The National Transportation Safety Board is still investigating the the train derailment and explosion in Casselton, North Dakota. A train carrying crude oil from the Bakken Shale in North Dakota derailed and exploded outside the city limits.
But an investigation into the safety of shipping crude oil from the Bakken Shale has been ongoing since this summer.
The crude oil that is extracted from the Bakken Shale through the process of hydraulic fracturing has raised concerns that the chemicals used in the process make the crude oil explosive and corrodes rail tank cars.
These concerns have led the Federal Railroad Administration and the Pipeline and Hazardous Materials Safety Administration to conduct spot inspections of the oil called the Bakken Blitz.
The investigation may lead to a re-classification of Bakken crude as a more hazardous substance than crude oil that is extracted from other locations.
Angela Greiling Keane, a reporter for Bloomberg News, joins Here & Now’s Meghna Chakrabarti to discuss the ongoing investigation.