Effects of soil heterogeneity have been the focus of both field and theoretical research for the past decade (e.g., Hills et al., 1991; Hopmans et al., 1988; Mantoglou and Gelhar, 1987; McCord et al., 1991, Russo, 1991; Ünlü et al., 1990; Wierenga et al., 1991; Yeh et al., 1985a,b; Yeh et al., 1986). Analytical models are essential tools for investigating the effect of heterogeneity on flow and...

We investigated the effect of different flow conditions on the transport of bacteriophage phiX174 in Memphis aquifer sand. Virus transport associated with a wetting front moving into an initially unsaturated horizontal sand column was experimentally compared with that observed under steady-state saturated vertical flow. Results obtained by sectioning the sand columns showthattotal (retained and...

Regional modeling of subsurface cadmium and zinc transport in a diffusely polluted area in the south of the Netherlands is the subject of this study. The atmospheric deposition of cadmium and zinc was caused by three zinc-ore smelters (point sources of emission). Agriculture and other sources of heavy metals are small compared to the atmospheric deposition in the vicinity of the smelters. A cou...

Groundwater and raw water pollution risks of pesticides were assessed by analyses of groundwater samples and by modelling groundwater flow and chemical transport with a coupled model ‘train’ consisting of: a regional Modflow model for simulation of groundwater flow in the saturated zone (IBRAHYM, TNO 2007)) a 1-D model for simulation of water and pesticide transport in the unsaturated zone (PEA...