Estimates of ground‐water velocity, based either on Darcy's law or on the single‐well drift and pumpback tracer method, require prior knowledge of effective porosity. That is, after field data have been collected, the equation for ground‐water velocity, using either method, still contains the two unknowns, velocity and porosity. If the local hydraulic gradient is known and if a drift and pumpback tracer test is conducted at a well whose hydraulic conductivity has been determined, two independent functional relationships between velocity and porosity are established. By treating these functions as nonlinear simultaneous equations, a unique solution for the local velocity and porosity can be obtained.
No takes yet. Share an insight, caveat, or question.
Hall et al. (1991) studied this question.
Synapse has enriched one closely related paper. Consider it for comparative context: