HR: 0830h
AN: H11D-0885    [PDF]
TI: Determination Of Transverse Dispersivities At Lab Scale: Conservative Transport And Steady State Reactive Plumes
AU: * Olsson, $ H
EM: asa.olsson@uni-tuebingen.de
AF: University of Tbingen, Center for Applied Geosciences, Sigwartstr. 10, D- 72076 Tbingen, Germany, Tuebingen, 72076 Germany
AU: Piepenbrink, M
AF: University of Tbingen, Center for Applied Geosciences, Sigwartstr. 10, D- 72076 Tbingen, Germany, Tuebingen, 72076 Germany
AU: Ptak, T
AF: University of Tbingen, Center for Applied Geosciences, Sigwartstr. 10, D- 72076 Tbingen, Germany, Tuebingen, 72076 Germany
AU: Grathwohl, P
AF: University of Tbingen, Center for Applied Geosciences, Sigwartstr. 10, D- 72076 Tbingen, Germany, Tuebingen, 72076 Germany
AB: Effective remediation of contaminated ground water by Natural Attenuation relies on the ability to predict and quantify the processes that occur in contaminant plumes. Transverse mixing is a significant mechanism for the fluxes of electron acceptors and donors and thus may control the lengths of steady state plumes. Especially reactive mixing, which is governed by pore-scale processes, must be well understood at the local scale. This work aims to systematically investigate the influence of aquifer material properties, e.g grain sizes, grain size distributions, porosity, and variation in ground water flow velocity on the magnitude of the transverse mixing in saturated porous media. The dispersion of a conservative tracer was determined by measuring the distribution of fluorescein plumes at the outlet of a 2D flow-through tank. The dispersion values of the respective steady state plumes were evaluated by fitting the Gaussian (normal) distribution to the measured fluorescein data points. Steady state reactive plumes have been created in the tank using two different instantaneous bimolecular reactions. A complexation between copper(II) ions and EDTA and an acid/base reaction using HCl and NaOH were chosen on account of their fast reaction kinetics. The influence of flow velocity, concentration ratio and grain size on the length of the steady state plumes have been investigated for these reactions.
DE: 1615 Biogeochemical processes (4805)
DE: 1832 Groundwater transport
SC: Hydrology [H]
MN: 2003 Fall Meeting