Correct Response: C. The fault in the granite can be a source of recharge for the medium sand aquifer because geologic faults often contain water under pressure that can flow upward into an overlying aquifer. Although it is hard to predict whether a particular fault will provide substantial recharge for an aquifer, faults are often an important source of recharge in a variety of geologic settings. Shale (A) and granite (D) typically have poor hydraulic conductivity and are an unlikely source of significant recharge for the medium sand aquifer. Since the stream (B) is separated from the confined medium sand aquifer, it could not be a direct source of water for that aquifer.
