Kennecott Copper electric pit motors ramble slowly through the Bingham Canyon Copper Mine near Copperton, Utah. KCC 727 is an 85 ton, 1929 product of GE while KCC 762 is a 90 ton, 1942 product of GE. The 727 served at the open pit mine for 50 years until retirement in 1979 while the 762 served for 41 years until retirement in 1983. EMD GP39-2 diesels began to replace the unique GE electrics in the pit beginning in 1977. The very last rail ore haul from the mine took place on May 30, 2001. All ore extraction today is handled by trucks and is transported from mine to mill via an 18 mile concentrate slurry. The Bingham Canyon Copper Mine has been in production since 1906, and has resulted in the creation of a pit over 0.75 miles (1.2 km) deep, 2.5 miles (4 km) wide, and covering 1,900 acres (7.7 km²). According to Kennecott, it is the world's largest man-made excavation. It was designated a National Historic Landmark in 1966 under the name Bingham Canyon Open Pit Copper Mine.
