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• direct vicinity of WFC's New Horizon 2 Mine. As seen in the geology discussion (Section 2.04.6) <br />of the permit application, the geology of this region is complex. Consequently, the ground water <br />system is difficult to interpret. To understand the extent the New Horizon 2 Mine may affect the <br />local and regional ground water supply, one must delineate the regional and local ground water <br />systems. <br />To~ograohy. Topography is the principal element governing shallow aquifers (100 feet) in the <br />Canyon Land Section of the Colorado Plateau Physiographic Province. Topographic highs act as <br />recharge areas, and lows along streams serve as discharge areas during periods of high water <br />table. In alluvial and other unconsolidated material, ground water moves forthe most part from high <br />topography to low. This also appears to be the case for the unconfined portions of the Dakota <br />sandstone and Burro Canyon formations. <br />Lithologv. Lithology governs the water yielding ability, the aquifer characteristics and the chemical <br />quality of the ground water. As seen in Section 2.04.6, the lithology of the New Horizon Mine area <br />is extremely variable. Shallow aquifers of the area consist of unconsolidated valley deposits of the <br />quaternary system and the stratigraphically variable sandstone, shales and coals of Cretaceous <br />Age (Dakota, and Burro Canyon Formations). Deeper aquifers consist of the varicolored Morrison <br />Formation and the Entrada Formation both of Jurassic Age. The variability of lithology within each <br />• of the aquifers creates a complex hydrologic system. <br />Table 2.04.5-1 is a summary chart adapted from Boettcher (1972) describing the physical and <br />hydrologic characterof the water bearing formations mentioned above. Included in Table 2.04.5-1 <br />is water quality which is controlled by the reaction of the ground water and the aquifer and the <br />ground water retention time (Hem, 1970). In addition, ground water yields and uses are given. It <br />must be noted that these are generalizations, and these hydrologic properties can vary greatly <br />within the formations. <br />Structural Controls. The New Horizon Mine lies in the Colorado Plateau Physiographic Province <br />within the Canyon Lands Section (Price and Arnow, 1974). This section is an upwarped plateau <br />containing several large folds, laccolithic mountains that rise above the plateau surface, deeply <br />incised drainage and an intricate set of deep canyons (Lohman, 1965; lorns et al., 1965). <br />Structural control on the shallow ground water in the area, i.e., upper Dakota sandstone and <br />alluvium, appears to be insignificant. This is principally due to the large extent of sandstone <br />outcrops. This allows recharge to occur along topographic highs rather than structural highs with <br />water table conditions predominating. However, an artesian head may be developed if a lesser <br />coal bed or sandstone aquifer is confined by impermeable strata. <br />• 2.04.5 - 4 <br />