles said there are two principal methods used to protect the steel pipe from corrosion.
The first is a coating--usually some form of plastic--around the outside of the pipe to separate it physically from water and other compounds that can promote corrosion. The second is so-called “cathodic protection,” in which a low-voltage current is passed through the pipe to inhibit the corrosive process of electrolysis.
If both these methods are working properly, “the pipe should last forever,” Salles said.
But the pipe has not been lasting “forever.” Cathodic protection seems to have been breaking down. According to the National Transportation Safety Board, the tests performed annually under Department of Transportation regulations to determine if this breakdown is taking place are not working well.
Expert Opinions Differ
Dick Beam, director of the Department of Transportation’s office of pipeline safety, said there are differences of opinion among experts as to the best way to perform the tests.
“It’s like a couple of doctors who can’t agree on the best way to cure a patient,” he said.
Hernandez, chief of the fire marshal’s pipeline safety division, explained that cathodic protection is a relatively new field, many of the ramifications of which are not fully understood.
Of special concern, he said, is the interference caused by other adjacent underground lines--the sort of interference that may have caused the Sept. 10 break by neutralizing the cathodic protection system.
Salles said that in addition to the cathodic protection tests, pressure tests required by the state are made once every five years--using water instead of oil pumped to inflated pressures as high as 1,800 pounds per square inch. He said the tests are made every two years in the Los Angeles metropolitan area because of the population density. Two of the breaks in the Mobil line occurred during such testing.
In addition, Salles said, Mobil conducts a variety of tests on its own, including some in which an electronic sensing device is run through the pipe to check any minute variations in its thickness, which ranges from a quarter to half an inch.
Fire Marshal’s Responsibility
The office of the state fire marshal, which has the responsibility for implementing the federal regulations governing petroleum pipelines in California, checks the operation, maintenance and testing records of the pipeline operators and conducts a physical inspection of the exposed portions of the line. The checks and inspections are made about once every two years.
Mobil personnel also patrol the line on a regular basis, looking for signs of seepage along a route that, for the most part, dates back more than 70 years.
The Mobil line owes its origins to a former sea captain, John Barneson, who hauled American troops to the Orient during the Spanish-American War before starting up a shipping business in California.
Barneson is credited with being one of the first to think of using petroleum, rather than coal, to fuel ships. That led him to invest in oil leases, and that, in turn, led him to help found what was to become the General Petroleum Co., which eventually became part of what today is the Mobil Oil Corp.
Not long after the turn of the century, Barneson built what is believed to have been the world’s first long-distance oil pipeline to carry crude from the company’s fields near Coalinga to its docks in Monterey.
Second Major Line Built
In about 1916, construction began on a second major line to carry crude from the Lost Hills fields to the company’s new refinery near Vernon. Today’s line--essentially a modernization of the 1916 line--follows much the same route, although the southern terminus is the refinery built in the 1920s in Torrance.
The line, various sections of which have been replaced and upgraded over the years, begins at the Mobil fields on the bleak, western slope of the San Joaquin Valley near Lost Hills, about 15 miles northwest of Bakersfield.
Eight inches in diameter at Lost Hills, the pipe varies in diameter up to 16 inches on the long route south, depending on the amount of additional oil brought in from adjacent fields along the way and the grades over which the oil must be lifted. The highest point is a little over 4,400 feet, near Gorman, where the line crosses the Tejon Pass.
Nine electrically powered pumping stations along the way provide the impetus. The crude is heated to 180 degrees Fahrenheit at each of the stations to ease the pumping burden by reducing the oil’s viscosity.
The line crosses the California Aqueduct at several points. Check valves are positioned on either side of the aqueduct at these crossings to minimize spillage in the event of a break there.
6 Valves in 90 Miles
But there are only six more check valves spaced out over the last 90 miles of the route south, a paucity that has concerned some safety experts. This infrequent spacing means that even if the nearest valve is closed immediately, a break in some areas could cause as many as nine miles of pipeline to drain, spilling hundreds of thousands of gallons of crude oil.
“There have been proposals for one- to five-mile spacing, depending on the product,” Salles said. But the Department of Transportation conclusion is that the benefits just do not outweigh the expense, which could run into millions of dollars.
A National Academy of Sciences study released in September concluded that “because of the relatively good safety record of the industry, the benefits that can be obtained by improved pipeline safety do not warrant massive investment in new initiatives.”
The peculiar location of the Sept. 10 break, rather than any of the safety valves, was what limited the spill to 93,000 gallons, Salles said.
An alarm sounding at 4:08 p.m. alerted Mobil’s dispatch control center in Torrance that there had been a significant drop in pressure on the line somewhere north or south of the pumping station in the Saticoy area near Van Nuys Airport.
Pumping Stations Shut Down
After verifying the readings, the operator shut down the pump at Saticoy, the pumping station north of it at Newhall and the pumping station south of it at the Fox Hills Mall in Culver City. Oil heading south through the line was diverted into storage tanks in Newhall.
The line slopes downhill between the break and the Saticoy station so none of the oil north of the break drained out through the ruptured pipe. But the line runs uphill south of the break to the peak of the Sepulveda Pass over the Santa Monica Mountains. There are no check valves on the Sepulveda grade.
“The oil that drained out was from the crest of the grade back down to the break,” Salles said. “If we’d had a person standing there, there was nothing more we could have done.”