Activist opponents of the Keystone XL pipeline that would transport nearly 1 million barrels of diluted bitumen derived from Canadian oil sands claim that it would be more prone to leak than other pipelines. As Friends of the Earth (FOE) asserts:
The probability of spills from this pipeline is high and more threatening than conventional spills…. Experts warn that the more acidic and corrosive consistency of the type of tar sands oil being piped into the U.S. as well as the risk of external corrosion from higher pipeline temperatures makes spills more likely, and have joined the EPA in calling on the State Department to conduct a thorough study of these risks.
Well, a more thorough study of the risks has now been completed by an expert panel assembled by the National Research Council (NRC) and it finds that FOE's claims are false. From the NRC press release:
Diluted bitumen has no greater likelihood of accidental pipeline release than other crude oils, says a new report from the National Research Council. The committee that wrote the report found that diluted bitumen has physical and chemical properties within the range of other crude oils and that no aspect of its transportation by pipeline would make it more likely than other crude oils to cause an accidental release….
The committee did not find any causes of pipeline failure unique to the transport of diluted bitumen. In addition, it found no physical or chemical properties outside the range of other crude oils and no evidence that pipeline operators manage or maintain their systems any differently when transporting diluted bitumen compared with other heavy crude oils.
"Diluted bitumen has density and viscosity ranges that are comparable with those of other crude oils," said Mark Barteau, professor of chemical engineering at the University of Michigan and chair of the committee that wrote the report. "It moves through pipelines in a manner similar to other crude oils with respect to flow rate, pressure, and operating temperature. There's nothing extraordinary about pipeline shipments of diluted bitumen to make them more likely than other crude oils to cause releases."
The report also says that shipments of diluted bitumen do not contain higher concentrations of water, sediment, dissolved gases, or other agents that cause or exacerbate internal corrosion, including microbiologically influenced corrosion, and the organic acids in diluted bitumen are not corrosive to steel at pipeline operating temperatures. In addition, the committee found no properties in diluted bitumen that could make transmission pipelines more vulnerable to erosion, external corrosion and cracking, or damage from mechanical forces.
This new NRC report should make President Barack Obama and the State Department feel a bit more comfortable about approving the construction of the Keystone XL pipeline. That's assuming that the Obama administration has any intention of basing its decisions on science rather than politics.