2007 Ground Water Summit

Wednesday, May 2, 2007 : 9:00 a.m.

Transient Heterogeneity Below the Water Table and Effects on Contaminant Plumes

J. F. Devlin, Ph.D.1, P.C. Schillig1, M.A. McGlashan1, G.P. Tsoflias1 and Douglas M. Mackay2, (1)University of Kansas, (2)University of California Davis

The response of flow and transport to changing permeability over time has been studied for many years with regard to two phase flow in the unsaturated zone.  However, the conceptual model for contaminant transport below the water table is generally that it occurs through a medium with hydraulic conductivity that varies in space but not in time.  Experiences over the past decade with remediation schemes, such as reactive barriers, air sparging, and some biobarriers, have shown that transient heterogeneity can occur below the water table.  More recent field experiments indicate that transient heterogeneity may also occur in naturally attenuating plumes.  The nature and causes of this heterogeneity are such that conventional methods of characterization may not be appropriate and/or sufficient.  New tools, such as the point velocity probe used in conjunction with ground penetrating radar, may offer insights into these processes.

J. F. Devlin, Ph.D., University of Kansas J.F. Devlin is an Associate Professor in the Dept. of Geology at the University of Kansas. His research interests include the relationship of permeability to reactivity of contaminants in groundwater, aquifer characterization, and granular iron performance in permeable reactive barriers.

P.C. Schillig, University of Kansas P. Schillig is a M.Sc. student in the Dept. of Geology at the University of Kansas. His research is concerned with the development and application of a point velocity probe for monitoring transient heterogeneity in a petroleum hydrocarbon plume.

M.A. McGlashan, University of Kansas M. McGlashan is a M.Sc. student in the Dept. of Geology at the University of Kansas. His research is concerned with the application of borehole ground penetrating radar to evaluate aquifer variations due to microbial activity in a hydrocarbon plume.

G.P. Tsoflias, University of Kansas G.P. Tsoflias is an Assistant Professor in the Dept. of Geology at the University of Kansas. His research interests include the application of geophysical techniques to geological and hydrogeological problems including the characterization of fracture networks and porous media.

Douglas M. Mackay, University of California Davis D.M. Mackay is an Adjunct Professor in the Department of Land, Air & Water Resources at the University of California Davis. His research interests include the fate, transport, natural attenuation, and remediation of organic contaminants in groundwater.


The 2007 Ground Water Summit