A LANDFILL SITE SELECTION PROCESS INCORPORATING GIS MODELLING

SUMMARY: A selection procedure for the location of landfill sites, combining GIS technologies with site investigation methodologies, is outlined. Development of the GIS model was driven by the need to identify sites with suitable geological barriers to reduce potential risks of groundwater contamination by landfill leachate and to establish a scientific, non-biased approach to landfill site selection in order to promote public confidence in the scientific basis and overall transparency of the site selection process. There are two stages to the process: 1. GIS stage, consisting of a primary, two step screen, leading to identification of target areas, followed by a secondary screen, involving more detailed local information and site-specific analysis, to identify individual sites; 2. Geotechnical evaluation, consisting of site investigation and laboratory assessment of the geotechnical characteristics of individual sites. The developed GIS model pertains only to the primary screening. On completion of the site selection procedure, individual sites should be graded on a scale of suitability, and ranked in order of preference. 1