Untangling Diffusion from Advection in Unsaturated Porous Media: Experimental Data, Modeling, and Parameter Uncertainty

  title={Untangling Diffusion from Advection in Unsaturated Porous Media: Experimental Data, Modeling, and Parameter Uncertainty},
  author={Philip H. Stauffer and Jasper A. Vrugt and H. J. Turin and Carl W. Gable and Wendy E. Soll},
  journal={Vadose Zone Journal},
  pages={510 - 522}
We conducted a series of experimental and modeling tests using data from the Busted Butte Unsaturated Zone Transport Test. First, we conducted a suite of reactive (e.g., Li), nonreactive (Br), and colloidal tracer experiments. These tracers were injected for 190 d from two point sources at rates of 1 and 8 mL/h, respectively. We then used a numerical simulator (FEHM), populated with laboratory‐measured hydrologic properties, to verify that our conceptual model of the tracer test yielded a good… 

Quantifying Transport Uncertainty in Unsaturated Rock using Monte Carlo Sampling of Retention Curves

We have developed a new Monte Carlo sampling method for simulating flow and transport in unsaturated porous media, characterized by van Genuchten–Mualem constitutive relations. Instead of sampling

Not All Mass Transfer Rate Coefficients Are Created Equal

This commentary attempts to clarify the confusion resulting from the different definitions of the mass transfer rate coefficient and discuss their implications for model applications in physical transport in soils and aquifers with preferential flow paths and relative flow barriers.

Impact of a Porosity-Dependent Retention Function on Simulations of Porous Flow

AbstractNumerical models of flow in unsaturated porous media employ a range of functions to account for capillary effects. In general, these retention functions are assigned at the beginning of the

Transport by Oscillatory Flow in Soils with Rate‐Limited Mass Transfer: 1. Theory

Oscillatory flow of fluid in a porous medium can generate a one‐way transport of heat or chemicals if there is a gradient of temperature or chemical concentration and a rate‐limited heat or mass

Thermo-Hydro-Mechanical Coupled Modeling of In-Situ Behavior of the Full-Scale Heating Test in the Callovo-Oxfordian Claystone

Within the context for deep geological disposal (DGD) of high-level radioactive waste (HLW), thermo-hydro-mechanical (THM) coupled numerical modeling has become significantly important for studying

Vadose Zone Transport of Tritium and Nitrate under Ponded Water Conditions

Vadose zone transport of tritium and nitrate can be important considerations at radioactive waste sites, landfills, or areas with industrial impacts. These contaminants are of particular concern

Uncertainty in Prediction of Radionuclide Gas Migration from Underground Nuclear Explosions

Underground nuclear explosions (UNEs) produce radionuclide gases that may seep to the surface over weeks to months. The objective of this research was to quantify the impact of uncertainties in

UZIG USGS Research: Advances through Interdisciplinary Interaction

Because vadose zone research relates to diverse disciplines, applications, and modes of research, collaboration across traditional operational and topical divisions is especially likely to yield

Heat‐Generating Nuclear Waste in Salt: Field Testing and Simulation

A field‐scale experiment and numerical simulations confirm salt backfill behavior. Simulations closely match temperature around and under the piled salt backfill. Results indicate limited



Inverse Modeling of Subsurface Flow and Transport Properties: A Review with New Developments

Many of the parameters in subsurface flow and transport models cannot be estimated directly at the scale of interest, but can only be derived through inverse modeling. During this process, the

Modeling unsaturated flow and transport processes at the Busted Butte Field Test Site, Nevada.

Inverse Modeling of Subsurface Flow and Transport Properties Using Recent Advances in Global Optimization, Parallel Computing and Sequential Data Assimilation

Faced with the complexity and spatial variability of the subsurface, and the difficulty of performing controlled experiments, a variety of numerical simulation models have been developed to predict

Vadose Zone Transport of 1,1,1‐Trichloroethane: Conceptual Model Validation through Numerical Simulation

A conceptual model is developed to better understand vadose zone vapor‐phase diffusion within the mesas of the Pajarito Plateau at Los Alamos National Laboratory. We focus on 1,1,1‐trichloroethane

Toward Improved Identifiability of Soil Hydraulic Parameters

We present a thorough identifiability analysis of the soil hydraulic parameters in the parametric models of Brooks and Corey (BC; Brooks and Corey, 1964), Mualem–van Genuchten (VG; van Genuchten,

Toward Improved Identifiability of Soil Hydraulic Parameters: On the Selection of a Suitable Parametric Model

We present a thorough identifiability analysis of the soil hydraulic parameters in the parametric models of Brooks and Corey (BC; Brooks and Corey, 1964), Mualem–van Genuchten (VG; van Genuchten,

Multiphase, Multicomponent Parameter Estimation for Liquid and Vapor Fluxes in Deep Arid Systems Using Hydrologic Data and Natural Environmental Tracers

Multiphase, multicomponent numerical models of long‐term unsaturated‐zone liquid and vapor movement were created for a thick alluvial basin at the Nevada Test Site to predict present‐day liquid and

Surface Water–Groundwater Connection at the Los Alamos Canyon Weir Site: Part 2. Modeling of Tracer Test Results

Field observations of bromide transport in the unsaturated zone are used to constrain simulations that provide estimates of bulk porosity and permeability for the Cerros del Rio. The Cerros del Rio