Uranium mining in Wyoming

[3] US Geological Survey geologist David Love discovered uranium in 1951 near Pumpkin Buttes, about 25 miles northeast of Midwest, Wyoming.

[5] Uranium was discovered in 1952 in Cretaceous sandstones of the Inyan Kara Group near its outcrop in Crook County, Wyoming, near the northeast edge of the Black Hills.

[1] The Gas Hills district, straddling the Natrona-Fremont county line in central Wyoming, was discovered on 9 Sept. 1953 by Neil McNeice, which led to the development of the Luck Mc Mine and others, with ore production beginning in 1955.

The ore consisted of lenticular bodies of meta-autunite, uraninite, and coffinite in fluvial arkosic sandstones in the upper Wind River Formation of Eocene age.

The ore occurs as roll fronts in Eocene sandstone of the Wind River Formation, as uraninite with pyrite, marcasite, hematite, calcite, and organic matter.

[10] The Crooks Gap district of Fremont County contains uranium ore in fluvial sandstones of the Eocene Battle Spring Formation.

[8] By 2006, the only active uranium mine in Wyoming was the Smith Ranch-Highland in-situ leaching operation in the Powder River Basin, owned by Power Resources, Inc., a subsidiary of Cameco.

[12] In October 2007, Energy Metals Corp. applied for a Nuclear Regulatory Commission (NRC) permit to start an in-situ leach mine at the Moore Ranch deposit in Campbell County in the Powder River Basin.

Wyoming uranium production.
Geologic map of the Pumpkin Buttes uranium area
Map of the Shirley Basin Uranium Area.
Map of the Crooks Gap-Green Mountain and Great Divide Basin Uranium Areas. Large yellow stars depict past producers and smaller yellow stars depict prospects.