Argus Open Numerical Environments
   A family of general purpose public-domain graphical pre- and post-processors for the numerical modeler, combining GIS and numerical modeling. Includes plug-in extensions for the most widely used groundwater models, including
   http://www.argusint.com/index.html

BOSS International Groundwater Modeling Products
   Offers GMS, FEFLOW, and other groundwater software programs. Also has products for hydraulics and surface water hydrology.
   http://www.bossintl.com/html/groundwater_modeling_products.html

Discerning Systems Inc.
   Hydrogeochemical exploratory and statistical tools for analysis and management of monitoring data at landfills and industrial facilities.
   http://www.discerningsystems.com/

EasySolve Software LLC
   Offers low-priced software for environmental and earth science professionals -- create boring logs, calculate hydraulic conductivity, create variogram plots.
   http://www.easysolve.com/

Ecoseal Developments Pty Ltd
   Provides software, groundwater monitoring equipment, and magnetic instruments for environmental, agriculture, mining and education sectors.
   http://www.ecoseal.com/

Environmental Insite
   3d groundwater visualization application for analysis and communication of environmental groundwater data. Capabilities include mapping, 2d/3d contouring, pie charts, time history charting, radial diagrams and database queries.
   http://www.enviroinsite.com/

Environmental Simulations, Inc.
   Groundwater modeling software, services, and training, including sales and technical support for WinFlow, WinTran, MODFLOW-Win32, Groundwater Vistas, and AquiferWin32.
   http://www.groundwatermodels.com/

FEFLOW
   A finite-element simulation package for 3D and 2D density-dependent flow, mass and heat transport processes in groundwater and in the unsaturated soil. Description, pricing, and downloadable demo, from WASY Ltd.
   http://www.feflow.info/

GroundwaterSoftware.com
   Purchase groundwater software now and download immediately at discounted prices. Many applications available: flow and transport modeling, slope stability analysis, landfill design, and geostatistics.
   http://www.groundwatersoftware.com/

HydroBioGeoChem 123D
   For simulation of coupled non-isothermal (i.e., includes heat transfer equations) hydrologic transport and biogeochemical kinetic and/or equilibrium reactions in variably saturated media. 1-, 2-, or 3-dimensional.
   http://hbgc.esd.ornl.gov/

HydroSOLVE, Inc.
   Developer of software tools for groundwater modeling and aquifer test analysis.
   http://www.aqtesolv.com/

Hydrus-2D
   A software package for simulating two-dimensional movement of water, heat, and multiple solutes in variably saturated media.
   http://www.pc-progress.cz/Fr_Hydrus.htm

IGWMC Groundwater Modeling Software
   International Ground-Water Modeling Center distributes a large number of practical, public domain and proprietary ground-water programs, ranging from codes based on simple analytical solutions to those incorporating advanced and complex numerical techni
   http://typhoon.mines.edu/software/

MODFLOW and related programs
   USGS's popular modular 3D finite-difference ground-water flow model, plus pre-processors, post-processors, and adaptations for contaminant transport, and air flow.
   http://water.usgs.gov/nrp/gwsoftware/modflow.html

MicroFEM Groundwater Flow Modeling
   Offers several programs for applications including multiple-aquifer steady-state and transient flow, aquifer test analysis, and interpretation of geo-electrical measurements with Schlumberger or Wenner configurations. Downloads available.
   http://www.microfem.com/

Reaction-Transport Modeling In Ground-Water Systems
   USGS aqueous geochemistry codes, including PHREEQ (Speciation, Reaction-Path, Advective Transport, and Inverse Geochemical Calculations) and NETPATH (Interactive Code For Modeling Net Geochemical Reactions Along a Flow Path).
   http://wwwbrr.cr.usgs.gov/projects/GWC_coupled/

The MODFLOW help file
   Resources for users of the USGS-developed MODFLOW groundwater flow modeling package: online/downloadable tutorial, reference guide, lists of online MODFLOW resources vendors, and examples of input files.
   http://www.mindspring.com/~rbwinston/modhelp.htm

Triwaco
   Describes and offers a modular software package for modelling three-dimensional density-dependent groundwater flow, contaminant transport, and visualisation. Supports both finite element (Flairs) and finite difference (ModFlow) calculation methods.
   http://www.triwaco.com/

USGS Ground-Water Software
   Computer codes designed to model various ground-water and related hydrologic and geochemical processes and to help estimate related parameters.
   http://water.usgs.gov/software/ground_water.html

WASY Ltd.
   Firm based in Germany offers groundwater simulation software and related training and support, as well as consulting in groundwater monitoring, management, and protection, surface water management and hydrology. Describes capabilities.
   http://www.wasy.de/english/

Waterloo Hydrogeologic
   Develops and sells groundwater and environmental software for groundwater modeling, subsurface visualization, pumping test analysis, geochemistry, and natural attenuation and risk assessment. Products include Visual MODFLOW, AquiferTest, Visual Grou
   http://www.waterloohydrogeologic.com/

mView Numeric Modeling Support System
   Visual pre- and post-processor for groundwater modeling, supporting numerous modeling codes including TOUGH, FEHM, NUFT, ASHPLUME, WAPDEG, MODFLOW/MODPATH, FRAC3DVS and SWIFT.
   http://www.interaeng.ca/tech_mview.htm