Project Description: A town is planning to expand its water supply by constructing a pumping well in an unconfined sand and gravel aquifer as shown in Figure I. The well is designed to pump constantly at ante of 18,000 m'day. Well construction was stopped by the Environment Public Authority (EPA) who claimed that pumping would significantly reduce groundwater discharge to the wetland and impact harmfully the ecosystem. In addition, the high pumping rate would lower discharge to the river and influence downstream water availability. The town claimed the fully penetrating river boundary to the north and groundwater divide located near the center of the valley would prevent any change in flow to the worlund Phase (1) Model Construction The length of the aquifer valley is represented through 40 rows of cell, each vihacell size dy = 150m. The width of the valley is represented by 18 columns with size A1 = 30 m The model 18 a single unconfined aquifer with abortion and up elevations 980 and 100, respectively. Arcal recharge ocus at along sverage uniform rate of 0.001 ml day. An unconfined aquifer horizontal hydraulic conductivity of 50 m day is used, and the anisotropy nato is 10. The specific yield of the aquifer is 0.1. The wel field is located in cell (ijk)= (62.). The condutivity of the river het is K = 50 ndry , and the thicknes of the riverbed is = 1 n. The hydraulic heads along rows 1 and 40 represents the kevels of water in the river and weland 100 m, where the no flow cells should be assigned along the columns 1 and 18. SATE MOUNTAIN SUGE MOUNTAINS VILLE 0 Phase (2&3: Analysis & Results L'sing your program, provide results for the following the nesment scenarios. 0200 Wetland AREALOWE $ WELL RIVER 1. Scenario A: Pre development conditives / SteadyState Construct a three dimensional steady-state model of the aquifer between the river and weland for conditivas prix tu panping using the informativa in Figure 1. River and weland represent boundaries as constant head boundaries with head set at 1000 n. The side boundaries are n-flow boundaries. Draw the water table profile in a north-south Cros scrin and label the simulated groundwater divide between the river and weland Discus the natural flow regine. Discus the model mais balance. Compute the discharge to the river and weiland. SUATOROK PAT AND WATER Figure 1: Map and cross-section of the aquifer and location of the proposed fully peretrating pumping well / 500n from the river Scenario A_R: Run the model in scenario but this time assure with the width of the river is 3 m and the devation of the bottom of the sediments is 95 m. Compare the results with those in scenario A. What is the efict of reducing the withof the river? Project Description: A town is planning to expand its water supply by constructing a pumping well in an unconfined sand and gravel aquifer as shown in Figure 1. The well is designed to pump constantly at a rate of 18,000 m/day. Well construction was stopped by the Environment Public Authority (EPA) who claimed that pumping would significantly reduce groundwater discharge to the wetland and impact harmfully the ecosystem. In addition, the high pumping rate would lower discharge to the river and influence downstream water availability. The town claimed the fully penetrating river boundary to the north and groundwater divide located near the center of the valley would prevent any change in flow to the wetland. RIVER ELEV 1000m 1500 m -2250-2250 - SLATE MOUNTAINS SLATE MOUNTAINS VALLEY 8500 m 10.000 m 4500 m Wiel Q - 20,000 mid Wetland ELEV 1000m AREAL RECHARGE 0.001 mild WELL RIVER Wetland METERS 1020 1000 9801 SANO & GRAVEL K50 mild SLATE BEDROCK PEAT AND WATER Figure 1: Map and cross-section of the aquifer and location of the a proposed fully penetrating pumping well 1500 m from the river. Phase (1): Model Construction The length of the aquifer valley is represented through 40 rows of cells, each with a cell size Ay = 250 m. The width of the valley is represented by 18 columns with size Ax = 250 m. The model uses a single unconfined aquifer with a bottom and top elevations 980 and 1020, respectively. Areal recharge occurs at along average uniform rate of 0.001 m/day. An unconfined aquifer horizontal hydraulic conductivity of 50 m/day is used, and the anisotropy ratio is 10. The specific yield of the aquifer is 0.1. The well field is located in cell (1.j,k) = (6,9,1). The conductivity of the river bottom is Kriv = 50 m/day, and the thickness of the riverbed is = 1 m. The hydraulic heads along rows 1 and 40 represents the levels of water in the river and wetland 1000 m, where the no flow cells should be assigned along the columns 1 and 18. Phase (2&3): Analysis & Results Using your program, provide results for the following three assessment scenarios. 1. Scenario A: Pre-development conditions/ SteadyState Construct a three dimensional steady-state model of the aquifer between the river and wetland for conditions prior to pumping using the information in Figure 1. River and wetland represent boundaries as constant head boundaries with head set at 1000 m. The side boundaries are no-flow boundaries. Draw the water-table profile in a north-south cross section and label the simulated groundwater divide between the river and wetland. Discuss the natural flow regime. Discuss the model mass balance. Compute the discharge to the river and wetland. Scenario A_R: Run the model in scenario A but this time assume with the width of the river is 5 m and the elevation of the bottom of the sediments is 995 m. Compare the results with those in scenario A. What is the effect of reducing the width of the river? Project Description: A town is planning to expand its water supply by constructing a pumping well in an unconfined sand and gravel aquifer as shown in Figure I. The well is designed to pump constantly at ante of 18,000 m'day. Well construction was stopped by the Environment Public Authority (EPA) who claimed that pumping would significantly reduce groundwater discharge to the wetland and impact harmfully the ecosystem. In addition, the high pumping rate would lower discharge to the river and influence downstream water availability. The town claimed the fully penetrating river boundary to the north and groundwater divide located near the center of the valley would prevent any change in flow to the worlund Phase (1) Model Construction The length of the aquifer valley is represented through 40 rows of cell, each vihacell size dy = 150m. The width of the valley is represented by 18 columns with size A1 = 30 m The model 18 a single unconfined aquifer with abortion and up elevations 980 and 100, respectively. Arcal recharge ocus at along sverage uniform rate of 0.001 ml day. An unconfined aquifer horizontal hydraulic conductivity of 50 m day is used, and the anisotropy nato is 10. The specific yield of the aquifer is 0.1. The wel field is located in cell (ijk)= (62.). The condutivity of the river het is K = 50 ndry , and the thicknes of the riverbed is = 1 n. The hydraulic heads along rows 1 and 40 represents the kevels of water in the river and weland 100 m, where the no flow cells should be assigned along the columns 1 and 18. SATE MOUNTAIN SUGE MOUNTAINS VILLE 0 Phase (2&3: Analysis & Results L'sing your program, provide results for the following the nesment scenarios. 0200 Wetland AREALOWE $ WELL RIVER 1. Scenario A: Pre development conditives / SteadyState Construct a three dimensional steady-state model of the aquifer between the river and weland for conditivas prix tu panping using the informativa in Figure 1. River and weland represent boundaries as constant head boundaries with head set at 1000 n. The side boundaries are n-flow boundaries. Draw the water table profile in a north-south Cros scrin and label the simulated groundwater divide between the river and weland Discus the natural flow regine. Discus the model mais balance. Compute the discharge to the river and weiland. SUATOROK PAT AND WATER Figure 1: Map and cross-section of the aquifer and location of the proposed fully peretrating pumping well / 500n from the river Scenario A_R: Run the model in scenario but this time assure with the width of the river is 3 m and the devation of the bottom of the sediments is 95 m. Compare the results with those in scenario A. What is the efict of reducing the withof the river? Project Description: A town is planning to expand its water supply by constructing a pumping well in an unconfined sand and gravel aquifer as shown in Figure 1. The well is designed to pump constantly at a rate of 18,000 m/day. Well construction was stopped by the Environment Public Authority (EPA) who claimed that pumping would significantly reduce groundwater discharge to the wetland and impact harmfully the ecosystem. In addition, the high pumping rate would lower discharge to the river and influence downstream water availability. The town claimed the fully penetrating river boundary to the north and groundwater divide located near the center of the valley would prevent any change in flow to the wetland. RIVER ELEV 1000m 1500 m -2250-2250 - SLATE MOUNTAINS SLATE MOUNTAINS VALLEY 8500 m 10.000 m 4500 m Wiel Q - 20,000 mid Wetland ELEV 1000m AREAL RECHARGE 0.001 mild WELL RIVER Wetland METERS 1020 1000 9801 SANO & GRAVEL K50 mild SLATE BEDROCK PEAT AND WATER Figure 1: Map and cross-section of the aquifer and location of the a proposed fully penetrating pumping well 1500 m from the river. Phase (1): Model Construction The length of the aquifer valley is represented through 40 rows of cells, each with a cell size Ay = 250 m. The width of the valley is represented by 18 columns with size Ax = 250 m. The model uses a single unconfined aquifer with a bottom and top elevations 980 and 1020, respectively. Areal recharge occurs at along average uniform rate of 0.001 m/day. An unconfined aquifer horizontal hydraulic conductivity of 50 m/day is used, and the anisotropy ratio is 10. The specific yield of the aquifer is 0.1. The well field is located in cell (1.j,k) = (6,9,1). The conductivity of the river bottom is Kriv = 50 m/day, and the thickness of the riverbed is = 1 m. The hydraulic heads along rows 1 and 40 represents the levels of water in the river and wetland 1000 m, where the no flow cells should be assigned along the columns 1 and 18. Phase (2&3): Analysis & Results Using your program, provide results for the following three assessment scenarios. 1. Scenario A: Pre-development conditions/ SteadyState Construct a three dimensional steady-state model of the aquifer between the river and wetland for conditions prior to pumping using the information in Figure 1. River and wetland represent boundaries as constant head boundaries with head set at 1000 m. The side boundaries are no-flow boundaries. Draw the water-table profile in a north-south cross section and label the simulated groundwater divide between the river and wetland. Discuss the natural flow regime. Discuss the model mass balance. Compute the discharge to the river and wetland. Scenario A_R: Run the model in scenario A but this time assume with the width of the river is 5 m and the elevation of the bottom of the sediments is 995 m. Compare the results with those in scenario A. What is the effect of reducing the width of the river