Per- and polyfluoroalkyl substances (PFASs) are a heterogeneous group of persistent organic pollutants that have been detected in various environmental compartments around the globe. Emerging research has revealed preferential accumulation PFASs shallow soil horizons, particularly at sites impacted by firefighting activities, agricultural applications, atmospheric deposition. Once vadose zone, ...

steel porous plates. Various control options for the tension applied to these porous plates have been advocated. The composition and quantity of leachate as it moves down through The simplest being zero tension, where no capacity to the vadose zone is seldom measured directly because sampling in this unsaturated zone at the depths required has proven to be extremely exert a tension on the plate...

As geographical information systems (GIS) are increasingly being applied to surface and subsurface flow and transport modeling issues, it becomes important to more clearly define potential advantages and achievable objectives with this technology. This chapter describes an integrated conceptual framework for predicting basin-scale solute loading rates through and from the vadose zone. The appro...

No validated models in Europe are capable of simulating the environmental fate of pesticides under the specific conditions of rice fields. Rice water quality--vadose zone flow and transport (RICEWQ-VADOFT) is a model developed from the coupling of a surface runoff model (RICEWQ) and a vadose zone flow and transport model (VADOFT) for determining predicted environmental concentrations in paddy w...

The unsaturated soil hydraulic properties are often described using Mualem–van Genuchten (MVG) type analytical functions. Recent studies suggest several shortcomings of these functions near saturation, notably the lack of second-order continuity of the soil water retention function at saturation and the inability of the hydraulic conductivity function to account for macroporosity. We present a ...

In vadose zone modeling, parameter es mates and model predic ons are inherently uncertain, regardless of quality and quan ty of data used in model-data fusion. Accurate quan fi ca on of the uncertainty is necessary to design future data collec on for improving the predic ve capability of models. This study is focused on evalua ng predic ve performance of two commonly used methods of uncertainty...