Sarens transported two drive stations using self-propelled modular trailers (SPMT's) at one of the world's largest open pit copper mines near Salt Lake City, Utah. Each of the 286t drives travelled approximately 3 miles downhill on an 11% grade. A total of 18 axle lines of SPMT's were used in a 3 x 6 configuration with 2 power pack units (PPU) and a beam support structure.