HR: 0800h
AN: H31C-1322    [Abstracts]
TI: Design and Testing of a Soil-Corer Air Permeameter
AU: * Chief, K D
EM: kchief@hwr.arizona.edu
AF: Hydrology and Water Resources University of Arizona, 1133 E. North Campus Drive, Tucson, AZ 85721-0011 United States
AU: Ferre, T P
EM: ty@hwr.arizona.edu
AF: Hydrology and Water Resources University of Arizona, 1133 E. North Campus Drive, Tucson, AZ 85721-0011 United States
AU: Nijssen, B
EM: nijssen@u.arizona.edu
AF: Hydrology and Water Resources University of Arizona, 1133 E. North Campus Drive, Tucson, AZ 85721-0011 United States
AU: Nijssen, B
EM: nijssen@u.arizona.edu
AF: Civil Engineering and Engineering Mechanics University of Arizona, P.O. Box 210072, CE Bldg, Room 206, Tucson, AZ 85721-0072 United States
AB: Measurements of air permeability are useful both directly, to assess gas phase movement through soils, and indirectly as a proxy for soil hydraulic conductivity. Several designs have been presented for field-based air permeameters. However, none of these designs are suitable for use in rocky soils, such as those found in the desert Southwest. We designed an air permeameter that is used with a standard soil corer to facilitate insertion into desert soils. The soil-corer air permeameter (SCAP) design employs digital components to measure flowrates under low-pressure gradients in order to improve accuracy and ease in reading. By virtue of its design, SCAP also allows for the extraction of undisturbed soil samples for laboratory analysis, allowing for direct comparisons of in-situ air permeability with other soil physical and hydraulic properties. Finally, for cohesive soils, the soil sample can be extracted before testing, thus removing the need for shape factors to account for divergent flow. We show coupled measurements of in-situ and ex-situ air permeability, soil hydraulic conductivity, particle size distribution, and gravimetric water content measured in four field soils under varying conditions. Results demonstrate the dependence of air permeability on these soil properties and point to possible limitations in the use of approximate shape factors when interpreting air permeameability measurements.
DE: 1830 Groundwater/surface water interaction
DE: 1866 Soil moisture
DE: 1875 Vadose zone
SC: Hydrology [H]
MN: Fall Meeting 2005