Cristobal Sustaita didn’t know about the pipeline running underground near his West Texas home until it erupted into a fireball in 1976, burning to death five people including his wife and 20-month old son.
The explosion was one of the first to focus attention on a lethal welding flaw in U.S. pipelines built before 1970. In the decades since, this type of pipe has continued to leak, rupture and explode, killing more people, despite repeated warnings to the industry from federal investigators and private consultants.
In fact, as much as 50,100 miles of similar pipelines — a quarter of all U.S. liquid-bearing lines — still crisscross communities carrying explosive products such as gasoline, liquefied gas or crude oil. While critics contend their lingering presence represents an unacceptable public safety threat, pipeline industry officials estimate it would cost $50 billion to replace them all, helping explain why they remain.
The U.S. Transportation Department, which has oversight through its Pipeline Safety and Hazardous Materials Administration, is required to weigh costs against the fact that the number of accidents involving welded pipe are a small percentage of all pipeline accidents. Phillips 66 and Magellan Midstream Partners LP are among pipeline operators that might have to pay for upgrades if they were ordered.
“There isn’t a silver bullet,” said Carl Weimer, executive director of the Pipeline Safety Trust, a non-profit watchdog. “It’s going to be a hard fix and with 50,000 miles of it in the ground, it’s going to be an expensive fix.”
Meanwhile, they continue to rupture. The latest major incident — an Exxon Mobil Corp. oil spill in March that swamped an Arkansas neighborhood — may provide the final push to action for Washington regulators studying whether more needs to be done to prevent future accidents. They’re considering whether to mandate new, more expensive tests, or even force companies to dig up the pipes to look for corrosion, according to Weimer.
“I think that’s the noose that’s tightening,” Weimer said in an interview from Bellingham, Washington.
The Whitharral, Texas, explosion is among at least 200 accidents that have occurred along the same kind of welded pipe, bringing total deaths blamed on the defect to at least 14, according to data gathered by pipeline safety administration.
In 1976, National Transportation Safety Board investigators had quickly realized the Texas disaster pointed to a bigger problem. The 8-inch pipe carrying liquefied petroleum gas had cracked open along a welded seam — a defect they’d begun seeing more frequently in pipelines failures.
Vapors poured from the rupture, building into a cloud that eventually ignited. The explosion shot flames 200 feet into the sky and engulfed an area nearly a mile long and a quarter mile wide, including Sustaita’s home while he was away visiting his parents. Both his baby son and wife lingered a few days in the hospital before dying.
Sustaita, who was 33 when he lost his family, moved to Michigan to get out of the oil patch and away from the oil rigs and pipelines that reminded him of the accident, he said in an interview. But 37 years later, he still hasn’t lost his fear of pipelines. “I don’t want to be near them at all,” he said.
While the U.S. debates the safety of proposed new pipelines such as the Keystone XL from Canada — deemed by owner TransCanada Corp. to be the safest, most modern pipeline ever designed — more than half the nation’s pipelines are at least 40 years old. They were built before current standards such as corrosion protection and X-ray testing were in place. Policing old pipe that’s at higher risk for ruptures has become one of the biggest challenges of U.S. transportation officials.
Demand for pipeline capacity in the U.S. has skyrocketed as improved drilling methods unlocked huge new sources of oil and natural gas that need to be moved to market. Pipeline companies, seeking the fastest, cheapest way to increase capacity, have repurposed many of their older pipes to carry different kinds of products.
Faulty welds and materials accounted for 36 percent of spills and leaks on liquids pipelines between 2006 and 2010, more than any other cause, according to a Transportation Department report. Low-frequency electric resistance welded pipe, or ERW, such as that used at Whitharral, was identified as prone to seam failures as early as the 1960s. In use since the 1930s, it was phased out by 1970 and replaced by stronger welding techniques.
Over the decades, federal pipeline safety regulators now known by the acronym PHMSA have relied on company testing programs to detect flaws in pipelines before they get bad enough to cause a rupture or leak. Line operators use devices known as “pigs” to run through the pipes taking measurements with sonar and magnetic waves to find cracks, dents and corrosion. The pigs are used to supplement more expensive and infrequent tests, such as filling the pipe with pressurized water to test for leaks.
Between 2000 and 2005, the agency required more rigorous testing of pipes in populated or environmentally sensitive areas, and asked companies to avoid increasing pressure on older ERW pipes. Now, it’s focusing on whether those tests are adequate to prevent accidents with the ERW pipe.
“Operators don’t fully understand the limitations of the tools,” said Alan Mayberry, a deputy associate administrator at the safety agency. In 2011, it began a study of pipe testing procedures, with results of the study due next year.
Replacing all the ERW pipe still in use would cost as much as $1 million a mile, or more than $50 billion, said Brigham McCown, a Dallas transportation consultant who served as administrator of PHMSA in 2005 and 2006. About half of the pre-1970 ERW pipes are owned by five companies, according to 2012 data from the Transportation Department.
Phillips 66, the pipeline operator spun off by ConocoPhillips, has about 5,300 miles. Magellan Midstream, which ships gasoline and other refined fuels, has about 5,000 miles. Enterprise Products Partners LP, the nation’s second-biggest pipeline company, is third with about 4,300 miles. Buckeye Partners LP, which transports oil, jet fuel and other products, owns 4,000 miles. Exxon, the biggest U.S. oil and gas producer, owns about 3,500 miles.
Exxon and Phillips 66 said in statements that they have special procedures to monitor ERW pipe and stressed their commitment to safety.
“The age of the pipe steel alone cannot be used to determine a pipeline’s integrity,” Aaron Stryk, an Exxon spokesman, said in a statement. Magellan complies with all federal rules, Bruce Heine, a spokesman, said in an e-mail, without further comment. Buckeye and Enterprise declined to comment, representatives for the companies said in interviews.
The Association of Oil Pipe Lines, a trade group, says companies should have the freedom to spend their maintenance dollars on the most pressing problems, rather than being forced to focus on older pipelines.
“There are no inherent safety concerns to pipe that’s well-maintained,” John Stoody, a spokesman for the association, said in an interview.
Overall, pipeline safety is improving, according to PHMSA. Annual injuries and deaths from pipeline accidents fell by more than half in 2009 from 1991, the agency says on its website. It issued a record $8.75 million in fines in 2012.
Typically, ERW was formed from a flat sheet of metal rolled into a tube, according to a 2002 report by the engineering firm Kiefner & Associates Inc. The pipe’s seam was sealed by heating the edges with electric current and forcing them together under pressure. Companies installed more than 18,000 miles of ERW pipeline in the 1950s and 19,000 miles in the 1960s, according to Transportation Department data.
The technology allowed fast and cheap expansion of the nation’s energy transportation network, said Bob Fassett, a pipeline expert at the Santa Rosa, California, consulting firm Kleinfelder. Later it was discovered the method left a brittle area in the pipe along the welded seam, which was prone to corrosion and cracking, Fassett said.
Federal investigators documented 14 previous seam failures since 1968 along the same pipe system that exploded in Texas. Five other people had been killed in those incidents and 2.5 million gallons of fuel spilled, according to Transportation Department data and a June 14, 1976, report by the transportation safety board, known as NTSB. The investigators issued a warning to the Transportation Department urging the agency to review all similar pipelines for the same kind of defect and to “take necessary corrective action.”
The Transportation Department responded at the time that flawed welds led to only a small percentage of pipeline incidents and declined to take action, according to a 1986 Transportation Safety Board review of the Whitharral explosion and several later incidents.
Ten years after the Whitharral disaster, two people died in a fire after the same kind of seam ruptured on a gasoline pipeline in Mounds View, Minnesota. The safety board recommended that the Transportation Department determine if electric-resistance welded pipe “presents an unreasonable hazard,” according to an investigator’s report on the accident.
In 2007, another two died in an explosion in Carmichael, Mississippi, after a 52-foot section of a pipe split along its seam, according to an NTSB report. Investigators identified a ruptured ERW seam as the culprit when they issued their final report two years later, and recommended for the third time that pipeline safety regulators study the problems connected to ERW pipe.
Investigators observed that operators had tested their pipe within a year or two of many of the accidents. Enterprise Products Partners, the majority owner of the Mississippi pipe that exploded, had tested its line twice in the two years before it ruptured without finding a significant flaw in the section that ruptured, according to the NTSB.
“Current inspection and testing programs are not sufficiently reliable” to find problems in ERW pipe, the NTSB concluded in its report on the incident.
It was not the first time researchers had come to that conclusion. In 1988, Shell Pipe Line Corp.’s Ozark line, which was made with ERW pipe, ruptured and dumped 20,000 barrels of oil into the Missouri River, according to Transportation Department records.
Around that time, U.S. Senators Chris Bond and John Danforth of Missouri asked the National Institute of Standards and Technology, a technology lab run by the U.S. Commerce Department, to review the history of ERW pipe.
“It is clear that ERW pipe manufactured before about 1970 is particularly susceptible to failure,” the institute said in a 1989 report. It documented 172 seam failures in ERW pipelines carrying liquids over the previous 20 years. The research reported evidence that corrosion and metal fatigue caused by pressure changes from flowing liquids could worsen the pipe’s weld defects.
Researchers recommended extra testing for ERW pipe and precautions such as installing cutoff valves to protect river crossings and populated areas. They also suggested companies consider replacing some of the pipe in sensitive areas.
The Transportation Department advised pipeline companies in 1988 and 1989 to monitor ERW pipe more closely for corrosion and to either reduce the lines’ operating pressure or retest them to ensure they’re operating within safe limits.
Previous tests of Exxon’s Pegasus pipeline that spilled 5,000 barrels of oil in Mayflower, Arkansas, earlier this year had discovered no problems, according to a May 10 PHMSA report. Conclusions drawn from another test just weeks prior to the rupture are not yet available. In a July statement, Exxon blamed the seam split on a “manufacturing defect,” after a study the company commissioned found small cracks that had worsened over time.
In 2011 the Transportation Department began a $4.2 million study of ERW pipe failures and the adequacy of industry tests and possible alternatives. The study followed two high-profile pipeline disasters in 2010: a natural gas pipeline that exploded in San Bruno, California, killing eight people, and an Enbridge Inc. pipeline rupture that spilled 20,000 barrels of crude into a creek that feeds the Kalamazoo River outside Marshall, Michigan. Neither of the 2010 incidents involved ERW seam ruptures, but both involved pipes older than 40 years.
The independent labs running the PHMSA study have produced preliminary reports confirming that inline “pigs” can’t always detect problems in older ERW pipe, and recommending a combination of pressure-testing and inline testing.
PHMSA is considering tougher standards for testing and monitoring pipelines. One approach may be to require companies to excavate pipes and visually verify the cracks and dents spotted by inline pigs, to determine if the pigs are accurately identifying problems, PHMSA’s Mayberry said in an interview.
Mandating a replacement program for ERW pipe in populated areas “is a no-brainer,” said James Hall, a former chairman of the National Transportation Safety Board. “The record of the pre-1970-ERW pipe speaks for itself and I think the risk justifies the replacement cost.”
“It doesn’t make economic sense for the future of our country that we don’t address a lot of this older pipe that’s in the ground now,” Hall said.