Another was the railroad's use of EMD F7 locomotives, often in A-B-B-B-B-A configurations, painted in U.S. Steel's own yellow and black livery.
The railroad's genesis was in the construction of the Geneva Steel mill in Vineyard, Utah during World War II.
The federal government backed the construction of the steel mill for national security purposes, reasoning that its location far inland protected it from any Japanese attack on the West Coast.
Initially, Geneva Steel Works drew its raw materials from an iron ore mine at Cedar City, Utah.
[1] That mine proved insufficient to keep Geneva Steel Works operating at full capacity, so U.S. Steel sought a secondary source of iron ore. Owing at least in part to a geological report issued jointly by the Geological Survey of Wyoming and the University of Wyoming Natural Resources Research Institute in 1949,[2] U.S. Steel became aware of a large reserve in the Wind River Mountains in Wyoming, north of Atlantic City and south of Lander.
[7] The line began at a connection with the Union Pacific at Winton Junction, north of Rock Springs, and extended north and then northeast, snaking past the west side of South Pass City and then turning northeast before concluding at the mine.
[8] Below South Pass, civil engineers encountered a peat bog across the route, which was unusual for such an arid climate.
At the mine, U.S. Steel extracted a hard, slate-like rock called magnetic taconite, which was only about 30 percent iron.
712B, 723A and 724A all later became property of the Washington Central Railroad, while 726A fell into the hands of Passenger & Freight Locomotive in San Antonio.
[1] On numerous occasions over the years, the idea of reopening the Atlantic City Iron Ore Mine has been studied, given worldwide steel demand.
[13] Reopening of the mine, whose mineral rights are owned by the J.R. Simplot Company, would entail building a new rail line to transport the ore.[13]