HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hunt, A. G. Articles by Gee, G. W. Search for Related Content PubMed Articles by Hunt, A. G. Articles by Gee, G. W. GeoRef GeoRef Citation Agricola Articles by Hunt, A. G. Articles by Gee, G. W. Related Collections Hydraulic Conductivity Structure and Properties Soil Hydrology

Water-Retention of Fractal Soil Models Using Continuum Percolation Theory

Tests of Hanford Site Soils

^a CIRES, Box 216, University of Colorado, Boulder, CO 80309-0216
^b Hydrology Group, P.O. Box 999, Pacific Northwest National Laboratory, 3200 Q. St., Richland, WA 99352-0999

View larger version (17K): [in a new window]   Fig. 1. Experimental data for the particle size distributions of seven representative soils.

View larger version (13K): [in a new window]   Fig. 2. Experimental data for the water-retention curves for the same seven soils as in Fig. 1 and comparison with theoretical calculations from assumed fractal geometry. Arrows denote the moisture contents, d, at which the experimental curves deviate from the predicted curves.

View larger version (25K): [in a new window]   Fig. 3. Plot of observed d vs. calculated SA0.52vol (with unknown proportionality constant A). The FLTF, VOC, and ITS soils are each denoted by an oval. The straight line fit through the origin is an approximate minimum value of d for a given SA0.52vol, and is, on account of its lack of a y-intercept, compatible with the Moldrup relation, Eq. [11], for the threshold moisture content for solute diffusion.

View larger version (23K): [in a new window]   Fig. 4. Plot of observed d vs. calculated R-0.052m, where Rm is the geometric mean of r0 and rm. Note that similar parameters are obtained by the linear regression as in Fig. 3, as well as the value of R2.

View larger version (21K): [in a new window]   Fig. 5. Plot of observed d vs. calculated SA0.52vol (excluding the FLTF soils). The same straight line, which bounded all the measurements, is reproduced on this graph, and that and the linear regression are solved simultaneously for the moisture content at which the two lines cross, = 0.12.

View larger version (15K): [in a new window]   Fig. 6. Predicted values of K(h), using experimentally determined values of threshold moisture content, air-entry pressure, and the first experimental head value at, or below, the deviation of h() from the fractal prediction. While the FLTF loams all have predicted K values above the minimum value for equilibration, roughly one-half of the sands or gravelly soils in the VOC and about one-third of those in the ITS regions are expected to have K values too low to equilibrate. Note that the "others" category denotes ERDF and B8814 loamy sands.

View larger version (24K): [in a new window]   Fig. 7. Simultaneous plots of predicted K(h) for Hanford site soils. The solid circles are the gravelly sands or sandy gravels, the open squares are sands, and the dashes are loams.