Landfill site selection in hilly terrains: An integrated RS-GIS approach with AHP and VIKOR

This paper presents a novel integrated Geographic Information System-Multi-Criteria Decision Making (GIS-MCDM) framework for evaluating landfill site suitability in Shimla, India, a rapidly urbanizing hill station. Combining Remote Sensing-Geographic Information Systems (RS-GIS) with the Analytical Hierarchy Process (AHP) and VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) methods, the framework developed a Landfill Suitability Zoning map and ranked potential sites. The Land Suitability Index (LSI), derived using AHP, categorized the 124 sq. km study area into five suitability classes, with key factors influencing rankings: Landslide Proximity (weight: 0.162), Ground Slope (0.138), Land Use and Cover (0.122), Ground Elevation (0.114), and Road Proximity (0.095). From the Very High suitability zones, eight candidate sites were identified and ranked using VIKOR, with Kiargiri (score: 0.083) identified as the most suitable, followed by Baboloo (0.530), Karog (0.535), and Phayal Road (0.663). Sensitivity Analysis (SA) was conducted across five scenarios to account for possible variations in expert judgment, with the first three increasing beneficial weights (10 %, 15 %, and 20 %) and the last two decreasing beneficial weights (15 % and 20 %), proportionally adjusting non-beneficial weights. The SA confirmed the consistency and robustness of the rankings, with Kiargiri (0.083), Baboloo (0.530), Karog (0.535), and Phayal Road (0.663) maintaining top positions despite varying weight configurations. This approach offers a reliable, adaptable framework for landfill site selection in hilly urban areas, supporting waste management, sustainable development and environmental conservation.