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65 <br /> EnvirotacticS <br /> An Earth Systems Company <br /> 5.0 GROUNDWATER MODELING <br /> Using the Proposed Community Well pump test data from 2024 and 2025, simple groundwater modeling may <br /> be performed using available tools from the North Carolina Department of Environmental Quality2: <br /> • Distance Drawdown Analysis: If we have drawdown measurements at various distances from a <br /> pumping center and want to estimate the transmissivity and storage coefficient of an aquifer <br /> • Reverse Distance Drawdown Analysis: If we know the transmissivity and storage coefficient of an <br /> aquifer and need to estimate how groundwater levels will respond with distance from the pumping <br /> center after some time has elapsed. <br /> • Time Drawdown Analysis: If we have drawdown measurements from one well over time at some <br /> distance from a pumping center and want to estimate the transmissivity and storage coefficient of <br /> an aquifer. <br /> • Reverse Time Drawdown Analysis: If we know the transmissivity and storage coefficient of an <br /> aquifer and need to estimate how groundwater levels will respond over time in a well at some <br /> distance from the pumping center. <br /> • Simple Finite Difference Model: If we estimate groundwater level drawdowns associated with a <br /> pumping center overtime (non-steady state solutions). <br /> As discussed in Section 2 of this report in greater detail, we determined through use of AQTESOLV3 (see <br /> below and Attachment 3) that the average aquifer Transmissivity is approximately 30 square feet/day; <br /> Hydraulic Conductivity is approximately 0.05 feet/day; and Storage Coefficient is approximately 0.06. <br /> 2024 Pump Test 2025 Pump Test <br /> ,000 Gbm W� <br /> oKG BEE -RnOBBEE <br /> Am W Me l AWft <br /> °no� Gmnli,mB ® CUII,K9 <br /> SenR;w, Sentiai <br /> ' Pmpmd°pubmLmmper � Aapatlq,tbs-Cmmin'. <br /> i'sateelers PiRl11lII <br /> A =28.83 fl2ldmy q e 3.49 <br /> 2flyy, <br /> 0.000 <br /> 5 =0.110I 3 =0.006208 <br /> rtw1=0.15]n ° r( 0.211 <br /> ° rtc7=0.42 n ° (c)=a 4 128 <br /> Ee 106 <br /> l <br /> 0 <br /> 1 10 100. 1000. 1.0E+9 ,0 <br /> Tm°e lmnl t. 10. 10a <br /> . t000. t.0Ea1 <br /> 2https://www.deq.nc.gov/about/divisions/water-resources/groundwater-resources/groundwater-management-data-tools-technical-reports <br /> 3 http://www.agtesolv.com/pumping test analysis htm#Variable_Rates <br /> Envirotactics, LLC Page 15 of 20 Groundwater Modeling Report <br /> (732) 449-0077 Project No.6704 <br />