Heavy crude oil to be carried by the proposed Keystone XL pipeline poses no greater risk of a spill than other types of oil, the National Research Council said in a report.
The report disputes arguments made by Keystone opponents that diluted bitumen, a tar-like substance mined in Alberta’s oil sands, is more corrosive than conventional crude oil and is more likely to create ruptures and oil spills in pipelines.
“There have been several studies to look at this over the years, but none that have been as credible and comprehensive as the NAS study,” Greg Stringham, vice president of markets and oil sands for the Canadian Association of Petroleum Producers, said in a telephone interview from Calgary. “It does provide a very definitive conclusion.”
The study may also bolster the case for other pipelines to carry oil derived from Canadian tar sands, he said.
The review of spills “did not find any causes of pipeline failure unique to the transport of diluted bitumen,” according to a statement from the council, part of the National Academy of Sciences that advises the U.S. government on science policy.
“There’s nothing extraordinary about pipeline shipments of diluted bitumen to make them more likely than other crude oils to cause releases,” Mark Barteau, a chemical engineering professor at the University of Michigan, said in a statement accompanying the report released today. Barteau was the chairman of the committee that wrote the report.
The State Department is reviewing TransCanada Corp.’s (TRP) application to build the $5.3 billion link between Alberta and Steele City, Nebraska, where the pipeline would link to a project under construction to carry the oil to refineries in the U.S. Gulf Coast. A decision is possible later this year.
The Pipeline and Hazardous Material Safety Administration, a part of the U.S. Transportation Department, requested the council’s report. Congress directed the department to study transporting diluted bitumen in a 2012 pipeline safety law.
“Dilbit” has been transported in the U.S. for 30 years, according to the report. The U.S. has about 55,000 miles (88,500 kilometers) of oil transmission lines. Pipeline spills ranged from 80 to 120 a year from 2002 to 2011, according to the study. Any spill releasing 5 gallons or more is reported.
The Keystone proposal, along with spills such as Enbridge Inc.’s Michigan rupture in July 2010 and a more recent incident on an Exxon Mobil Corp. (XOM:US) line in Mayflower, Arkansas, have led environmental groups like the Natural Resources Defense Council to oppose shipping bitumen by pipeline because they say doing so carries greater risk.
A February 2011 report by the New York City-based NRDC said said spills were more likely because bitumen is acidic and moves through pipelines at higher temperatures than other oils, increasing the risk of corrosion. The National Academy of Sciences report contradicts the NRDC’s research.
Anthony Swift, an NRDC lawyer and an author of the report, said questions remain about higher risks from external corrosion at higher temperatures, as suggested in a 1993 study of California pipelines carrying heavy crudes. Bitumen also may inflict more damage on the environment, especially in waterways, from a spill, he said.
“It does answer some questions, there’s no question about that, and I’m not criticizing the work that the National Academy of Sciences did, but I am commenting on the the very limited scope of the study,” Swift said in a telephone interview from Washington.
Oil and gas pipelines today reach temperatures of about 120 degrees Fahrenheit (49 degrees Celsius), “which is about the temperature of the hot water lines in your house,” Barteau said in a press conference today.
The council found the 1993 California study wasn’t “directly applicable” to today’s pipelines, which have modern coatings and protection from corrosion, Barteau said.
The bitumen is diluted with lighter oils to lower its viscosity in the pipeline.
The alleged corrosive properties of bitumen is one argument made by opponents of Keystone. Environmental groups including the San Francisco-based Sierra Club also argue the pipeline will encourage development of the oil sands.
Oil sands release 8 percent to 37 percent more greenhouse gases during production and use than conventional oil, according to the Pembina Institute, a Calgary-based non-profit research and advocacy group.
Oil sands production is forecast to more than double to 5.2 million barrels a day by 2030 from 1.8 million currently, the Canadian Association of Petroleum Producers said in its annual forecast released June 5.
Canada is increasingly reliant on revenue from oil. Energy products were the nation’s fastest-growing export over the past 20 years, increasing to 23 percent of all shipments, from 9 percent in 1993, according to Statistics Canada.
The State Department’s draft environmental analysis said Keystone won’t increase climate-change risks because the oil sands will be developed even without the project. The Environmental Protection Agency criticized the draft analysis, and asked the state Department to conduct a fuller review.
Critics also say that, once spilled, bitumen is tougher to remove. Unlike conventional crude, bitumen sinks in water rather than floating on the surface where it can be skimmed off.
In October, the EPA said Enbridge must do more to clean a spill in Michigan’s Kalamazoo River from a pipeline rupture.
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