U.S. Senator Heidi Heitkamp (D-N.D.) has introduced legislation to require freight trains carrying cargo like crude oil to operate with at least two crewmembers on board, her office announced Thursday.

In a statement, Heitkamp noted that the presence of two crew members aboard a crude rail train that derailed in Casselton, North Dakota in 2013, prevented a resulting fire from growing.

“When a disaster like the Casselton derailment sends shockwaves through our communities, we must do everything we can to prevent accidents and improve our ability to re...