ABSTRACT
Numerical models have become irreplaceable tools used in the struggle to solve groundwater pollution problems. Despite modelcodes becoming more and more sophisticated, the modelling process is heavily subject to errors. The Groundwater Modelling Module (GMM) is one of the Knowledge-Based Modules of a Decision Support System for Groundwater Pollution Assessment. The groundwater modelling process consists of several steps that are associated with particular modelling tasks. The groundwater model calculates state variables and their distribution which are, in most cases, the main outcomes of the modelling process. During the Model Design the initial values of state variables should be entered into the model. Calibration is a process of refining the numerical model to achieve a desired degree of correspondence between the model simulations and observations of the groundwater flow system. The Model Complexity Module is seen as an example of encapsulation of rule-based knowledge in groundwater quality modelling. The GMM consists of several software applications developed in various programming environments.
