Most cities in developing countries are fast industrialising, leading to an increased hazardous waste generation. Though disposal occupies the bottom of the waste management hierarchy, it is an important component of the waste management chain, requiring greater focus to mitigate its environmental and human health effects. The selection of a hazardous waste landfill site is a complex decision-making process since it requires the consideration of several laws and regulations and the integration of various data. This study presents a multi-criteria decision analysis for selecting hazardous waste landfill sites in Western Ghana. Thirty-two evaluation criteria arranged according to four hierarchy levels were selected for the study. The selected criteria considered geo-environmental, economic and social factors. Twenty-one intermediate suitability maps were created, which were then aggregated to produce a composite landfill suitability map of the study area. To narrow down the search for space for landfill sites, optimality criteria were applied on the composite suitable map to select the best locations for landfill. The application of the optimality criteria led to the selection of 5% of the study area as optimal for landfill sites. However, the final decision for landfill site selection will require further in situ studies. Overall, this research provides a proven landfill site selection methodology, which provides essential support for decision-makers.
Keywords: Hazardous waste; hierarchy model; landfill; multi-criteria decision analysis; selection criteria; suitability index.