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o Discharge from outcrop to stream channels; and <br />In general, the underlying porous media would have the following relative hydrogeolgoic <br />properties based on the composition of the formations. <br />Formation General Description Porosity Transmissivity <br />Morrison Formation Mudstone with fine 0-10% (Freeze and Low in the upper <br /> grained interbedded Cherry, 1979) Morrison. Low to <br /> sandstone. The medium in the lower <br /> Morrison shales are Morrison (Gloyn, <br /> confining layers, 1995). <br /> while the lower <br /> Morrison sandstones <br /> are aquifers. <br />Junction Creek Fine to coarse 5-30% (Freeze and Above average <br />Sandstone grained eolian Cherry, 1979) permeabilities and <br /> sandstone porosities <br />Wanakah marl Fine grained Very low to low Very low to low <br /> sandstone mudstone except in areas of <br /> and marl fracture and faults <br /> (Gloyn, 1995) <br />Wanakah - Pony Laminated micritic Very low to low Very low to low <br />Express Limestone and algal limestone (Gloyn, 1995) except <br /> in areas of fracture <br /> and faults. <br />Entrada Formation Fine to coarse 5-30% (Freeze and Very low to low <br /> sandstone Cherry, 1979) (Gloyn, 1995) <br />Dolores Formation Shale and siltstone 0-10% (Freeze and Variable generally <br /> with interbedded Cherry, 1979) low. <br /> sands and <br /> conglomerates <br />When examining the recharge potential for the site, it would appear to be extremely low as <br />the underlying geologic formations are generally low permeability layered material which <br />would inhibit recharge of water from the slopes to the underlying formations. In addition to <br />the low permeability material, onsite observations indicate that the alluvial/fluvial cover on <br />the hillsides is extremely thin and the hillsides are relatively steep. These two factors will <br />tend to reduce the time of concentration of any overland flow from precipitation or snow <br />melt events thus minimizing the amount of recharge that could enter the ground water <br />system. Additionally, the faulting in the area has caused offsets of geologic formations that <br />place units of differing permeability and porosity in contact with each other thus effectively <br />limiting the flow of potential recharge water from areas of high potential to lower potential. <br />Frequently, if geologic formations of differing permeability are in contact on slopes where <br />recharge is occurring, the near surface recharge is forced back to the surface and either <br />springs or enhanced vegetation can be found along these zones. Finally, this same faulting <br />has created small, isolated areas for potential recharge to infiltrate the bedrock in the local