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4 Table 2 shows estimates of the transmissivity and hydraulic conductivity of the producing intervals for the site wells. The average yield per foot of drilled depth of 0.106 is approximately the average of 0.119 that the USGS found for the county. Table 2.-- Estimates of transmissivity and hydraulic conductivity of the bedrock under the property. The value of transmissivity shown in Table 2 was based upon the calculated specific capacity (Yield/Drawdown) using a multiplier of 1,500 for an unconfined aquifer4. The estimated hydraulic conductivity was determined by dividing the transmissivity by the producing interval. Groundwater Occurrence and Movement The general conceptual model of the occurrence of groundwater in the Piedmont5 shown in Figure 3 is applicable to the property. This model shows that the directions of groundwater movement are generally from topographic high to low areas and towards water wells and excavations. Figure 4.--Conceptual model of the occurrence of groundwater in the Piedmont of NC. To illustrate the application of this model to the property, a generalized three-dimensional groundwater flow model using the USGS Modflow6 Model6 was constructed for the project using available information. The model uses finite difference approximations to solve the groundwater flow equation. The model covered an area of approximately 2,000 acres centered on the property as shown in Figure 5. 4 Driscoll, F.G. (1986) Ground Water and Wells. 2nd Edition, Johnson Division, St. Paul. 5 R. Alan Freeze and J.A. Cherry, 1979: Groundwater, 1st Edition. 6 https://www.usgs.gov/software/modflow-6-usgs-modular-hydrologic-model Depth Yield Yield / Depth Producing Interval Pumping Drawdown Specific Capacity Transm- issivity Hydraulic Conductivity Feet GPM GPM/Ft Feet Feet GPM/Ft GPD/Ft Ft/Day 235 25 0.106 172 90 0.279 419 0.33 124