Groups urge oversight of tar sands pipelines
As the U.S. State Dept. considers a proposal to build a nearly 2,000-mile long pipeline to transport Canadian tar sands to refineries on the Gulf Coast, key
Jul 31, 2020137.6K Shares2.3M Views
As the U.S. State Dept. considers a proposal to build a nearly 2,000-mile long pipeline to transport Canadian tar sands to refineries on the Gulf Coast, key questions about the safety of moving tar sands by pipeline remain unanswered, watchdog groups warned this week.
Alberta tar sand is a low grade asphalt-like petroleum product, also known as bitumen, that is strip-mined or melted out of the ground and requires elaborate processing in order to be used as fuel.
Previously tar sands oil was refined in Canada and was transported via pipeline for use in the U.S. Now, with Canadian refineries at capacity, the gooey raw tar sands is mixed with lighter chemicals (natural gas condensate) to make it thin enough to pump and sent to the Midwest for refining via those same pipelines.
In a report(PDF) presented this week, the National Resources Defense Council, Pipeline Safety Trust and Sierra Club warned that diluted bitumen, or DilBit, is more acidic and has more abrasive quartz sand particles, dramatically increasing corrosion dangers on pipelines.
“Without much public knowledge or a change in safety standards,” the report states, “ U.S. pipelines are carrying increasing amounts of the corrosive raw form of tar sands oil. In fact, over the last ten years, DilBit exports to the United States have increased almost fivefold, to 550,000 barrels per day (bpd) in 2010.”
The report compares spill data for the U.S. and Canadian pipeline systems and finds that the Alberta liquid pipeline system, which handles more DilBit, has experienced 16 times as many spills caused by internal corrosion.
Pressure changes within pipelines can cause the natural gas liquids in DilBit to move from liquid to gas, forming a bubble that can slow the flow of oil through the line, the report states. This phenomenon — column separation — can look like a leak to pipeline monitors and can cause real leaks to go unnoticed.
“Because the proper response to column separation is to pump more oil through the pipeline, misdiagnoses can be devastating,” the report asserts.
Initial National Transportation Safety Board review of the Enbridge pipeline rupture that spilled an estimated million gallons of DiBit into the Kalamazoo River watershed in Michigan last summer indicatesthat confusion over apparent column separation may be a partial explanation for why it took operators more than half a day to respond to that leak.
The economic and environmental costs of cleaning up a DilBit spill can be more severe than in conventional oil spills, the report states.
“„[U]nlike conventional crude oils, the majority of DilBit is composed of raw bitumen which is heavier than water. Following a release, the heavier fractions of DilBit will sink into the water column and wetland sediments. In these cases, the cleanup of a DilBit spill may require significantly more dredging than a conventional oil spill. Further, heavy oil exposed to sunlight tends to form a dense, sticky substance that is difficult to remove from rock and sediments. Removing this tarry substance from
river sediment and shores requires more aggressive cleanup operations than required by conventional oil spills.
The report authors note that the DilBit spill from the Enbridge pipeline in Michigan is not yet cleaned up, in part because submerged oil remains a problemin the Kalamazoo River.
These cleanup difficulties, now playing out in Michigan, were forecast by the U.S. Environmental Protection Agency last summer in a [letter](http://yosemite.epa.gov/oeca/webeis.nsf/(PDFView)/20100126/$file/20100126.PDF) (PDF) asking for more study on tar sands pipeline safety.
EPA warned that diluted bitumen may not behave like conventional oil in a spill and may be more difficult to clean up with “floating oil” spill response equipment and other traditional measures.
Concern about the environmental risks of tar sands pipelines is running high in Nebraska where TransCanada’s propose Keystone XL pipeline would cross the Ogallala aquifer — source of drinking water for million and the ‘life blood of agriculture.’
Ken Winston of the Nebraska Sierra Club said that TransCanada is acting like a used car salesman trying to close a deal before the prospective buyer realizes the defects in a vehicle.
“This report is like a warning light going off in that vehicle,” he said.
Information about the dangerous properties of tar sands oil is all the more troubling in view of statements by TransCanada on how it will supervise its planned line, Winston said.
At a Natural Resources Commission hearing(PDF) in the Nebraska Legislature in December, TransCanada Corporation vice president Robert Jones acknowledged that the company’s automated monitoring systems would not detect all leaks.
“I can tell you that we will be able to find small leaks in what we consider to be in that 1 to 2 percent range,“ he said. “… If there’s a thousand barrels that doesn’t add up every minute, then the computer is going to start trying to figure out where that may be.”
Jones said that TransCanada plans to rely on adjacent landowners to inform company about leaks below that threshold.
“Sounds pretty good,” Winston said, “but when they are talking about 880,000 barrels a day one percent would be almost 9,000 barrels. A barrel is 55 gallons. We are talking potentially 40,000-50,000 gallons could be undetected — a rather significant amount.”
The Natural Resource Defense Council, Pipeline Safety Trust and Sierra Club are calling on the U.S. Dept. of Transportation and pipeline operators to evaluate the need for new standards for tar sands pipeline and improved spill response planning and they say that the Keystone XL pipeline approval process should be put on hold until the U.S. has stronger safety regulations for DilBit pipelines.
Pipeline Transportation Safety Improvement Act of 2011introduced by Sen. Frank Lautenberg (R-N.J.) would require research into the pipeline safety issues posed by DilBit and overhaul of the nation’s pipeline safety system.
This bill was also introduced last year and died in committee.
Rhyley Carney
Reviewer
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