Application of GIS-based multi-criteria decision making analysis (GIS-MCDA) in selecting locations most suitable for siting engineered landfills – the case of Ashanti Region, Ghana

Abstract

PurposeThe study aimed to use geographic information system (GIS) based multi-criteria decision making analysis (GIS-MCDA) to select areas suitable for siting landfills in Ashanti region. It also sought to ascertain variables most sensitive to the siting of landfill in the region.Design/methodology/approachThis study utilized GIS-based Multi-criteria decision making analysis –AHP to model and select areas most suitable to siting landfills within the region. Overall, 16 variables including wind speed and hydraulic conductivity (which were previously neglected in landfill siting in Ghana) were identified through comprehensive literature review. These variables were weighted using AHP method and integrated using the weighted linear combination (WLC) in GIS environment to develop five sub-models: the physical environmental, sociocultural, economic/technical, climatic and hydrogeological sub-models. These sub-models were further weighted and then integrated to derive the final suitability model.FindingsResults show that 13% (3,067 km2) of the region was identified as most suitable to siting engineered landfills. The study also identified 11 sites which are considered most suitable for situating landfills. On a sensitivity angle, hydrogeological (R2 = 0.5923; p = 0.003) and physical environmental sub-model (R2 = 0.254; p = 0.034) significantly predicted the final suitability model developed.Practical implicationsGhana's Landfill Guidelines seeks to optimize site selection and ancillary services that culminate into achieving sanitary landfills by 2020. Evidence still abounds on the unsuitability of existing and in some cases, new landfill sites presenting environmental and social negative impacts. The comprehensive evaluation of most crucial variables – social and environmental factors that determine an optimal landfill location – will be of immense help to policy planners like the Environmental Protection Agency (EPA) towards upgraded landfills. The authors hope that, concerned agencies will adopt the model in the study and integrate into their existing landfill suitability modeling techniques to provide a more grounded framework that optimizes landfill site selection within the study area.Originality/valueThis study is the first attempt to consider a regional-level waste collection site selection in Ghana using comprehensive sets of social and environmental factors and will therefore contribute immensely to EPA's goal of achieving upgraded landfills by 2022.

A GIS-based multi-criteria evaluation of landfill site selection in the region of Hodna, Algeria

“…Sensitive ecosystems: The criterion of sensitive ecosystems has been given the same importance as the standard of surface water for the conservation of ecosystems, especially the wetlands represented by the Shatt al-Hadna, forests, green spaces, orchards and historical and archaeological areas. Accordingly, a 500-meter area has been placed around all sensitive ecosystems; places located at distances of less than 500 meters are not suitable, and places more than 3,000 meters are very suitable (Barakat et al, 2017;Dolui and Sarkar, 2021;Asori et al, 2022;Nanda et al, 2022) (Figure 4).…”

“…The landfill must be carried out in the ground with impermeable soil to avoid contamination of groundwater with succulents resulting from the decomposition and fermentation of organic waste (Asori et al, 2022) The principle of work of the landfill depends on the soil in the landfill, where the types of breeding in the study area are divided into 7 types, Clay or calcareous soils are preferred for poor permeability (Barakat et al, 2017;Sk et al, 2020) (Figure 5). Residential area: To avoid visual pollution and smell and affect the value of the land, future expansion and popular rejection, TLC should not be completed close to urban or residential centers; in this study 5 areas were adopted by placing a 500-meter area around all residential areas, places located at distances of less than 500 meters are not suitable and places more than 2,000 meters are very suitable (Babalola and Busu, 2011;Redjem et al, 2021) (Figure 6).…”

“…Distance from roads: Distance from roads is an important economic criterion in choosing the location of a landfill to facilitate and reduce the cost of transporting waste from the source urban agglomerations to TLC without forgetting that technical backfill centers have become investment projects at the level of which the process of sorting resilient waste (paper, plastic... etc) (Nascimento et al, 2020), Where in this study 5 areas were adopted by placing a field of 200 meters around all roads, where places located at distances of less than 200 meters are very suitable, and places more than 2000 meters are not suitable (Redjem et al, 2021) (Figure 12). Distance from railway track : Due to the presence of the railway line and passes through 9 neighboring municipalities from Barika in the east to M'sila in the west and its route along the national roads can be used to transport waste from the source of generation represented by urban centers to the treatment unit represented by the TLC, as well as exploited in the transport of materials resulting from recycling, to reduce pollution and the cost of transportation (Dolui and Sarkar, 2021), and even temporary waste warehouses can be completed around the railway line of each municipality, where in This study adopted 5 areas by placing a 500-meter area around the railway line, where places located at distances of less than 500 meters are very suitable and places more than 3,000 meters are suitable, extremely to avoid the smell and visual pollution (Barakat et al, 2017;Dolui and Sarkar, 2021;Asori et al, 2022;Nanda et al, 2022) (Figure 13).…”

“…Recently, there has been an increase in research that uses Geographic Information System (GIS) Combining at AHP application for analysis, evaluation and decision-making assistance (Barakat et al, 2017;Bilgilioğlu and Bilgilioğlu, 2017;Alkaradaghi et al, 2020;Osra and Kajjumba, 2020;Sisay et al, 2021;Ahire et al, 2022;Asori et al, 2022). Studies such as Sharholy et al (2007), Sumathi et al (2008), andMohammedshum et al (2014) described the role of GIS and AHP in solid waste management.…”