"On the evening of December 1, 2010, Chevron Pipe Line Company's (CPL) controller shut down their Number 2 pipeline that delivers crude oil to their Salt Lake City (SLC) refinery. The pipeline transports crude oil from Rangely, Colorado to the SLC refinery via the Hanna pump station. After the Hanna station, the pipeline crosses Wolf Creek Pass and quickly descends into the Salt Lake Basin, traversing the eastern slope of Salt Lake City. The line was shut down because of some erratic supervisory control and data acquisition (SCADA) information following restart of the line after a planned shutdown."
Pipeline and Hazardous Materials Safety Administration: http://phmsa.dot.gov/