Without
the well, a "doughnut" shaped flow field will occur with flow inward on the
perimeter of the top layer and downward in the center then outward on the perimeter
of the lower layer.
Head contours in the upper layer would be generally concentric
and decreasing from 990 at the edge and dropping to nearly 985 in the center
while in the lower layer are generally concentric and decreasing from about
985 in the center and dropping to 980 at the perimeter.
The transient of the flow field moving from a uniform
head of 990 in the upper layer and 980 in the lower layer to this doughnut shaped
flow field will progress along with the transient pumping.
The magnitude of the two transients will vary
depending on the pumping rate and the material properties. The pumping rate
could be large enough to reverse the flow patterns.