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II <br /> in the pit to the bedrock elevation in order to permit dry- <br /> process mining of the remaining material. Arrangements have <br /> i' been made with- tbe- City of Greeley to utilize the available <br /> storm sewer which is located at the northeast corner of the <br /> property, in accordance with the correspondence included as <br /> Exhibit 3. The storm sewer goes due north along the existing <br /> county road from the property corner, and discharges storm <br /> water into the Cache la Poudre River at a point approximately <br /> one mile north of the subject property. <br /> An alternative procedure for removal of the pit drain- <br /> age water from the site- would be the installation of a re- <br /> charge well or wells along the northern edge of the property. <br /> Properly developed and cased, and with adequate pressure <br /> head provided by the sump pump in the pits , recharge wells <br /> could be expected to provide direct return of the pit drain- <br /> ' t age water to the aquifer. <br /> E Geologic cross sections prepared by Lord and Associates <br /> indicate that in the vicinity of the mine area, the aquifer <br /> consists of approximately 12 feet of saturated gravel . <br /> Assumptions regarding permeability of the formation provide <br /> f� the following range of estimates for the amount of water to <br /> be pumped from the pit: <br /> I' Permeability Pit Discharge <br /> f (gpd/ft2) (gpm) <br /> 250 28 <br /> l' 2500 283 <br /> 5000 566 _ <br /> I' Utilizing standard analytical methods for evaluation of <br /> l the ground water hydraulics , it may be shown that for any <br /> I' of the three combinations of permeability and discharge rate , <br /> the- zone of influence of the pit would extend for approximately <br /> mile in all directions . while this result would not normally <br /> be expected from a gravel formation, it arises from the fact <br /> that the saturated thickness in the vicinity is only 12 feet, <br /> -3- <br /> L <br />