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The target interval depth for the two deep monitoring wells will be approximately between 800 and 1,100 feet <br />below ground surface (bgs), with the shallow monitoring well being approximately 10 to 25 feet; however, the <br />exact screen intervals shall be determined by geophysical log analyses and interpretations that will be <br />performed by Denison upon reaching target drill depth and prior to construction of the wells. <br />Construction details for the monitoring wells, including planned screened intervals, materials of construction, <br />and approximate depths are shown in Attachment B. <br />The wells will be installed using a typical truck mounted drill rig with rubber tires. A surface pit will be <br />required to collect cuttings and drilling fluids. <br />Estimated surface disturbance area for each well is conservatively assumed to be 50 feet by 100 feet (5,000 <br />square feet each), and the well access roads are estimated to total approximately 0.89 acres of new access roads. <br />In preparation for setting up the drill rig, a small surface area will be cleared with a small bulldozer. A small <br />skidsteer will be used to move pipe at the site during drilling activities, and it is likely that several pickup trucks <br />will be used to transport personnel to the site. It is not anticipated that any trees will be removed during site <br />preparation and drilling of the wells without BLM approval. Topsoil will be pushed to one side and <br />redistributed following drilling grading and seeding of disturbed areas around the wells. Access roads to the <br />wells are strategically placed to minimize disturbance and will be approximately 15 feet in width. <br />Well installation will begin upon approval of this proposal by the BLM and environmental clearance and <br />bonding is put in place. Denison hopes to begin well installation mid-April 2011. Well installation activities <br />are anticipated to take approximately 1.5 months; however, inclement weather could prevent access to the sites, <br />and drilling activities may extend for two months. Reclamation of affected areas not used for continued well <br />access will occur immediately after drilling is complete. <br />Drilling activities will be completed during daylight hours and will require from 3 to 6 people. <br />Reclamation Plan <br />The reclamation activities following well drilling activities are discussed above. When no longer required for <br />monitoring, these wells will be abandoned in accordance with Colorado Rule 16 of the Well Construction Rules <br />by filling the well to the static water level with drill cuttings, clean sand, or clean gravel, then with clean native <br />clays, cement or high solid bentonite grout to the ground surface. The uppermost five (5) feet of casing shall be <br />filled with grout or a permanent watertight cover shall be installed at the top of the casing. If the casing is <br />removed, the hole shall be filled as described above to within five (5) feet of the ground surface. The top five <br />(5) feet of the hole shall be filled with materials less permeable than the surrounding soils that are adequately <br />compacted to prevent settling. <br />Topsoil from the pad areas will be pushed to one side of the disturbed area and leveled for use in reclamation. <br />This topsoil will then be pushed back to cover the drill hole area during reclamation. All disturbed areas will be <br />ripped and seeded in the late fall. Reclamation will occur concurrently following disturbance whenever <br />possible. <br />Access roads to the exploration areas are typically off of main roads that will remain in use in the area for <br />recreation and grazing as well as multiple other uses; therefore, only the access roads to the wells off of the <br />main roads are proposed for reclamation activities. The disturbed area associated with these proposed access <br />DENISONID„ <br />MINES <br />2