Objectives: Determine the impact of a now flow boundary on
groundwater pumping in a confined aquifer.
1. Groundwater drawdowns in wells can be impacted in aquifers that are adjacent to no flow boundaries, such as impermeable faults or even building foundations. These no flow boundaries cause an asymmetry in the cone of depression. In order to solve this style of problem, we can use image wells, which are imaginary wells that are added to the system to represent drawdown at the no flow boundary. The foldable aquifer model that is provided in the problem below asks you to solve one of these drawdown problems, where the pumping well is adjacent a no flow boundary. Before pumping there is no gradient across the confined aquifer as shown by the dashed line. Use the foldable aquifer model provided to answer the following question
A. Determine the pumping rate at the well needed to cause the confined limestone aquifer to become unconfined adjacent to the fault.
B. Once the confined limestone aquifer becomes unconfined adjacent to the fault what is the direction of groundwater flow. If you were to then turn the pumping well off how would this direction of groundwater flow change.
C. If the fault was replaced by a lake of infinite volume what would the pumping rate would be needed to cause the limestone aquifer to become unconfined.
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