It is important to simulate a groundwater transport process, e.g., pollutant migration, through the vadose zone and subsequent mixing within the saturated zone to assess potential impacts of contaminants in the subsurface in preliminary stages. It is challenging to simulate heterogeneous soil characteristics and non-uniform initial contaminant concentration. This paper proposes a vertically het...

To gain an integrated understanding of flow and transport in the vadose zone and its role in transmitting conA vadose zone flow and transport model for Los Alamos Canyon tamination to the regional aquifer, conceptual flow and is presented that demonstrates that a comprehensive understanding transport models must be combined with site-specific of vadose zone hydrologic processes can be obtained ...

A physically based, variably saturated flow model was developed to predict soil water dynamics, evapotranspiration (ET) from the vadose zone, and recharge to (or exfiltration from) the saturated zone using mean daily atmospheric forcings and to identify the value of diurnal climate forcings on those predictions. The vadose zone flow is modelled using the Galerkin finite element technique to sol...

[1] We explore the mechanisms whereby groundwater influences terrestrial water storage (TWS) in the Amazon using GRACE observations and two contrasting versions of the LEAF-Hydro-Flood hydrological model: one with and the other without an interactive groundwater. We find that, first, where the water table is shallow as in northwestern Amazonia and floodplains elsewhere, subsurface stores (vados...

Surfactant-based foam delivery technology has been studied to remediate Hanford 200 area deep vadose zone sediment. However, the surfactants and remediation amendments have an unknown effect on indigenous subsurface microorganisms. Microbial populations are important factors to consider in remediation efforts due to their potential to alter soil geochemistry. This project focuses on measuring m...

background: groundwater nitrate pollution is an important environmental problem in water resources management. in this regard, specific measures aiming at prevention of water pollution will be helpful to managers and decision-makers. identification of aquifers’ vulnerable areas and determination of groundwater protection zones using most widely used models, such as drastic and cd, are one of th...

In this study we investigate the effect of a water table boundary on solute spreading during infiltration in the vadose zone of heterogeneous soils. It has been found recently that the presence of the water table significantly affects unsaturated flow in a heterogeneous vadose zone and causes the flow to be spatially nonstationary. Because a vadose zone is by definition bounded by the water tab...

s and Presentations: Jardine, P.M. 1999. Fate and Transport of Radionuclides Beneath the Hanford Tank-Farms: Unraveling Coupled Geochemical and Hydrological Processes in the Vadose Zone. Workshop on Hanford Tank Farm Needs, Environmental Management Science Program, Pacific Northwest National Laboratory. October, 1999, Richland, WA. Jardine, P.M., S.C. Brooks, S.E. Fendorf, C.C. Ainsworth, and B...