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Exhibit G CIIILRB 112 Permit Application Agile Slone Systems. Inc. • are not conventionally deemed as bedrock aquifers, although small volumes of water may occur as springs and seeps or flow into wells. Fracturing associated with faulting and folding provides porosity and enhances permeability in bedrock units. These fractures, when occurring in normally "impermeable" rocks such as granites or low-permeability sedimentary rocks such as limestones and silty shales, allow ground water to occur and move. Springs and wells in the project region tab fractures in the Precambrian rocks, and in the Greenhorn, Cazlisle and Niobrara Formations. Other springs and wells tap intergranular porosity and permeability in parts of the Dakota Group, which may be augmented by fractures. Ground water flow in the bedrock units begins with deep percolation of a part of annual precipitation, plus infiltration of surface waters where streams cut these aquifers, in upland areas. Ground water is driven by gravity down flow paths (in fractured aquifers, in the more intensely fractured volumes) toward dischazge areas such as springs, seeps and subcrop areas beneath outwash deposits. Fast, shallow flow paths may be characterized by low TDS, relatively low temperature ground water. Conversely, slow, deep flow paths may be characterized by high TDS and relatively high temperatures. Several types of flow paths may converge in one discharge • azea. If a predominantly horizontal flow path is interrupted by a relatively impermeable fault, horizontal ground water flow may stop or be slowed significantly and vertical flow or leakage may occur in fractures located away from the main fault. Faults that occur in the project area appeaz to limit lateral ground water flow within bedrock aquifer units to fault blocks. Johnston (1952) notes that most faults in the Parkdale area have throws exceeding 60', which is sufficient to hydraulically separate individual aquifer units within the Mesozoic sediments. Faults do juxtapose relatively permeable rock (such as the Dakota Sandstone) against relatively impermeable rock (say, Graneros Shale and Cazlisle Formation); an example of this is located about two miles south of US 50, on the Copper Canyon road just south of the turnoff to the south entrance of the Royal Gorge. Slow vertical inter-aquifer water movement may occur in fractures located adjacent to faults. Southwest and southeast of the project area, faults mapped by the USGS (see previous geologic map) serve to hydraulically isolate the project area bedrock block from areas to the south. These boundaries, combined with the Arkansas River as a constant-head boundary, localize project impacts to the immediate project area. Water chemistry of the bedrock aquifers is distinct from surface and outwash aquifer waters. Water from the Depot, Clazk, Wootton and northwest wells has markedly greater TDS concentrations, plus a shift in water type toward calcium-sodium sulfate. • zz