Laserfiche WebLink
• Ground Water Hydrologic Zones <br />The principal factor controlling the occurrence and availability <br />of groundwater in any area is geology. As noted by Price and <br />Waddel (1973), nearly all of the region surrounding the mine permit <br />area is underlain by rocks of marine and continental origin, con- <br />sisting predominantly of interbedded sandstones and shales. Be- <br />cause most of the rocks in the region are consolidated, their <br />water-bearing properties are largely dependent on secondary porosity <br />(faults, fractures, joints, etc.). <br />As noted in the discussion of the geologic setting of the basin, <br />three distinct, mappable lithologic facies or stratigraphic units <br />• have been defined, each of which poses potentially different <br />hydrologic properties. Only the Upper Williams Fork Formation, <br />consisting predominantly of sandstones of terrestrial origin, is <br />considered to have any influence on the alluvium. <br />Groundwater Movement <br />Groundwater movement in the Upper Williams Fork (Upper Sandstone <br />Facies) was determined through the construction of potentiometric <br />surface maps. As described in Section II.C-Hydrology, groundwater <br />movement in the Upper Sandstone Facies above the coal follows the <br />trend and dip of the gentle limb of the Red Wash syncline until <br />topographic control takes over near the White River. As a result, <br /> a groundwater divide exists and generally follows the northern <br />• boundary of the lease area. The figure indicates that recharge <br /> to this zone occurs in the topographically higher hills to the <br />II.D-10 <br />4/81 <br />