A Lesson From Production Analysis
The rapid depletion of the high permeability layer(s) implies that the deliverability of the well will diminish with time. Thus, contractual agreements made on the basis of short duration tests will not be met. If the commingled layers consist of one high permeability layer while all the others are low permeability, then the test will only give the kh of the high permeability layer. Time to reach pseudo-steady state can be diagnostic - longer if there is no crossflow (from injection test).