Landfill site selection in Islamabad using Fuzzy-AHP and its Environmental Impact Assessment

Abstract

Landfill site selection is a multifaceted practice which needs to include various diverse criteria. The objectives of this study was to select a landfill site using multi criteria decision support system in GIS and evaluate environmental impact assessment (EIA) of the selected site. Islamabad, capital city of Pakistan was selected as a study site. Eleven criteria were selected which include roads, railway, airport, ground water table depth, geology, soil texture, precipitation, slope, surface water, waterways and faults. The Analytical Hierarchical Process (AHP) and Buckley’s fuzzy-AHP methods were used in a GIS. Criteria weights were calculated using AHP in Weighted overlay tool, which resulted in identification of eight possible landfill sites. These eight sites were assessed in Fuzzy-AHP against other non-quantifiable parameters (transportation issues, public nuisance, economic factors, land use, environmental impact and available vehicles) involving expert opinion. On the final site, EIA was carried out as per the guidelines of United Nations Environmental Program (UNEP). The result of this research illustrates the importance of the weights in identification of criteria for selecting the optimum location of landfill site i.e. near G-16, Islamabad. The area of selected landfill site is about 234 hectares and is 12.3 km away from existing dumping site in I-12. This process is useful in identifying dumping sites for cities where best landfill areas are occupied by urban sprawl.