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<br />' 10. <br />' test and computer simulation. Using the Darcy equation, flow <br />' to the pit was calculated to be 120 ft3/day as given below. <br />Inflow = Til, <br />' where T = transmissivity <br />i = hydraulic gradient <br />' 1 = length of pit wall intercepting groundwater <br />flow. <br />' Such that: Inflow = (210 gpd/f t) (0.00859) (500 ft) ( ft3 ) <br />7.48 gal <br />' = 120 ft3/day or 0.62 gpm <br />' A second independent method was used that utilized estimated <br />precipitation values and infiltration rates. Calculations and <br />' assumed values are given below. <br />' Inflow = infiltration over surface area of proposed pit, <br />Such that: Inflow = (630,000 ft2) (0.083 ft/year) <br />52,300 ft3/year or 143 ft3/day or 0.74 gpm <br />Because the values obtained from these two methods are similar, <br />the values assumed for transmissivity are realistic. However in <br />' consideration of the many assumptions made, it is estimated that <br />inflow is in the range 0.5 to 1 gpm. <br />Inflows into this pit are significantly lower than the existing <br />pit as a consequence of the current mine plans which limit the <br />base of the pit to the elevation of the projected surface of <br />Stollsteimer Creek. <br />r <br /> <br />1 <br />D R PiTEgUd g5S0Ciq TES li4iiED <br />