HR: 11:00h
AN: H22C-03 INVITED     [Abstracts]
TI: Prediction of down-gradient impacts of DNAPL source depletion using tracer techniques: Laboratory and modeling validation
AU: * Jawitz, J W
EM: jawitz@ufl.edu
AF: University of Florida, 2169 McCarty Hall, Gainesville, FL 32611, United States
AU: Basu, N
EM: nbasu@ufl.edu
AF: University of Florida, 2169 McCarty Hall, Gainesville, FL 32611, United States
AU: Chen, X
EM: xiaosong@ufl.edu
AF: University of Florida, 2169 McCarty Hall, Gainesville, FL 32611, United States
AB: Interwell application of coupled nonreactive and reactive tracers through aquifer contaminant source zones enables quantitative characterization of aquifer heterogeneity and contaminant architecture. Parameters obtained from tracer tests are presented here in a Lagrangian framework that can be used to predict the dissolution of nonaqueous phase liquid (NAPL) contaminants. Nonreactive tracers are commonly used to provide information about travel time distributions in hydrologic systems. Reactive tracers have more recently been introduced as a tool to quantify the amount of NAPL contaminant present within the tracer swept volume. Our group has extended reactive tracer techniques to also characterize NAPL spatial distribution heterogeneity. By conceptualizing the flow field through an aquifer as a collection of streamtubes, the aquifer hydrodynamic heterogeneities may be characterized by a nonreactive tracer travel time distribution, and NAPL spatial distribution heterogeneity may be similarly described using reactive travel time distributions. The combined statistics of these distributions are used to derive a simple analytical solution for contaminant dissolution. This analytical solution, and the tracer techniques used for its parameterization, were validated both numerically and experimentally. Illustrative applications are presented from numerical simulations using the multiphase flow and transport simulator UTCHEM, and laboratory experiments of surfactant-enhanced NAPL remediation in two-dimensional flow chambers.
DE: 1831 Groundwater quality
DE: 1832 Groundwater transport
SC: Hydrology [H]
MN: 2007 Joint Assembly