I used a 3D model to simulate how much water should be pumped out from each well (totally I used 11 wells as a first trial) to intercept contaminant from a dam. I set a pump rate of 720 m3/day for each well as a first trial. I used minimum hydraulic head constraint for each well. After the model is run, I checked rate budget and found that the outflow rate from well is 10^9 m3/day. How does this unreasonable number happen? I appreciate any help.

Quinn