Unmodified versions of common computer programs such as MODFLOW, MT3DMS, and SEAWAT that use Cartesian geometry can accurately simulate axially symmetric ground water flow and solute transport. Axisymmetric flow and transport are simulated by adjusting several input parameters to account for the increase in flow area with radial distance from the injection or extraction well. Logarithmic weight...

This study presents an integrated modeling system for the evaluation of quantity and quality water resources coastal agricultural watersheds. The consists coupled interrelated models, including (i) a surface hydrology model (UTHBAL), (ii) groundwater (MODFLOW), (iii) crop growth/nitrate leaching (REPIC, R-ArcGIS-based EPIC model), (iv) contaminant transport (MT3DMS), (v) seawater intrusion (SEA...

SEAWAT is a finite-difference computer code designed to simulate coupled variabledensity ground water flow and solute transport. This paper describes a new version of SEAWAT that adds the ability to simultaneously model energy and solute transport. This is necessary for simulating the transport of heat and salinity in coastal aquifers for example. This work extends the equation of state for flu...

Perfluorooctanoic acid (PFOA) has been detected in environmental samples in Ohio and West Virginia near the Washington Works Plant in Parkersburg, West Virginia. This paper describes retrospective fate and transport modeling of PFOA concentrations in local air, surface water, groundwater, and six municipal water systems based on estimates of historic emission rates from the facility, physicoche...

By coupling two commonly used computer programs, MODFLOW (McDonald and Harbaugh, 1988) and MT3Dms (Zheng and Wang, 1998), the SEAWAT program was developed to simulate variable-density, transient ground-water flow in three dimensions. Freshwater head and salt concentration are used as the two principal dependent variables. Major improvements from the previous version of SEAWAT include (1) reform...

[1] Hyporheic exchange is an ecologically important process, controlling the nutrient supply in the upper sediments and thus benthic habitat quality. Hydraulic exchange at a riffle-pool sequence in the Lahn River, Germany, was analyzed using HEC-RAS to simulate the surface water flow as a boundary for the subsurface flow and MODFLOW, MODPATH, and MT3DMS to reproduce the transport in the subsurf...

This article examines the required spatial discretization perpendicular to the fracture-matrix interface (FMI) for numerical simulation of solute transport in discretely fractured porous media. The discrete-fracture, finite-element model HydroGeoSphere (Therrien et al. 2005) and a discrete-fracture implementation of MT3DMS (Zheng 1990) were used to model solute transport in a single fracture, a...

Groundwater flow and transport predictions are a major component of remedial action evaluations for contaminated groundwater at the Savannah River Site. Because all groundwater modeling results are subject to uncertainty from various causes; quantification of the level of uncertainty in the modeling predictions is beneficial to project decision makers. Complex site-specific models present formi...