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29 <br /> e &arce5 <br /> Table 2 shows estimates of the transmissivity and hydraulic conductivity of the producing intervals for <br /> the site wells. The average yield per foot of drilled depth of 0.106 is approximately the average of 0.119 <br /> that the USGS found for the county. <br /> Producing Pumping Specific Transm- Hydraulic <br /> Depth Yield Yield/Depth Interval Drawdown Capacity issivity Conductivity <br /> Feet GPM GPM/Ft Feet Feet GPM/Ft GPD/Ft Ft/Day <br /> 235 25 0.106 7 172 90 70.279 419 0.33 <br /> Table 2.--Estimates of transmissivity and hydraulic conductivity of the bedrock under the property. <br /> The value of transmissivity shown in Table 2 was based upon the calculated specific capacity <br /> (Yield/Drawdown) using a multiplier of 1,500 for an unconfined aquifer'. The estimated hydraulic <br /> conductivity was determined by dividing the transmissivity by the producing interval. <br /> Groundwater Occurrence and Movement <br /> The general conceptual model of the occurrence of groundwater in the Piedmont' shown in Figure 3 is <br /> applicable to the property. This model shows that the directions of groundwater movement are generally <br /> from topographic high to low areas and towards water wells and excavations. <br /> Bedrock <br /> Feultzone Joint <br /> —Dike <br /> Modified from Freeze and Cherry,1979 <br /> Figure 4.--Conceptual model of the occurrence of groundwater in the Piedmont of NC. <br /> To illustrate the application of this model to the property, a generalized three-dimensional groundwater <br /> flow model using the USGS Modflow6 Model' was constructed for the project using available <br /> information. The model uses finite difference approximations to solve the groundwater flow equation. <br /> The model covered an area of approximately 2,000 acres centered on the property as shown in Figure 5. <br /> ' Driscoll,F.G. (1986)Ground Water and Wells.2nd Edition,Johnson Division, St.Paul. <br /> s R.Alan Freeze and J.A. Cherry, 1979: Groundwater, 1St Edition. <br /> 6 https://www.usgs.gov/software/modflow-6-usgs-modular-h d�gic-model <br /> 4 <br />