By Dr. C. Wels

Over the last decade, great strides have been made in developing numerical models covering virtually all aspects of mining hydrogeology from traditional 2D seepage models to complex models simulating multi-phase flow and multi-species contaminant transport. This page provides an overview of the most common numerical models currently available, grouped according to subject and application.

Groundwater Flow & Seepage Models for Porous Media

Solute Transport Models for Porous Media

Groundwater Flow & Solute Transport Models for Fractured Rock

Mine Reflooding Models

Tailings Consolidation Models

Geochemical Equilibrium Speciation Models


ARD Production and Airflow Models

For many of the models described here, software has been developed to facilitate the model input and view model output. For an overview of these "pre-post processors" and other software tools related to mining hydrogeology refer to Software Tools.

Note: The listing of any particular model does not imply endorsement of this product or the authorized dealer by the author(s) of this website. Please contact Christoph Wels if you would like to add other numerical models not currently listed on this website.


Groundwater Flow & Seepage Models for Porous Media

1D Unsaturated Flow

One-dimensional unsaturated flow models simulate 1D (vertical) flow in the unsaturated zone. They are also referred to as "variably saturated" flow models if they can also simulate saturated flow. Their most common application in the context of mining is to assist in water balance studies (e.g. assessment of evaporation and/or infiltration into tailings, waste rock etc.) and the design and evaluation of "dry covers" (store & release; capillary barrier etc.).

List of available models:

Please click here to view recent publications illustrating applications of 1D infiltration models to mining. We invite you to submit other modeling case studies for presentation on this website.


2D Unsaturated Flow

Two-dimensional unsaturated flow models simulate 2D (cross-sectional and radial) flow in the unsaturated zone. They are also referred to as "variably saturated" flow models if they can also simulate saturated flow. Their traditional application in the context of mining has been the assessment of seepage from tailings dams and water dams. However, these models are also increasingly used to assess infiltration into mine waste on slopes and for the design and evaluation of "dry covers" (store & release; capillary barrier etc.) on a sloped surface.

List of available models:

Please click here to view recent publications illustrating applications of 2D seepage models to mining. We invite you to submit other modeling case studies for presentation on this website.

2D Saturated Flow

Two-dimensional saturated flow models simulate 2D (cross-sectional and radial) flow in the saturated zone. In the context of mining, these models have traditionally been used to assess seepage from a tailings dam or a water storage dam (where the influence of unsaturated flow can be ignored) and water inflow to an open pit and/or underground mine (where the flow system can be simplified into a 2D flow system). However, with the recent advances in computer memory and user-friendly software, even 2D flow problems are now commonly simulated using 3D saturated flow models (using a "2D option"), thus providing more flexibility to the user.

List of available models:

Please click here to view recent publications illustrating applications of 2D groundwater flow models to mining. We invite you to submit other modeling case studies for presentation on this website.


3D Saturated Flow

Three-dimensional saturated flow models are capable of simulating 3D groundwater flow in complex aquifer systems. The applications of these 3D models in mining projects include a.o. assessment of groundwater resources (for drinking & process water), prediction of mine dewatering and reflooding, plus assessment of environmental impacts of mining on the local aquifer system(s). In addition, 3D groundwater flow models are now more commonly employed to study complex seepage problems involving water storage and tailings dams as well as the design of contaminant control systems (e.g. slurry walls, pump & treat).

List of available models:

Please click here to view recent publications illustrating applications of 3D groundwater flow models to mining. We invite you to submit other modeling case studies for presentation on this website.

3D Unsaturated Flow

Three-dimensional unsaturated flow models have the same applications as their saturated counterparts, but are better equipped to model complex geology and geometry (faults, fractures, highly variable topography, mine adits).

List of available models:

We invite you to submit modeling case studies for presentation on this website.


Solute Transport Models for Porous Media

Solute Transport in Unsaturated Zone

Unsaturated solute transport models are typically integrated with 1D or 2D unsaturated flow models and simulate solute transport in the unsaturated zone in one or two dimensions. Some models are limited to the simulation of non-reactive ("conservative") solutes, while others are capable of simulating sorption/desorption, production and decay. Typical applications of these solute transport models in mining include assessment and prediction of contaminant transport in unsaturated mine waste (e.g. tailings and waste rock) and/or in the unsaturated zone underlying mine waste.

List of available models:

Please click here to view recent publications illustrating applications of solute transport models for the unsaturated zone to mining. We invite you to submit other modeling case studies for presentation on this website.


Solute Transport in Saturated Zone

Saturated solute transport models are typically integrated with 2D or 3D saturated flow models and simulate solute transport in the saturated zone in one, two or three dimensions. Some models are limited to the simulation of non-reactive ("conervative") solutes, while others are capable of simulating sorption/desorption, production and decay. Typical applications of these transport models in mining include prediction of contaminant plume migration in aquifers impacted by ARD seepage, impacts of reflooding of underground workings and/or open pit on groundwater quality and design of contaminant control systems for aquifer remediation.

List of available models:

Please click here to view recent publications illustrating applications of solute transport models for the unsaturated zone to mining. We invite you to submit other modeling case studies for presentation on this website.


Geochemical Multi-Species Transport Models

Geochemical, multi-species transport models simulate the simultaneous transport of a suite of reactive solutes, which may react with other and/or the solid phase (minerals, soils and/or bedrock). These models are capable of simulating a broad range of reactions (including speciation & complexation, dissolution/precipitation, redox etc.), thus providing considerable flexibility. The use of these sophisticated geochemical transport models in mining is just emerging. However, these models offer great potential in the study of acid rock drainage (within mine waste and receiving aquifers) as well as in the development of contaminant control strategies (e.g. reactive barriers).

List of available models:

  • MIN3P (developed by K. U. Mayer at the University of Waterloo)
  • MINTOX (developed by Murray Wunderly at the University of Waterloo)
  • RT3D (Batelle)
  • PHREEQE (USGS)
  • PHREEQM-2D (IGWMC)

Please click here to view recent publications illustrating applications of hydrogeochemical transport models to mining. We invite you to submit other modeling case studies for presentation on this website.


Groundwater Flow & Solute Transport Models for Fractured Rock

Several models are currently available to simulate groundwater flow and solute transport in fractured rock. These models are generally favoured over the use of porous media models if flow and transport occur predominantly along discrete structural features such fractures and/or faults. Most fracture transport models are capable of simulating the diffusive transport between a discrete fracture set and the porous rock matrix. The application of fracture flow & transport models to mining projects has been very limited, in part due to the complexity of the model and the lack of adequate input information (structural information and transport parameters). However, these models are expected to become more widely used with future advances in the integration of geological and mine mapping software and groundwater modeling software.

List of available models:

Please click here to view recent publications illustrating applications of flow & transport models in fractured rock to mining. We invite you to submit other modeling case studies for presentation on this website.


Mine Reflooding Models

Several models have been developed for the specific task of simulating the flooding of large underground mines and the associated rebound of the groundwater table. The main difference to the conventional groundwater flow models is the provision for turbulent flow in the large, man-made voids typical for underground mines. Several models have been developed to suit the scale of the underground mine (from a few hundred m2 to thousands of km2). Mine reflooding models are typically used to predict the timing and/or location of groundwater discharge after mine reflooding.

List of available models:

  • EPANET (EPA)
  • VSS-Net (R.Adams & P.L.Younger at University of Newcastle)
  • GRAM (J.M. Sherwood at University of Newcastle)

Please click here to view recent publications illustrating applications of mine reflooding models to mining. We invite you to submit other modeling case studies for presentation on this website.


Tailings Consolidation Models

Several models are available to simulate the consolidation of fine, compressible tailings during filling of the tailings impoundment and, subsequently, in response to drain-down and/or surcharge loading. Such consolidation models are used in the mining industry for the assessment of storage capacity of the tailings impoundment, as well as prediction of future settlement and quantity of tailings pore water discharge after closure.

List of available models:

Please click here to view recent publications illustrating applications of consolidation models to mining. We invite you to submit other modeling case studies for presentation on this website.


Geochemical Equilibrium Speciation Models

Geochemical equilibrium speciation models calculate the equilibrium mass distribution among dissolved species, adsorbed species, and multiple solid phases under a variety of conditions including a gas phase with constant partial pressures. These models are commonly used in mining-related projects to assist in geochemical characterization studies (including field and laboratory measurements), ARD prediction for mine waste and contaminant transport.

List of available models:

Please click here to view recent publications illustrating applications of geochemical equilibriation speciation models to mining. We invite you to submit other modeling case studies for presentation on this website.


ARD Production & Airflow Models

Several sophisticated multi-process models have been developed over the last decade which are capable of simulating ARD production in waste rock and heap leach piles. These models simulate the coupled processes of pyrite oxidation, multiphase fluid flow (water and water vapour), advective and diffusive air (and oxygen) movement and heat flow and transfer. These ARD production models are used in the mining industry to optimize heap leach operations, and to predict the onset (and control) of ARD in waste rock piles.

List of available models:

Please click here to view recent publications illustrating applications of geochemical equilibriation speciation models to mining. We invite you to submit other modeling case studies for presentation on this website.

For example applications of ARD production models to mining-related projects, please view the respective project descriptions on the RGC website under Modeling.