|Lee, Jaehoon - IOWA STATE UNIVERSITY|
|Horton, Robert - IOWA STATE UNIVERSITY|
Submitted to: American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: July 23, 1996
Publication Date: N/A
Technical Abstract: Two-domain solute transport models have been successful in describing chemical movement over a wide range of conditions. In applying the model, the water filled pore space is divided into a mobile domain, where water and chemicals can move by advection, and an immobile domain, where water is stagnant and chemical movement is by diffusion alone. The model assumes first order exchange between domains represented by a transfer rate coefficient. A major difficulty in applying the two-domain transport model is estimating the required model values of immobile domain and transfer rate coefficient. We describe a technique that uses a sequential application of conservative, non-interacting anionic tracers to measure immobile domain and transfer rate coefficient. The technique is well suited for field use in conjunction with ponded or tension infiltrometers. Comparisons between this method and conventional curve-fitting methods for estimating model parameters using solute breakthrough curves are presented. The results are promising with reasonable agreement found between the two methods for several different soil columns.