A two-region nonequilibrium model for solute transport in solution conduits in karstic aquifers
Files
Download Full Text
Publication Date
August 2000
Abstract
A two-region nonequilibrium model was used to calibrate initial solute-transport parameter estimates generated from tracer-breakthrough curves (TBCs) developed from tracer tests conducted in uni-axial solution conduits in karstic aquifers. Two-region nonequilibrium models account for partitioning of solute into mobile- and immobile-fluid regions to produce a more representative model fit to the strong tails associated with TBCs than do equilibrium models. The nonequilibrium model resulted in an increase in average flow velocities and a decrease in longitudinal dispersion coefficients over comparable estimates using an equilibrium model. Increases in velocity and decreases in dispersion were obtained at the expense of including parameters that describe solute partitioning and mass transfer rate for the mobile- and immobile-fluid regions. In addition, nonidentifiable sorption and mass transfer parameters for the immobile-fluid regions could only be described in terms of upper and lower bounds using readily determined identifiable ratios representing solute partitioning and system constraints based on known physical properties. The identifiable ratios and system constraints serve to minimize model nonuniqueness and renders the nonidentification problem trivial.
Keywords
Karstic Aquifers, Solution Conduits, Nonequilibrium Modeling, Velocity, Longitudinal Dispersion
Document Type
Article
Notes
Journal of Contaminant Hydrology, Vol. 44, no. 3-4 (2000-08-01).
Identifier
SFS0055950_00001
Recommended Citation
Fielda, Malcolm S. and Pinsky, Paul F ., "A two-region nonequilibrium model for solute transport in solution conduits in karstic aquifers" (2000). KIP Articles. 5490.
https://digitalcommons.usf.edu/kip_articles/5490