Modeling landfill site selection by multi-criteria decision making and fuzzy functions in GIS, case study: Shabestar, Iran

Landfilling is the most common method used for disposal of solid waste and selection of suitable landfill for municipal solid waste management is important part of urban planning. The aims of this paper are determining the constraints, criteria for landfill site selection according to present legislations in Iran, zoning potential of Shabestar city for construction of municipal landfill and selection of the most suitable sites. At first, by reviewing of internal and external literature, the criteria which were necessary to achieve the aims of study were determined. Then, conceptual model of landfill site selection steps and process was developed. After that, the required maps were collected from relevant organizations and prepared using geographic information systems (GIS) tool in order to use in the next steps. Finally, all criteria maps were standardized by fuzzy functions and entered in mathematical combination model. In this study, the fuzzy functions in ArcGIS 10 including linear, large, small and Gaussian were used. Weighting of criteria was performed by analytical hierarchy process (AHP) method using expert choice application and weighted linear combination (WLC) was chosen for integration of maps. Preliminary results of zoning showed that nearly 6.2 % of the study area has good suitability for municipal landfill. To select the best site among the candidate sites for Shabestar city, at first the sensitive analysis was performed and then the best site was selected based on required area, soil depth, dominant wind direction and visibility from residential area.