This group of Utah Ry. 6 axle units, led by an Australian built SD50, is rolling east on the ex. D&RGW main line through Helper, Utah. It is headed for the Castle Valley Spur a few miles further east where a loaded, 17,000 ton coal train is waiting. This set of engines will become the manned, mid train, helpers. All this horsepower is needed to lift the coal train up the 2.4% grade in Price River Canyon to Soldier Summit.