Research on Fluid Flow and Chemical Transport in the Vadose Zone and the Partially Saturated Fringe

Inducing Fluid Flow and Chemical Transport in the Vadose Zone

Our most recent work involves inducing horizontal flow in the vadose zone by taking advantage of natural capillary barriers in combination with suction cup lysimeters to allow both injection and withdrawal of fluid into fine sediment lenses (within coarser sediment matrices). This work is being pursued through both laboratory and numerical experiments.

Suction cup lysimeters

Time-lapse movie of tracer (green dye) movement through a fine

(30-40 mesh) sand surrounded by coarse (12-20 mesh) sand. Note the

lack of migration of green dye into the underlying coarse sand

(approximately 3 megabytes).

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Fluid Flow, Chemical Transport and Microbial Activity in the Zone of Transition Between the Vadose Zone and the Region Below the Water Table

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Experiments on Entrapment of Air and LNAPLs in the Vicinity of the Water Table:

This work focused on laboratory and numerical studies of entrapment of air or

LNAPLs in the vicinity of the water table during drainage and imbibition. The

upper photo shows the general tank set up (with TDR probes used to measure

saturation percentages) with the lower photo showing the entrapment of

SOLTROL (dyed red) during imbibition with water.

See the Master’s thesis and Ph.D. dissertation of Dr. Andrea Dunn

as well as publications (info below) for details on this work.

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Work With Microbial Transport Through The Capillary Fringe: See Papers Below

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Our Early Experiments (in collaboration with the Weismann Institute of Science, Rehovot, Israel)

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Related Publications

Dunn, A.M., S.E. Silliman, S. Dhamwichukorn, and C.F. Kulpa, “Demonstration of Microbial Transport into the Capillary Fringe via Advection from Below the Water Table”, Journal of Hydrology, 306(1-4), 50-58, 2005.

Dunn, Andrea M., Air and LNAPL entrapment in the partially saturated fringe laboratory and numerical investigations, PhD Dissertation, University of Notre Dame, Notre Dame, Indiana, 105 pp., 2005.

Berkowitz, B., S.E. Silliman and A.M. Dunn, “Impact of the capillary fringe on local flow, chemical migration, and microbiology”, Vadose Zone Journal, 3, 534-548, 2004.

Dunn, A., and S.E. Silliman, “Air and Water Entrapment in the Vicinity of the Water Table: A laboratory study on heterogeneous sands”, Ground Water, 41(6), 729-734, 2003.

Dunn, Andrea M., Air and water entrapment in the vicinity of the water table : a laboratory study on heterogeneous sands , Masters Thesis, University of Notre Dame, Notre Dame, Indiana, 65 pp., 2003.

Silliman, S.E., B. Berkowitz, J. Simunek, and M. th. van Genuchten, “Fluid Flow and Chemical Migration Within the Capillary Fringe”, Ground Water, 40(1), 76-84, 2002.