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 ...

[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...

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...

At the regional scale, vadose-zone processes are recognized for controlling both short-term dynamics in watershed hydrology and long-term water balances of hydrologic basins. In this paper we explore the various conceptual and mathematical models that have been proposed or could be considered to represent water fluxes in the vadose zone at the catchment, watershed or regional scale. Such models...

Functionally, the methods for addressing contamination must remove and/or reduce transport or toxicity of contaminants. This problem is particularly challenging in arid environments where the vadose zone can be up to hundreds of feet thick, rendering transitional excavation methods exceedingly costly and ineffective. Delivery of remedial amendments is one of the most challenging and critical as...