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GENERAL HYDROLOGY DESCRIPTION <br />The King I Mine operation has little impact on groundwater systems and its <br />impact on the surface hydrology is moderate. Future operations in the upper <br />Menefee coal seam are not expected to disrupt aquifers, streams, water systems, or <br />the small watershed (up-slope areas of the mine site). Hydrologic data obtained from <br />the existing mine workings, core drill holes in the mine plan area, and other <br />research studies show that the mining operation has had only a mild impact on <br />water sources of Hay Gulch (See Appendix 4). <br />The mining bench is located in the upper reaches of the Hay Gulch drainage <br />system. All wells, diversion ditches, sedimentation ponds, water conveyances and <br />storage, and the surface facilities are shown on Map King I-007, the mine surface <br />drainage map. <br />DRAINAGE PLAN <br />The drainage plan for the National King I Mine will consist of diversion of <br />uncontaminated water originating upstream of the mine yard, through the yard to <br />the discharge point at the north end of site. Runoff generated on the yard itself as <br />well as runoff from two small natural areas adjacent to the yard will be collected and <br />routed through the sedimentation ponds. <br />Refer to 2.05.6 (Hydrologic Balance) and Appendix 11 for a detailed <br />description of Mine Surface Drainage and Sediment Ponds design and descriptions. <br />SUB-SURFACE HYDROLOGY <br />Generally, National King Coal, LLC does not encounter ground water during <br />the course of normal mining operations for process water. National King Coal, LLC <br />estimates a consumptive use of 8.61 acre feet per year, for use in dust control <br />operation. The three continuous mining machines, each feeder breaker and belt <br />transfer points are sprayed to reduce dust. Process water is obtained by means of <br />the two wells, one located in the Hay Gulch Valley Floor, and the other on the mine <br />bench, as shown on Map King I-007. Occasionally, localized areas of water are <br />encountered in the mine floor. These are believed to be Aperched@ aquifers as the <br />usually dry up after a short time. <br />AQUIFERS <br />The King I Mine is not in a major groundwater recharge area. Research shows <br />this portion of the basin has had very limited ground water development. Most of <br />the wells in the general area have been completed in the unconsolidated alluvial <br />gravels and terrace deposits of the La Plata River and its tributaries (including Hay <br />Gulch), or in consolidated aquifers further south (down-dip) in the basin. Two <br />formations, the Cliff House sandstone and the Menefee Formation are important and <br />relative to the proposed mining operations. The underlying Point Lookout sandstone <br />will not be affected by the mining operations. <br />CLIFF HOUSE SANDSTONE <br />This unit comprises the cap rock to the dip slopes of the area. Based on <br />information provided by the Menefee Land Company exploration drilling program for <br />a proposed coal mine bordering the King I Mine, the sandstone is not saturated and <br />is above the potentiometric surface in the immediate project vicinity. No water was <br />National King Coal, LLC King I Mine <br />Section 2.04.7 <br />Page 2 February, 2007 <br />