GIS-based decision support approach for selecting a new landfill site for the city of Cape Town

Includes bibliographical references (leaves 107-111).Recent studies indicate that the population of Cape Town generates approximately 2.2 milliontons of waste annually. Numerous waste minimization strategies have been developed whichhave not been successful in reducing the amount that needs to be disposed of at a landfill site.This results to mounting pressure on existing waste disposal sites thus necessitating an urgentneed for a new regional landfill. According to CCA Draft Environmental Impact Report (2006),the former Cape Metropolitan Council (CMC) appointed technical consultants in 2000 to identifyand assess the potential sites for a landfill to service Cape Metropolitan Area (CMA), presentlyreferred to as the City of Cape Town (CCT). The construction of a landfill has significant impacts on the environments. It is for that reason Integrated Environmental Management (IEM) has to be followed to assess the impacts. The principle of IEM is broadly interpreted as applying to the planning, assessment, implementation and management of any project proposal or activity that has a potentially significant effect on the environment. Environmental Impact Assessment (EIA) process, which lies in the heart of the IEM, is enforced to examine the environmental effects of development. These impacts are directly related to the physical location of the project. That makes site selection for proposed project a very important stage of the EIA process. Laws have been enacted to minimizeenvironmental impacts, including strict guidelines for siting landfills. Using landfill siting criteria and site selection methods, the technical consultants identified four potential sites, Atlantis being the only site falling within the City of Cape Town. The interviews, backed by secondary data sources such as websites and project reports, revealed that the techniques used to identify potential sites for the landfill, even when combined are costly and time consuming. Several scenarios were run using various ArcGIS extensions, including the ModelBuilder to identify sites that met the stated criteria. GIS analysis yielded agreeable results with the recommendations from the consultants who used techniques other than GIS to identify the regional landfill. The research findings demonstrate that GIS is an efficient and dependable stand-alone technique that can be implemented in landfill site studies thus expedite the decision making process