In the Pumpkin Buttes Uranium District, which includes the Reno Creek, Moore, Bing, and Pine Tree deposits, important economic uranium deposits occur in medium to coarse-grained greywacke sand facies in the lower portion of the Eocene Wasatch Formation. The sandstone host rock is composed of poorly sorted, angular grains of quartz, feldspar and rock fragments ranging in size from 0.063 to 2.0 millimeters. Found between these grains is a finer-grained matrix or interstitial material consisting of silt, clay and some organic material. When mineralized, very fine-grained particles of uranium minerals occur scattered throughout the interstitial matrix. As described in Section 13, the permeability in the mineralized sandstone generally is above 1 Darcy (1000 md) across the project area. The uranium mineralization occurs along roll front trends formed at geochemical reduction-oxidation (redox) boundaries within the host sandstone aquifers. Roll front uranium minerals in the unoxidized zone are commonly coffinite and pitchblende (a variety of uraninite). Low concentrations of vanadium (less than 100 ppm) are sometimes associated with the uranium deposits.

Uranium deposits accumulated along roll-fronts at the down-gradient terminations of oxidation tongues within the host sandstones. The deposits occur within sandstones, which are intermittently interbedded with lenses of siltstone and claystone, commonly referred to as mudstones at the project due to the mixture of partic ........

AUC plans to mine the uranium using the ISR method. For purposes of operations, the North and Southwest Reno Creek Resource Units will be unitized into a single operation called the Reno Creek Resource Unit. Mining of the reserves will occur in the Reno Creek Unit and the Moore and Bing Units.

The basic requirement for ISR mining is that mineralization is located in water-saturated permeable sandstone bodies that allow effective confinement of mining solutions, typically confined between impermeable clay-rich strata.

Wellfields are the groups of wells, installed and completed in the mineralized zones that are sized to effectively target delineated ore and reach the desired production goals. One header house controls the operation of each wellfield. The ore zones are located within the geologic sandstone units where the leaching solutions are injected and recovered via wells in an ISR wellfield and it is bounded between aquitards.

The proposed uranium ISR process will involve the dissolution of the water-soluble uranium compound from the mineralized host sands at near neutral pH ranges. The lixiviant contains oxygen and sodium bicarbonate. The oxygen oxidizes the uranium, which is then complexed with the bicarbonate. The uranium-rich solution (typically ranging from 20 ppm to 250 ppm, but may be higher or lower) will be pumped from the recovery wells to the nearby processing facility for uranium concentration with ion Production Unit Boundari ........

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