HR: 1330h
AN: H22C-0944    [PDF]
TI: Non Equilibrium Infiltration in Unsaturated Laboratory Soil Columns
AU: * Schafer, A L
EM: nsa@inel.gov
AF: Idaho National Engineering and Environmental Laboratory, P.O. Box 1625 M.S. 2107, Idaho Falls, Id 83415 United States
AB: During infiltration of water into initially dry soil columns non-equilibrium conditions were observed in the soil water potential and water content histories. These effects were manifested by: non-unique water potential - water content relationships as a function of time under steady infiltration; delayed equilibration of water content relative to that of water potential; overshoot of a steady-state water content and water potential following step increases or decreases in infiltration rate; and equilibrium scanning curves appearing to be infiltration-rate dependant. Observation of these effects in the laboratory requires accurate measurement of flow rate, water content and water potential. Results of these experiments suggest that rapid step increases in flow rate will not allow the dynamic effect to dissipate or true equilibrium to be achieved. Further, it is not clear that single-valued constitutive relationships can exist under simulated laboratory scale transient infiltration events which has profound implications on field scale prediction of water and contaminant monitoring and prediction.
DE: 1832 Groundwater transport
DE: 1866 Soil moisture
DE: 1875 Unsaturated zone
SC: Hydrology [H]
MN: 2003 Fall Meeting