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required drilling fluids and drill cuttings and incident precipitation, while maintaining a minimum of approximately one-foot of freeboazd. The upslope diversion ditches will be inscribed when the slope above the pad is greater than 10 percent. In the event persistent runoff occurs from the disturbed area, silt fences or other temporary sediment control measures may be employed to minimize off-site sediment transport. Once the topsoil is removed, drill sites will be leveled as requued to accommodate the drill rig and support I equipment. Typically, two to three mud pits will be excavated for each drill site and the material removed from the pits will be placed adjacent to the pit or in the azea of the pit. The pits will be approximately ] 0 ft x 10 ft x 5 e even a t Iona p re-regmre a co t o ~vitlrin~ the existing pits. If the pits will not hold water, i.e. the excavation is into gravels or sands; they will be lined to retain the drilling fluids. It is in the best interest of the driller to keep drilling fluids in the pit. Drilline Methods and Eauipment: Exploration coreholes will be established with arubber-tired, truck-mounted air/foam rotary drill. Drilling mud may be employed in the drilling medium. Previous drilling activities in the immediate area have not encountered water-bearing formations producing any appreciable quantities of water from the strata overlying the coal seam of interest. Both the Twentymile Sandstone and Wadge Seam Overburden have been documented to contain water; however, neither typically exhibits sufficient head to produce flows at the surface. Drillhole depths projected for each site aze specified on 2005 NOI Table 1. After drilling, the holes will be logged with a standard suite of geophysical data logging instruments. No holes will be developed as water wells. When the drillholes are collared, surface casing will be set to assure that drilling fluids aze not lost to the surficial soils. The surface casing will be grouted in place and then the hole will be advanced using conventional au/foam rotary drilling methods. The surface casing at all three sites will have a threaded surface collaz to allow for quick shut-in of the hole in the unlikely event that significant ground water flows are encountered. The coal will be cored and the drillholes geophysically logged. Upon completion of the coring and logging, the drillholes will be tremie grouted through and twenty feet above the Wadge Coal Seam. From that point up, the holes will either be grouted or backfilled with cuttings to within ten feet of the surface. The interval from ten feet to within three feet of the surface will be grouted, and the remaining three feet will be backfilled with soils. The surface casing will be cut off three feet below the surface or it may be removed entirely. The drillholes will be surveyed to establish site coordinates to permanently locate the drillholes. Reclamation Plan: Reclamation activities will begin once mud pits aze sufficiently dry to allow regrading of each site to occur. Materials excavated for the mud pits will be backfilled into the pits or redistributed over the site, stockpiled topsoil will be spread, and broadcast seeding will occur over the entire disturbed area using one or more of the following approved seed mixtures from Pernut No. C-81-044 (as appropriate, based on the revegetated community and land use). CROPLAND Species Seeding Rate (PLS ]bs/acrel Winter Wheat and/or Alfalfa 60 PASTURELAND Species Seedine Rate (PLS lbs/acrel Smooth Brome 7.0 Intermediate Wheatgrass 6.0 Crested Wheatgrass 3.0 Alfalfa 1.0 Total: 17.0 G:\Environmental\EXPLORATION WORK\EXPLR 2005 BIG ELK private land\Big Elk NOI App. Fomi.doc Page 7 of 8