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The construction of the monitoring holes is subject to the findings of the geophysical <br />logs from the pilot holes but will follow the following general guidelines (See Figure 1). <br />Each hole will be drilled to a diameter of approximately 6-112" Once drilled, the hole <br />will be cased with 4" schedule 40 PVC casing. In the case of the hole that will monitor <br />water above the coal zone, the total depth of the hole will be several feet above the Upper <br />Dakota (UDI) seam the lower ten feet of casing will be mill-slotted PVC Above the <br />slotted casing, a soft-formation packer will be placed on the casing and 3/8" bentonite <br />pellets will be poured down the annulus on top of the packer to an elevation of ten feet <br />above the packer Drill cuttings will then be placed on top of the bentonite pellets to a <br />depth of five feet from the surface. Concrete will be used to grout from the surface to the <br />top of the drill cuttings. <br />The holes monitoring groundwater within the coal zone will be drilled to the bottom of <br />the Lower Dakota (LDx) seam Slotted casing will be used from the total depth to the top <br />of the UD1 seam A soft-formation packer will be installed above the slotted casing and <br />10 feet of bentonite chips will fill the annulus above the packer Drill cuttings will be <br />placed in the hole to a depth of five feet from the surface The final five feet will be <br />grouted with concrete <br />The holes completed below the coal zone will be drilled to a depth of approximately <br />fifteen to 30 feet below the LDx seam. Slotted casing will be used fiom the total depth to <br />just below the bottom of the coal . seam. A soft-formation packer will be placed just <br />below the bottom of the lower seam and 3/8" bentonite pellets will be poured in to a <br />depth of several feet above the UDI seam Drill cuttings will be placed in the hole to a <br />depth of five feet from the surface the final five feet will be grouted with concrete. <br />Map 1 shows the proposed monitoring sites Figure I shows the proposed method of <br />monitor hole construction Figure 2 shows the method of plugging the three pilot holes. <br />Table 1 is a list of the locations and estimated depths of the holes at each nest site. <br />ITEM 5.B.1 None <br />ITEM 5.•B.2 None <br />ITEM 5.B.3 Indian rice grass 9 29# <br />Galleta 20 00# <br />Sand Drop Seed 129# <br />Gamma 3.30# <br />Or as stipulated by the surface land owner <br />ITEM 5.11.4 See Attached Iable I <br />ITEM 53„5 The 9 ground water monitoring holes will monitor water levels and water <br />quality in strata immediately above the UD1 and LDx coal seams; within the coal seam; <br />and immediately below the coal seam at three different locations The strata <br />encompassing the coal seam ate the upper and middle members of the Dakota Formation.