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E 1 Longwall Panel Methane Drainage Wells Project Plan <br />Technical Revision No. 111; <br />Page 3 of 13 <br />incorporating drill hole data generated through a USGS and U.S. Bureau of Mines drilling <br />program. The following year Johnson further described the geology of the Minnesota Creek area <br />in USBM Technical Paper 721. More recently, in 1989, C. R. Dunrud compiled a coal resources <br />map of the region (USGS Map C-115). In 1998 the Colorado Geological Survey published, <br />"Availability of Coal Resources in Colorado: Somerset Quadrangle, West-Central Colorado <br />(CGS Resource Series 36)". <br />The general stratigraphy of the area consists of members of the Mesa Verde Formation of the <br />Upper Cretaceous System underlying the Wasatch Formation of Tertiary Age. The Barren <br />Member of the Mesa Verde formation crops out lowest in the area with the overlying Ohio Creek <br />member exposed along many of the steeper slopes. Above the Mesa Verde, rocks of the Wasatch <br />Formation are exposed. The Upper and Lower Coal Members of the Mesa Verde Formation are <br />the major coal-bearing units in the area. The A (King), B (Somerset), and C (Bear) coal beds of <br />the Lower Coal Member and the D (Oliver), E (Hawks Nest), and the F-Seam coal beds of the <br />Upper Coal Member have all been mined within the North Fork Valley. <br />General dip in area of the methane drainage project drilling is 3 to 4 degrees to the northeast. <br />Stratigraphic displacements and faults are known to occur in West Elk Mine. Known geologic <br />data does not indicate that these faults are locatable on the surface. <br />• WATER RESOURCES <br />The town of Paorua is situated about 10 miles west of the area and receives an average of <br />approxunately 15 inches of precipitation annually. Given that precipitation increases as elevation <br />increases, the annual precipitation at the proposed well sites would be expected to be somewhat <br />higher than that received at Paonia. An estimated 75% of the annual precipitation occurs during <br />late winter and early spring, mostly as snowfall. June, July, and August are often the driest <br />months. <br />Drainage from the well pads for the proposed project primarily enters the Deep Creek and Dry <br />Fork drainages that are tributary to the North Fork of the Gumuson River. No riparian, wetland <br />or stream habitat will be affected by drilling activities. The roads will be constructed in <br />accordance with USFS low-volume road requirements. <br />The alternate sediment controls used for the drill pads will consist of a slash, silt fence, erosion <br />control blankets, or straw wattles placed on the out slopes of the pad. The demonstration that the <br />alternative sediment control measures meet the limitations of Rule 4.05.2 and 4.05.5 are <br />contained in the attached SEDCAD results calculated for 0.25, 0.5-, 1.0- and 2.0-acre typical pad <br />sites. Previous Methane Drainage Well Pad experience shows that pad size is dependent on <br />number of holes drilled from the pad and depth of overburden that determines the mudpit sizing, <br />hence the 4 different pad size designs. The average pad size from the B Seam MDW drilling was <br />0.495 acre. Mudpits when constructed will be in native soils and if constructed on fill will be <br />constructed on 3:1 side-slopes to meet the 1.56 factor of safety using the Gas Well Pad Slope <br />Stability Analysis (attached). <br />3 <br />