HR: 1330h
AN: H43C-05    [Abstracts]
TI: Protocol for Quantifying a Solute Mass Flux in Shallow Groundwater
AU: * Gish, T J
EM: tgish@hydrolab.arsusda.gov
AF: USDA-ARS Hydrology & Remote Sensing Lab., Building 007, Room 104, Beltsville MD, MD 20705
AU: Kung, K S
AF: Department of Soil Science, University of Wisconsin, Madison, WI 53706
AU: Daughtry, C T
AF: Department of Agricultural and Biological Engineering, Cornell University, Ithaca, NY 14853
AU: Steenhuis, T S
AF: Department of Agronomy, Purdue University, West Lafayette, IN 47906
AU: Kladivko, E J
AF: Department of Agronomy, Purdue University, West Lafayette, IN 47906
AU: Nicholson, T J
AF: Nuclear Regulatory Commission, Mail Stop T-9C34, Washington, DC 20555
AU: Cady, R E
EM: REC2.twf5_po.TWFN_DO@nrc.gov
AF: Nuclear Regulatory Commission, Mail Stop T-9C34, Washington, DC 20555
AB: Field solute transport studies inferring the relevance of matrix and preferential flow processes are common but actual flux measurements quantifying their impact are essentially nonexistent. To fully understand solute transport and develop theory to describe their behavior and impact, it is crucial to first quantitatively determine a total solute flux, including when preferential flow becomes active. As a result, to quantify a total solute flux leaching from matrix and preferential flow processes must be simultaneously monitored. A protocol extending a flux method previously developed for tile-drained systems was tested for shallow ground water systems without a tile drain. A bromide flux was monitored that represented a treated soil area of about 30 m2, which was subsequently subjected to a 4.1 mm/h irrigation rate. Results indicated that: 1) over 98 percent of the applied bromide tracer was recovered; 2) at 4.1 mm/h over half of the surface-applied bromide was recovered at a depth of 1.6 m after only 280 mm of irrigation; and 3) at this location, bromide fluxes were dominated by preferential flow when subjected to a 4.1 mm/h irrigation rate. Preliminary results suggest this protocol may be a useful tool for quantifying solute transport fluxes in non tile-drained systems.
DE: 1829 Groundwater hydrology
DE: 1831 Groundwater quality
DE: 1832 Groundwater transport
DE: 1875 Unsaturated zone
SC: Hydrology [H]
MN: 2005 Joint Assembly