Diluted bitumen poses no special pipeline leak risks, NAS panel finds

July 8, 2013
Oil sands crude does not pose an increased risk compared with other crude oils when transported via pipeline, said a committee of scientists reporting to the US Department of Transportation.

Oil sands crude does not pose an increased risk compared with other crude oils when transported via pipeline, said a committee of scientists reporting to the US Department of Transportation.

The National Research Council said scientists determined that moving diluted bitumen (dilbit) through pipelines poses no special leak risks.

It also found no evidence of physical or chemical properties in dilbit that are outside the range of other crude oils, or any other aspect of its transportation by pipeline that would make diluted bitumen more likely than other crudes to cause releases, said NRC, which is part of the National Academies of Science.

American Petroleum Institute Pipeline Director Peter Lidiak welcomed the report.

"Canadian oil sands crudes have been transported safely in the US for more than 40 years," Lidiak said. "All crude oils have to meet the same criteria when put in a pipeline, which protects the pipeline and communities along its route, as well as the quality of all transported crudes."

The June 25 report came about a year after the committee heard from crude oil transportation experts that dilbit upgraded from Alberta's oil sands is essentially similar to other sour crudes (OGJ Online, July 24, 2012).

The June 25 findings were expected to dismay environmental organizations and other groups pressing the Obama administration to deny a cross-border permit to TransCanada Corp.'s proposed Keystone XL pipeline, which would carry dilbit from Alberta to US Gulf Coast refineries.

The conclusions likely pleased the project's supporters, which include the Canadian and Alberta governments, and numerous oil industry and other business associations on both sides of the border.

In the report's executive summary, NRC said it would have reviewed US federal pipeline safety regulations if it had found an increased likelihood of failures in pipelines transporting bitumen. Since it did not, it issued a final report documenting the study's approach and results.

In addition to the July 23, 2012, hearing, the committee also reviewed pipeline incident statistics and investigations; examined data on the chemical and physical properties of dilbit and other crude shipments; reviewed the technical literature; consulted experts in pipeline corrosion, cracking, and other causes of releases; and queried pipeline operators about their dilbit transportation experiences.

In accordance with the study's charge, the committee focused on whether dilbit shipments were likelier than other crudes to cause pipeline leaks, the report noted. It said it did not examine whether consequences from dilbit releases differ from other crudes, or if such a study is warranted.