[1] In this study, we directly derive first-order analytical solutions to the pressure head moments (mean and variance) for one-dimensional steady state unsaturated flow in randomly heterogeneous layered soil columns under various random boundary conditions. We assume that the constitutive relation between the unsaturated hydraulic conductivity and the pressure head follows an exponential model...

Groundwater flow in sedimentary rock saprolite, and in soils derived from this material, is strongly influenced by sedimentary layering and fractures inherited from the parent bedrock. The main objectives of this study were to determine whether parent bedrock lithology and infilling of fractures and other macropores with pedogenically derived clays and Fe/Mn oxides also play major roles in cont...

Environmental contamination with aircraft de-icing fluids (ADF) is becoming a concern. Propylene glycol (PG) composes the largest fraction of the ADF most commonly in use in the U.S. The biodegradation of PG and ADF in saturated and unsaturated sand columns was evaluated, in addition to the impact of biodegradation on the hydrodynamic characteristics of the porous media. In studies with unsatur...

[1] Flow diversion around subsurface cavities in unsaturated fractured media is important to numerous environmental and engineering applications. This paper provides analytical solutions to partial and complete flow diversion around cavities intersected by fractures under steady state conditions. It is focused on a typical trifracture junction located upstream from a cavity surface. Fractures a...

The parameter n in the well-known expression for hydraulic conductivity K ˆ K0S e (where K0 is its value at satiation and Se the e€ective saturation) is determined as a function of the exponent in the power form of the soil±water retention relationship. The result is validated with an extensive experimental database comprising some 43 soils, collected by Mualem. Ó 2000 Elsevier Science Ltd. All...

Critical path analysis and percolation theory are known to predict accurately dc and low frequency ac electrical conductivity in strongly heterogeneous solids, and have some applications in statistics. Much of this work is dedicated to review the current state of these theories. Application to heterogeneous porous media has been slower, though the concept of percolation was invented in that con...

Fractured-rock aquifers display spatially and temporally variable hydraulic conductivity generally attributed to variable fracture intensity and connectivity. Empirical evidence suggests fracture aperture and hydraulic conductivity are sensitive to in situ stress. This study investigates the sensitivity of fractured-rock hydraulic conductivity, groundwater flow paths, and advectiondominated tra...