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

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Centennial Project - Section 33 Pumping Test Plan 3 September 2009 Powertech (USA) Inc. Fox Hills Sandstone - The Fox Hills was deposited as part of the final retreat of the Cretaceous Seaway from North America. The Upper Fox Hills Sandstone represents shoreline deposits, comprised of lagoonal muds, barrier island sands and tidal and distributary channel sands. The Lower Fox Hills represents deeper marine deposition such as delta front, offshore bar and distributary sands, along with offshore muds and silts. The Fox Hills Sandstone is generally subdivided into the Upper and Lower Fox Hills Members. Upper Fox Hills Al Sand - The A, Sand immediately underlies the lignite sequence at the base of the overlying Laramie Formation. The A, is primarily a channel sand, 0 to 35 feet thick. When absent, this stratigraphic interval contains mudstones, siltstones and carbonaceous clays. When present, there is usually a 5-8 foot confining layer of clays at the base of this unit, between the Ai Sand and A2 Sand. In the central portion of the Project area, the Al Sand scours down into the A2 Sand, removing any confining clays and resulting in a single AVA2 Sand with a total thickness of up to 60 feet. In this central portion of the project area (Sections 9 & 10, T9N, R67W), the Al Sand has uranium resources of interest. A2 Sand - The A2 Sand immediately underlies the Al Sand and is the most significant • host sandstone within the project area, containing approximately 70% of all identified resources. Past exploration drilling encountered a continuously mineralized oxidation/reduction boundary of over 20 miles within this sand unit in the Centennial area. It is approximately 30 feet thick in the northern portion of the project area and as much as 60 feet thick in the southern portion. In the central and north-central portion of the project area, these barrier island sands have been cut into, and in some cases, replaced by thick distributary channel sand sequences. A2 Confining Unit - Underlying the A2 Sand is the A2 Confining Unit. This unit averages 6 to 8 feet thick and is consistently present throughout most of the Centennial Project. Analyses on core from the 2007 drilling program showed vertical permeabilities ranging from 8 x 10-8 to 5 x 10-9 centimeters per second (Powertech USA, Inc., nd). In the central portion of the project area, there is a small area where this unit has been removed by an Al Sand channel, resulting in a combined AVA2 Sand averaging 60 feet thick. A3/A4 Sand - The A3/A4 Sand is a highly variable unit, containing from 0 to 35 feet of sand. Throughout most of the project area, this unit consists of thin A3 and/or A4 beach and channel sands, interbedded with mudstones and siltstones. In places, active channeling within these sands resulted in the formation of a massive A3/A4 Sand, which scoured down into the underlying WE Sand. This sand unit is unmineralized within the Centennial Project area, with the exception of Section 32 & 33, T10N, R67W, where a 0 small resource area has been developed within a 35-foot thick channel sandstone.