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Energy Fuels Coal, Inc. Southfield Mine - 2004 Annual Hydrology Report <br />April 5, 2005 <br />3.0 GROUND WATER AND SURFACE WATER MONITORING RESULTS <br />3.1 Ground Water Monitoring Results <br />3.1.1 Mine Area <br />In the Mine Area, ground water occurs in surficial alluvial/colluvial deposits and as water table <br />conditions in the sequence of sedimentary rocks corresponding to the Vermejo, Raton, and Poison <br />Creek formations. Due to semi-arid conditions and the limited extent and continuity of the <br />alluvial/colluvial deposits, these units do not store or transmit appreciable quantities of ground <br />water in the general mine area. There is limited lateral or regional continuity of potential water- <br />bearing units due to variable lithology and significant cross-bedding and inter-bedding within the <br />bedrock units. As a result, there are no units known to be an aquifer in this area and bedrock ground <br />water occurrences are limited to isolated units and zones that have sufficient local recharge and <br />characteristics that allow it to store and transmit water. Therefore, in this area, isolated shallow <br />perched ground water zone may develop. Additional "minor" ground water storage may occur in <br />abandoned and flooded mine workings, which serve as collection and storage reservoirs as well as <br />for origination of fracture flows (refer to Section 2.04.7 of the Southfield Mining and Reclamation <br />Plan document for more details). <br />In the Mine Area, the current ground water monitoring program includes the following monitoring <br />wells, located as shown on Figure 1, Mine Monitoring Stations: <br />Well Location Denth/Com leo tion Completion Zone <br />MW-16 E'/zNW'/< Section 30 136ft/106-136ft Jack O'Lantern Coa] Seam <br /> T20S, R69W <br />MW-23 E''/zSW'I4 Section 19 179ft/149-179ft Red Arrow Coal Seam <br /> T20S, R69W <br />MW-65 W%SW%4 Section 24 1,448ft/968-988ft Jack O'Lantern Coal Seam <br /> T20S, R70W <br />MW-NW W'hSW'/4 Section 19 380ft/360-380ft Red Arrow Coal Seam <br /> T20S, R69W <br />Monitoring wells MW-7A, MW-7B, MW-8, MW-10, and MW-22 were previously included in the <br />monitoring program, but have since been mined-through and eliminated from ongoing monitoring. <br />Well MW-8 was mined-through in 1993 and immediately went dry. Subsequent monitoring showed <br />that the borehole had collapsed to a point 336 feet below the surface. The water level recovered and <br />gradually increased from the 280 foot level beginning in early 1996. Measured water levels in this <br />well indicated that sub-surface conditions above the point of collapse had stabilized. In the final <br />quarter of 1999, however, ongoing monitoring indicated that the well had again collapsed at <br />approximately 250 feet below ground surface, making further water level measurements impractical. <br />Caving occurred in MW-10 around May, 1996. The well was dry between May 1996 and early <br />2002, except for March 2001. Monitoring was officially discontinued in October 2003 (TR-35). A <br />former dewatering well, referred to as the North Well, was originally used to dewater mine <br />workings in the Red Arrow Coal Seam north of the main mine. It was discontinued as a dewatering <br />0417/200<annuaihydrpt.doc NWCC INC. Page 7 <br />