HYDROLOGY - 9/4/2009, 7:15:47 AM-JWD

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Centennial Project - Section 33 Pumping Test Plan 4 September 2009 Powertech (USA) Inc. A4/WE Confining Unit - As noted above, the A3/A4 Sand locally is scoured through the A4/WE Confining Unit into the underlying WE Sand. As such, the confining unit is discontinuous. WE Sand - Underlying the A3/A4 Sand is the WE Sand, which is a major host for uranium mineralization in the southern portion of the project area. Historic drilling encountered 12 to 15 miles of continuously mineralized oxidation/reduction boundary within this sand. Similar to the A2 Sand, the WE Sand is a typical barrier island sandstone, averaging 30 to 50 feet thick. In the central portion of the project, combined A3/A4 Sand and WE Sand thickness exceeds 60 feet as a result of channeling. AB Confining Unit - This confining unit separates the Upper Fox Hills from the Lower Fox Hills and underlies the entire project area. It averages 20 feet in thickness and consists of clays, carbonaceous muds and some washover sands. Lower Fox Hills B Sand - The B Sand is a delta front, foreshore sand that underlies the entire project area. It has a characteristic coarsening-upward electric log response and has a total thickness of approximately 125 feet. Most of the domestic wells in the project area are producing from this sand unit. There is a weakly mineralized oxidation/reduction boundary in the upper portion of this sand. • C Sand - The C Sand is an offshore bar sand that is present only in the northeast portion of the project area. It is a 100-foot thick sandstone unit that is shown to be weakly mineralized in historic drilling. 4.0 MONITORING WELL CONFIGURATION and INSTALLATION In the Section 33 area, the primary target zone with respect to uranium mineralization is in the A2 Sand. There are also zones within both the underlying A3/A4 Sand and the WE Sand units that contain uranium. Because of scouring through the intervening confining units during deposition of the overlying units, adjacent sand unit may be contiguous and the intervening confining unit discontinuous. Given the occurrence of mineralized zones with multiple sand units and the discontinuous nature of the intervening confining units, consideration is being given to applying for an aquifer exemption for the entire sequence above the AB Confining unit including both the A and WE Sands. For the purpose of the proposed pumping test, the focus is on the hydrogeological characterization of the A2 Sand and the degree on hydraulic communication, if any, between the production zone and the overlying and underlying aquifer, namely the Laramie Formation and the B Sand. The proposed layout of the Section 33 Pump Test is shown on Figure 4. As shown, the layout includes a central pumping well (PW1) to be completed in the A2 Sand. Three A-- rl 5010Z, _122