URZ Energy receives positive hydrogeologic results showing amenability to ISR mining at Gas Hills
Wednesday, May 02, 2018
URZ Energy Corp. is pleased to announce that it has received the results of detailed in-situ recovery (“ISR”) studies on its Gas Hills uranium project (“Gas Hills”), located in Wyoming, from Hydro-Engineering L.L.C. (“Hydro-Engineering”). Hydro-Engineering was retained to determine the current and predicted future piezometric surface elevations of the Wind River formation confined aquifer, the primary host of uranium mineralization at Gas Hills, in order to evaluate the property’s amenability to ISR uranium mining. Hydro-Engineering is an experienced consulting firm based in Casper, Wyoming, having conducted numerous hydrology studies in the Gas Hills area, and has prepared hydrologic reports for mine permit applications for several existing and planned uranium mines in Wyoming.

The results of the report demonstrate that three of the primary deposits at URZ’s Gas Hills property, being Day Loma, George-Ver, and Loco-Lee, are principally located within a confined aquifer that contains current hydrostatic head well above the minimum requirements to allow for the successful use of ISR mining techniques.

Glenn Catchpole, CEO and Director of URZ, commented: “The Gas Hills uranium district has had a long and storied history of uranium mining dating back to the later 1950s. Though Cameco Corporation has defined ISR resources at their nearby Gas Hills-Peach project, this is the first time that URZ’s Gas Hills property has been evaluated for its amenability to ISR recovery. Our internal hydrologic evaluations on the property suggested that the confined aquifer would have sufficient water pressure (head) to enable the use of ISR mining at a number of our deposit areas, and we are pleased to see the results of Hydro-Engineering’s study confirming such thesis. We look forward to continuing our work at Gas Hills to further evaluate how ISR mining may positively impact future development options.”

Background on ISR

ISR mining of uranium typically requires a mineralized zone to be hosted in a permeable sandstone formation saturated with groundwater under pressure in what is called a confined aquifer. The amount of water pressure is sometimes measured in pounds per square inch, but is more frequently converted to a metric known as ‘head’ and measured in feet. Generally speaking, the more water pressure (head) in a mineralized aquifer, the greater its amenability to ISR mining. To measure the head in a confined aquifer, a cased monitor well is installed in the aquifer and the distance the water level rises in the well is measured as head (in feet). ISR mining typically requires a minimum of at least 20-30 feet of head to be attractive for development.

Hydrogeology at Gas Hills

URZ’s uranium properties in the Gas Hills include five known deposits with NI 43-101 resources, referred to as Day Loma, George-Ver, Loco-Lee, Rock Hill and Bull Rush (see Amended and Restated Gas Hills Uranium Project Mineral Resources and Exploration Target, NI 43-101 Technical Report, prepared for URZ Energy Corp. by Douglas L. Beahm of BRS Inc., effective June 9, 2017). Specifically, the Day Loma, George-Ver and Loco-Lee deposits include established indicated resources which, based on their resource confidence, grade, depth, and hydrogeologic characteristics, were the focus of Hydro-Engineering’s initial study to assess the suitability of the groundwater conditions for ISR mining.

The results of the study completed by Hydro-Engineering include mapping of the current hydrologic head (also known as the piezometric surface) in feet above mean sea level (“MSL”) at each of the three deposits under review, as well as an estimate of the future piezometric surface five years from now. These estimates of future changes in the piezometric surface were conducted as the water levels within the Gas Hills property, and at these three deposits, continue to recover from open pit mining that took place between 25 and 60 years ago. The historic Day Loma open pit is currently in a reclamation state which consists of back-filling the pit to re-establish the surface drainage through the area. The back-filling operation is a State of Wyoming project, has no operational or monetary impact on URZ, and is scheduled to be complete by the end of 2019.

Using monitor well data from the areas of Day Loma, Loco-Lee and George-Ver, Hydro-Engineering constructed water-level maps for the three deposits; one map for the combined Day Loma and Loco-Lee deposits, and one map for the George-Ver deposit. The monitor wells used in this analysis were completed in the Wind River confined aquifer where uranium mineralization is present.

With the exception of the northernmost portion of the Loco-Lee deposit, which will require further review of aquifer characteristics, the three deposit areas are all located within a confined aquifer with sufficient hydraulic head to be amenable to ISR extraction. URZ will continue to evaluate additional geologic and hydrogeologic characteristics at each of the three prospective deposit areas to gauge the number of resource pounds that are expected to be recoverable via ISR mining methods, and how the successful use of ISR mining at Gas Hills could be implemented on a commercial basis.

For more information, please visit: http://urzenergy.com

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