THE ROLE OF PREFERENTIAL FLOW AS A MECHANISM FOR GROUNDWATER CONTAMINATION I

Authors: HORTON, R - IOWA STATE UNIVERSITY; Jaynes, Dan; Logsdon, Sally; CASEY, F X - IOWA STATE UNIVERSITY; LEE, J H - IOWA STATE UNIVERSITY

Submitted to: American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: 5/29/1998
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Preferential flow has been observed during laboratory and field investigations with structured agricultural soils. Preferential flow poses a means for agrichemical contamination of groundwater. Therefore advance determination of preferential flow characteristics of field soil is important. We propose an in situ infiltration method for determining preferential flow characteristics. The method uses a ponded or tension infiltrometer to apply a series of fluorobenzoate tracers to the soil. After infiltration is completed, soil samples are taken in order to determine tracer concentrations. Based upon tracer concentrations, the effective porosity, hydraulic properties, and chemical transport properties of the soil can be determined. The method has been applied to Iowa agricultural soils in both laboratory and field settings. Thus far the method has been able to characterize preferential flow properties of soil.