WRAL.com | Oil on Derailed Train in North Dakota Met State Rule, Hess Says Wall Street Journal Mr. Roper said the crude had been run through a “heater treater” to remove volatile gases and make the crude oil less combustible. He said the vapor pressure of the crude, a measure of its volatility, had been measured at the rail terminal in Tioga, N ... Oil in North Dakota derailment was treated to cut volatility Oil company: Shipment in North Dakota train derailment had been treated to ... |