Train car corrosion may increase risk of oil spills

The growth in the use of hydraulic fracking has led to an oil production boom in the U.S, and much of this commodity has been moved by rail.

According to the Association of American Railroads, Class 1 railroads moved 9,500 carloads of crude oil in 2008. By 2012, that amount reached 234,000 carloads. And as of May 2013, 97,000 carloads of oil were moved, meaning that the total is set to increase once again.

In many ways, rail transportation is considered a superior way to move oil when compared to pipelines. The U.S. Department of Transportation estimates that the spill rate for railroads between 2002-2012 was only 2.2 gallons per million ton-miles. For pipelines, the spill rate was 6.3 gallons per million ton-miles.

However, some regulators are worried that this rate will begin to rise as a result of some of the chemicals used in hydraulic fracking. According to an article in Bloomberg Businessweek, the U.S. Federal Railroad Administration is currently investigating some of these chemicals to determine whether they cause rail tank cars to corrode. 

An investigation was spurred by the July 6 train explosion in Quebec that killed 47 people. Crude oil doesn't normally explode, which is why fracking chemicals have come under suspicion. The oil in question was pumped from North Dakota's Bakken shale.

"Crude historically has not been considered in the highest category of hazmat," said independent analyst Anthony Hatch. "The risks have been considered to be environmental, not to humans. Perhaps Bakken crude should be considered in a higher category."

In order to avoid future disasters, manufacturers must learn what they can from these investigations and conduct cyclic corrosion testing to ensure that rail cars will not corrode when transporting oil.