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

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Centennial Project - Section 33 Pumping Test Plan 2 September 2009 Powertech (USA) Inc. 3. Assess hydrologic communication in the mineralized zone between the pumping well and surrounding production zone monitoring wells; 4. Assess the presence of hydrologic boundaries, if any, within the production zone; and 5. Evaluate the degree of hydrologic communication, if any, between the production zone and the overlying and underlying aquifers in the test area. 3.0 GENERAL SITE CHARACTERIZATION The Centennial Project area was extensively investigated by Rocky Mountain Energy (RME) during the late 1970s and early 1980s. Subsequently, Powertech (USA) has resumed exploratory drilling within the vicinity and project development. The project is located within the Cheyenne Basin, a sub-basin of the greater Denver- Julesburg, or DJ, Basin, which is bordered on the northwest by the Hartville Uplift in Wyoming and on the east and northeast by the Chadron Arch in Nebraska (Figure 2). To the south, the Cheyenne Basin is separated from the Denver Basin by the Greeley Arch. To the west, the basin borders the Colorado Front Range (Voss & Gorski, 2007). During Laramide orogeny and uplift of the ancestral Rocky Mountains to the west and subsidence of the Cheyenne and Denver Basins to the east, a thick sequence of sediments, ranging in age from Pennsylvanian to Quaternary, accumulated. The Late Cretaceous Pierre Shale represents offshore marine depositions and has a gradational contact with the overlying Fox Hills Sandstone, which represents near shore deposition and, as noted, is the host rock for the uranium mineralization. Overlying the Fox Hills Sandstone is the Laramie Formation, which consists of terrestrial fluvial deposits (Voss & Gorski, 2007). Unconformably overlying the Laramie Formation is the tuffaceous White River Formation, which contains volcanic fragments and is thought to be a source of the uranium. In the project area, the White River Formation has been deeply eroded with only isolated remnants remaining (Voss & Gorski, 2007). The generalized stratigraphic section (Figure 3) in the vicinity of the Section 33 pumping test is described below. Laramie Formation - This is a late Cretaceous terrestrial, fluvial sequence, comprised of thin, scattered lenticular sandstone lenses, interbedded with siliceous and carbonaceous mudstones and siltstones. In the northern Centennial area, the Laramie is 500 to 600 feet thick. In the southern portion of the project, the Laramie is entirely eroded away. The boundary between the Laramie Formation and the underlying Fox Hills Sandstone is a lagoonal lignite bed. _'W Z= -