A comprehensive third-party study released May 20 by the North Dakota Petroleum Council (NDPC) shows that Bakken crude oil is similar to other light crudes and meets all federal regulations and tank car design standards for shipping flammable liquids by rail.
“It is essential to separate fact from fiction as we work to enhance the safe transportation of crude oil,” said API president and CEO Jack Gerard. “Multiple studies have now debunked the idea that Bakken crude is meaningfully different than other crudes. This data will allow industry and regulators to base actions on science rather than speculation as part of our comprehensive approach to addressing concerns regarding the transportation of crude by rail, which includes prevention, mitigation and response.”
Independent third-party contractors performed the NDPC study by collecting and analyzing more than 150 samples of crude from wells and rail terminals in the Bakken shale region. Characteristics measured include API gravity, vapor pressure, initial boiling point, flash point and light ends content. Tested sample results were typical of light crude oil and classified as flammable liquids according to federal regulations. The study found no meaningful change in transit, little geographical variation and no evidence of corrosiveness.
These findings are consistent with test results from nearly 250 samples of crude oil that API members have already shared with the U.S. Department of Transportation.
The NDPC study found the test that the DOT requires for measuring crude oil’s initial boiling point can lead to varying packing group determinations for the same sample of crude. These limitations have no practical impact on the rail transport of Bakken crude oil because regulators authorize the same tank cars and emergency response methods for all crude oil and hydrocarbon transportation fuels.
A separate effort has found that vapor pressure alone is not a good indicator of crude oil flammability, according to the preliminary analysis by industry experts working with the DOT and Transport Canada. Both newer and legacy DOT-111 tank cars are designed to withstand vapor pressures of at least 100 psi, nearly 700 percent greater than the highest level measured in the NDPC study of 14.4 psi.
API continues to work with regulators and the railroad industry to develop a new standard for classifying, handling and transporting crude oil by rail. The working group developing it expects to have a draft standard in June. API’s standards are accredited by the American National Standards Institute, which accredits similar programs at U.S. national laboratories.