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regional and local ground water systems. A general discussion of the regional groundwater <br />conditions is provided in the permit document and summarized here. <br /> <br />Topography is the principal element governing shallow aquifers (100 feet) in this region. <br />Topographic highs act as recharge areas, and lows along streams serve as discharge areas during <br />periods of high water table. In alluvial and other unconsolidated material, ground water moves <br />from high topography to low. This also appears to be the case for the unconfined portions of <br />sandstones in the Dakota and Burro Canyon formations. <br /> <br />Lithology governs the water yielding ability, the aquifer characteristics and the chemical quality <br />of the ground water. The lithology of the NHN Mine area is extremely variable. Shallow <br />aquifers of the area consist of unconsolidated valley deposits of the quaternary system and the <br />stratigraphically variable sandstone, shales and coals of Cretaceous Age (Dakota, and Burro <br />Canyon Formations). Deeper aquifers consist of the varicolored Morrison Formation and the <br />Entrada Formation, both of Jurassic Age. <br /> <br />Structural control on the shallow ground water in the area, i.e., upper Dakota Sandstone and <br />alluvium, appears to be insignificant. Deeper formations, such as the lower Dakota; Burro <br />Canyon; Morrison; and Entrada Formations, whose ground water is under artesian pressure, <br />exhibit piezometric surfaces that conform to structural influence. Water table conditions <br />commonly exist in shallow alluvial aquifers along the larger streams, in principal recharge areas, <br />and in the relatively flat-lying rocks that dominate certain sections of the region. Artesian <br />conditions occur locally throughout the region but are prevalent in the bedrock aquifers of the <br />major structural basin. <br /> <br />The proposed NHN Mine permit area is 0.8 miles north of WFC’s active New Horizon 2 Mine <br />(NH2) and incorporates part of the old Peabody Nucla Mine. Peabody performed detailed <br />hydrologic studies at the New Horizon 1 & 2 mine areas (formerly called the Nucla and Nucla <br />East mine areas respectively). WFC continues to conduct water level and water quality <br />monitoring at the New Horizon Mine. During the spring of 2008, WFC met with the Division to <br />discuss and agree upon a hydrologic monitoring program for the NHN permit area. The resulting <br />plan included the drilling of 9 groundwater hydrologic monitoring wells (GW-N47 through GW- <br />N55) during the fall of 2008 and the establishment of surface water monitoring stations. Details <br />of the surface water monitoring plan are discussed in the following section of this Findings <br />document. <br /> <br />Ground water occurs under both water table and artesian conditions in the permit and adjacent <br />areas. Unconfined groundwater occurs within the Dakota Formation but is generally of poor <br />quality. WFC has installed nine monitoring wells in the Dakota Formation for the NHN mine <br />groundwater monitoring program. Nine new monitor holes (GW-N47 through GW-N55) were <br />constructed in the NHN permit area in October 2008 (shown on Map 2.04.7-1) of the permit <br />document. Typical completion diagrams one each for the overburden, coal zone, and <br />underburden well completion monitoring zones are provided in Figure 1 of Appendix 2.04.7-1. <br />Three sets of nested wells were completed across the permit area to monitor above, within, and <br />below the LDx coal seam. Water level and water quality monitoring began immediately upon <br />completion of these 9 holes on October 10, 2008. Review of the hydrograph data indicates that <br /> <br /> <br /> <br />8 <br /> <br />