TALK ABSTRACT Science is a living document; it grows and expands as more information becomes available and our knowledge grows. It makes use of hypothesis, experiments, observations, and measurements. Groundwater scientists have a difficult task. They work in a system that is not visible, and they cannot take it into a laboratory to study. They use geophysical methods and drill boreholes to get an idea of the groundwater system that they are studying. These become the building blocks – the puzzle pieces – that are used to develop the conceptual model. This is the hypothesis of the groundwater scientists. Fortunately, there is never a completely right or completely wrong conceptual model, as it depends on the information that is available and the quality thereof. The puzzle pieces that make up the conceptual model vary in size and importance. There are large puzzle pieces that are often easy to collect and fit together, while it is more costly and time consuming to collect the small puzzle pieces. When starting with a groundwater study, there ae some pieces of information that may already be available, depending on the work that has been done in the area before. These may include maps, reports, hydrocensus information, drilling information, water level measurements, and water quality information. Additional information that may prove useful in the development of a conceptual model may be land use, vegetation, information on soil types and climate date. Anecdotal information from people that know the area well can prove to be valuable at times. When you work in an area where little or no work has been done, you will have to collect most of the information. In a study area where there is a large amount of information available, it will be necessary to sort through it and it is often necessary to cut through the clutter to get the most relevant information.

The West Coast aquifer system was used as a case study to illustrate the development of a conceptual model. Information about the site will be included with an emphasis on the geology and geohydrology of the study area. The water levels and water quality, as well as the role they played in the development of the conceptual model will be discussed. The conceptual model for the study area will then be presented in conclusion.