A study conducted by Hurst Metallurgical Research Laboratory, funded by Exxon Mobil Corp., found that the Pegasus pipeline ruptured due to original manufacturing defects that only deteriorated over time, according to Bloomberg. The Pegasus pipeline is about 850 miles long, running from Illinois to Texas, and transports approximately 95,000 barrels of oil per day. On March 29, the pipeline leaked about 5,000 barrels of oil in Mayflower, Arkansas. The seam where the leak occurred was “electric resistance-welded.” Defects in pipelines built before the 1970s with this type of seam are common. The Pegasus line was built in the 1940s.
With the U.S. energy boom, the pipeline infrastructure has come under the spotlight. And what the spotlight has revealed is that the aging system cannot handle the volume of oil currently pumping through the pipes. When the system cracks, leaks and spills occur. To prevent this waste of precious resources and the subsequent environmental havoc, new pipeline infrastructure, coupled with careful maintenance and monitoring of the old lines, is necessary.
As of 2011, about 300,000 miles of pipeline stretch across the U.S. to transport oil, according to a U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration report. About 55% of the system was constructed before 1970, but it wasn’t until 1968 that the federal government put the first pipeline safety regulations in place.
There are tens of thousand of miles of pipelines built with similarly questionable techniques. These lines must be identified and replaced.
Between 1993 and 2012, 23.1% of onshore hazardous liquid pipeline reported incidents resulted from corrosion, while about 40% resulted from material, welding, or equipment failure, according to PHMSA Reported Pipeline Incidents. Hazardous liquid pipelines are those that transport all oil products. An incident is defined as any failure in the pipeline infrastructure that either results in the release of the liquids or carbon dioxide into the ecosystem or in injury or death.
This means that over half of the reported incidents are attributable to failures in identifying defective infrastructure. Of course, building new pipelines takes time, so it is unrealistic and inefficient to expect complete and immediate replacement of the old or defective infrastructure. This is where effective monitoring comes in. Operators of the infrastructure must keep vigilant watch and identify suspect lines.
There are, of course, alternatives to pipeline transport; the primary one is rail, and since the beginning of the U.S. unconventional energy boom, there already has been a huge jump in rail transport of oil. According to the Association of American Railroads, 355,933 cars carrying petroleum products moved by rail in 2013 as of June 29. This reflects a 47.9% increase from the same time period in 2012.
Meanwhile, railroad incidents involving crude oil jumped significantly over the last two years. There were 88 reported incidents in 2012, up almost 900% from 2010. Most of these incidents occurred because of valve and vent leaks, according to EnergyWire.
Some might argue that, similarly, pipelines suffer from the same troubles. If a seam or a crack appears, the oil would leak. But trains also have to deal with accidents. In late March, an oil-carrying train derailed in Minnesota, spilling about 30,000 gallons. Then on July 6, an unmanned train derailed in Lac-Megantic in Quebec, killing 47 people and spilling 72 cars worth of Bakken crude into the town’s lake, according to Reuters.
In 2012, there were 361 reported hazardous liquid pipeline incidents versus the 88 train incidents. Rail moves about 255 million barrels of oil per year, according to the U.S. Energy Information Administration, versus the 11.3 billion barrels annually delivered by pipelines, according to the Association of Pipelines. If we look at incidents per barrel, pipelines are much safer. This is not even accounting for the fact that hazardous liquid also includes other products, such as ammonia, so the figure 361 is inflated.
Currently, there is no perfect solution, but pipeline infrastructure regulations have evolved quickly, as expectations for monitoring and maintaining the system have become increasingly sophisticated. Pipeline infrastructure is both more efficient and, when properly maintained, more reliable and longer lasting than rail transport. New lines will relieve the pressures of increased domestic oil production, while proper upkeep will minimize incidents.