The Nichols Ranch Project includes: (i) the Nichols Ranch Plant (100% ownership); (ii) the Nichols Ranch Wellfields (100% ownership); (iii) the Jane Dough Property (81% ownership); (iv) the Hank Project (100% ownership), which includes the permitted but not constructed Hank Satellite Plant; (v) North Rolling Pin (100% ownership); and (vi) West North Butte (100% ownership).
The Jane Dough Property contains certain properties that are 100% owned by Energy Fuels and other properties that are held in the Arkose Mining Venture. United Nuclear, owns a 19% interest in the Company’s Arkose Mining Venture while the Company owns the remaining 81%.
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Summary:
The Complex is located in the Powder River Basin, which is a large structural and topographic depression sub-parallel to the trend of the Rocky Mountains. The Basin is bounded on the south by the Hartville Uplift and the Laramie Range, on the east by the Black Hills, and on the west by the Big Horn Mountains and the Casper Arch. The Miles City Arch in southeastern Montana forms the northern boundary of the Basin.
The Powder River Basin is an asymmetrical syncline with its axis closely paralleling the western basin margin. During sedimentary deposition, the structural axis (the line of greatest material accumulation) shifted westward resulting in the Basin’s asymmetrical shape.
Uranium mineralization at the Complex deposits is hosted by the Eocene Wasatch Formation. The Wasatch Formation was deposited in a multi-channel fluvial and flood plain environment. The climate at the time of deposition was wet tropical to subtropical with medium stream and river sediment load depositing most medium grained materials. The source of the sediments, as evidenced by abundant feldspar grains in the sandstones, was the nearby Laramie and Granite Mountains.
Within the Complex, there is a repetitive transgressive/regressive sequence of sandstones separated by fine-grained horizons composed of siltstone, mudstone, carbonaceous shale, and poorly developed thin coal seams. The fine-grained materials were deposited in flood plain, shallow lake (lacustrine), and swamp environments. Ultimately, deposition of the Wasatch Formation was a function of stream bed load entering the basin and subsidence from within the basin. However, in the central part of the Powder River Basin, long periods of balanced stability occurred. During these periods the stream gradients were relatively low and allowed for development of broad (0.5 mi to 6.0 mi wide) meander belt systems, associated over-bank deposits, and finer grained materials in flood plains, swamps, and shallow bodies of water.
Meander belts in the Wasatch Formation are generally 5 ft to 30 ft thick. The A Sand at Nichols Ranch Area is made up of three to four stacked meander belts and the F Sand at Hank Area has two to three stacked meander belts. Individual meander belt layers will rarely terminate at the same location twice. Meanders have been noted to frequently terminate in the interior of a belt system but are more likely to terminate somewhere closer to the edge of the meander stream valley. The net effect for fluvial sands is to generally thin away from the main axis of the meander belt system. The A Sand meander belt system at Nichols Ranch Area is approximately four miles wide. At Hank, the F Sand meander belt system is smaller than Nichols Ranch at approximately one and a half miles wide.
At the North Rolling Pin Area, the mineralized sand horizon (F Sand) occurs within the Wasatch Formation at an approximate depth from surface ranging from 51 ft to 403 ft and averaging 282 ft to the top of the mineralization. Generally, the depth of mineralization decreases from the northeast to the southwest due mainly to topography along which the surface elevation decreases from approximately 5,180 ft to approximately 4,800 ft. The F Sand primarily consists of two stacked sand sets, termed the Upper and Lower F Sands that each average 20 ft to 25 ft thick.
The mineralized sand horizons occur within the lower part of the Wasatch Formation, at an approximate depth from surface ranging from 482 ft to 1,012 ft at West North Butte, 540 ft to 660 ft at East North Butte, and 172 ft to 567 ft at Willow Creek. The host sands are primarily arkosic in composition, friable, and contain trace carbonaceous material and organic debris. There are local sandy mudstone/siltstone intervals with the sandstones, and the sands may thicken or pinch-out in some locations. Mineral resources are located in the Eocene age Wasatch Formation in what is identified as the A, B, C and F host sand units of the WNB Area, the A and B host sands of the ENB Area and in the A and F host sand units of the WC Area.
The uranium mineralization is composed of amorphous uranium oxide, sooty pitchblende, and coffinite, and is deposited in void spaces between detrital sand grains and within minor authigenic clays. The host sandstone is composed of quartz, feldspar, accessory biotite and muscovite mica, and locally occurring carbon fragments. Grain size ranges from very fine to very coarse sand but is medium-grained overall. The sandstones are weakly to moderately cemented and friable. Pyrite and calcite are associated with the sands in the reduced facies. Hematite or limonite stain from pyrite are common oxidation products in the oxidized facies. Montmorillonite and kaolinite clays from oxidized feldspars are also present in the oxidized facies (Uranerz, 2010a). The uranium being extracted is hosted in a sandstone, roll front deposit at a depth ranging from 400 ft to 800 ft.
Wyoming uranium deposits are typically sandstone roll front uranium deposits as defined in the “World Distribution of Uranium Deposits (UDEPO) with Uranium Deposit Classification” (IAEA, 2009).