1. Lecture Leaky aquifers

2. Review problem At time t=0 well A started pumping QA= 2 cfs. Well B started one day later with the same Q. Estimate the time at which both wells contribute equally to the drawdown at the observation well. 400 ft 100 ft AB o.w.

3. Review problems An aquifer test conducted in a confined aquifer intersected by a no flow boundary (unknown location) suggested that the drawdown at an observation well 200 ft from the pumping well after 250 minutes to be 16 ft, instead it was 18 ft. Estimate the distance from the well to the boundary. At 10 minutes the drawdown was 2 ft and it was assumed that the influence of the boundary at that early time is negligible,

4. Governing equation Consider shown volume element

6. Steady radial flow in leaky aquifer The solution is given by: Modified Bessel Function of second kind of order zero

8. Transient case leaky aquifer W(u,beta) Hantush well function Solution GPDA:

9. Hantush well function