GSFLOW is a new U.S. Geological Survey model for simulating ground-water/surface-water interactions. GSFLOW couples PRMS (the Precipitation Runoff Modeling System) to MODFLOW (the Modular Ground-Water Model) with modules for simulating flow and storage in unsaturated-zones, lakes, and streams. GSFLOW simulates infiltration, runoff generation, and lateral flow in temporarily saturated material (...

Numerical simulations of water ̄ow and solute transport were used to investigate the e€ect of the recharge (rain/irrigation) at the soil surface on solute spreading and breakthrough in a realistic, three-dimensional, heterogeneous, vadose zone±groundwater ̄ow system. Results of the analyses suggest that smaller recharge at the soil surface increases the relative variability in the response of t...

A lysimeter trench was established at the Gardermoen delta (50 km north of Oslo, Norway) to study the flow of water and transport and degradation of aromatic jet fuel components (toluene and o-xylene) in the undisturbed unsaturated zone. Site investigations with ground-penetrating radar revealed the presence of dipping sedimentary layers within the foreset unit. This study has shown that the fo...

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...

A semianalytical solution is presented for transient streaming potentials associated with flow to a pumping well in an unconfined aquifer, taking into account the effect of flow in the unsaturated zone above the water table. Flow in the unsaturated zone is modeled with a linearized form of Richards’ equation using an exponential model for soil moisture retention and unsaturated hydraulic conduc...

An understanding of gas transport in unsaturated media is important for evaluation of soil aeration or movement of O 2 from the atmosphere to the soil. Soil aeration is critical for plant root growth because roots generally cannot get enough O 2 from leaves. Evaluation of gas movement is also important for estimating transport of volatile and semivolatile organic compounds from contaminated sit...

0022-1694/$ see front matter 2012 Elsevier B.V. A http://dx.doi.org/10.1016/j.jhydrol.2012.09.048 ⇑ Corresponding author. Tel.: +86 2768775432; fax E-mail address: [email protected] (J. Yang). It is a long-lasting challenge in subsurface hydrologic modeling to develop numerically efficient algorithm for coupling unsaturated and saturated flow, especially in regional-scale modeling. In this stud...

The evolution, over periods of up to nine years, of tritium, nitrate and other pore-water profiles in the Chalk unsaturated zone at sites in three areas in Britain is presented and evaluated in terms of transport mechanisms. Etablissement des profils séquentiels des isotopes et des matières en solution dans le zone non saturée de la partie britannique de la couche de chaux Résumé On présente l'...

An experiment was conducted at a depressional (lowland) and an upland site in sandy soils to evaluate the effects of surface run-off on the transport of agricultural chemicals to ground water. Approximately 16.5 cm of water was applied to both sites during the experiment, representing a natural precipitation event with a recurrence interval of approximately 100 years. Run-off was quantified at ...