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4- 16 <br />• The water flow may be highly variable in various directions and at different locations, <br />depending on the nature of fracturing present. Because fracturing is localized and not <br />continuous, the coal seams do not appear to be significant aquifers. <br />Regional dip of the Mesaverde Formation strata is about three degrees to the northeast and <br />the main groundwater flow direction is governed by this dip. The principal recharge to the <br />aquifers occurs where the aquifers are subcropping beneath the stream beds filled with <br />saturated alluvium. Direct infiltration of precipitation and snow melt on the outcropping areas of <br />water bearing formations is secondary. Due to the lithological character of the Mesaverde <br />Formation -lenticular beds of alternating sandstones, siltstones, shales, claystones, and coals - <br />the vertical component of the recharge due to primary permeability is minimal. The plastic <br />character of the fine grained units also prevents the development of significant secondary <br />(fracture) permeability, so that the vertical recharge due to secondary permeability is also <br />minimal. <br />Local infiltration can develop perched aquifers of limited extent above the stream beds. In <br />• areas where major vertical structures such as faults occur, the vertical infiltration or <br />interconnection between several aquifers can be significant. These conditions were confirmed <br />by the experience in Book Cliffs mines and by results of the overall evaluation of exploration <br />bore holes. <br />Above the stream beds, only limited groundwater occurrence is experienced in the <br />sandstone and coal seams. Beneath the local stream beds, sandstone strata and coal seams <br />are saturated. In cases where these aquifers have well developed fracture systems, they could <br />yield small amounts of water when intersected. A substantial water inflow into the mines can be <br />expected only in cases where the underground workings are connected to major fracture <br />systems (a fault for example) with saturated alluvial sediments of considerable extent. Appendix <br />N details one such fracture system adjacent to the McClave Canyon Mine. <br />The results of exploration drilling_indicated that there are no significant sandstone strata, <br />which could be considered as an aquifer within 50 feet below the Cameo Coal Seam, The typical <br />stratigraphic column in the vicinity of the Cameo Coal Seam is shown in Figure 2.1-12. <br /> <br />M` Volume 1 4 - 29 - 96 <br />