GIS- and MCD-based suitability assessment for optimized location of solid waste landfills in Dar es Salaam, Tanzania

Site suitability analysis for sanitary landfills using geospatial methods in a part of southern Peninsular Malaysia

Globally, around 1.3 billion tonnes of waste are generated annually, and solid waste management has thus become a major concern worldwide. There are projections of a 70% increase in waste generation from 2016 to 2050 owing to urbanization and the rapid growth of the global population. Estimates indicate that around 38,200 tonnes of waste are generated per day in Malaysia, and this volume of waste is significantly shortening the planned life spans of operating sanitary landfills in the country. Batu Pahat is a district in the state of Johor, Malaysia, with a relatively large population of 495,000 and with no record of an operational sanitary landfill. This study was conducted to identify and classify the most suitable sites for sanitary landfill developments in southern Peninsular Malaysia by means of the Analytical Hierarchy Process (AHP), which is recognized as a competent technique for multicriteria decision-making. The resulting landfill site suitability index map established 33.88 km2 of area coverage as very highly suitable for landfill development, while 353.86 km2 of area coverage was classified as unsuitable. Sites 1-6 were identified as the most suitable for landfill activities. Sites 1-5 are situated in agricultural land areas, while site 6 is in a forested land area; this implies public participation and the adoption of compensatory measures in the event of landfill development in these areas, given their socioeconomic importance. The six suitable sites are all at least 2000 m from rivers: 2000-3000 m for sites 1, 3, and 5 and > 3000 m for sites 2, 4, and 6. The six sites are all > 3000 m from fault zones and > 1000 m from flood-prone areas, meaning that occurrences such as fault movements and flooding will have minimal impact on the operational activities of landfills at these sites. The selection of sites 1-6 as very suitable for landfill development was associated with an overall accuracy rating of 93.33% and kappa coefficient score of 0.92 based on accuracy assessment analysis of all sites. This study will guide the actions of policymakers, city planners, and local authorities toward sustainable and environment-friendly landfill development and operation in Batu Pahat and other districts in the state of Johor.

Self-reported symptoms of ocular allergy and its comorbid factors among residents living near a landfill site in Ghana

Residents close to landfill sites may be exposed to long-term emitted toxic compounds that may have effects on their eyes. The aim of this study was to determine the prevalence of symptomatic ocular allergy and its comorbid factors among residents living near a landfill site in Ghana. An exploratory cross-sectional design involving 400 inhabitants living around a landfill site was employed. The prevalence of symptomatic ocular allergy was 59.3%. In a bivariate analysis, comorbid conditions including respiratory disease, coughing, flu, cholera, skin disease, diarrhoea, and hypertension predicted symptomatic ocular allergy. However, only cholera remained a significant predictor of symptomatic ocular allergy in the multivariate analysis. Symptomatic ocular allergy was high among inhabitants around the landfill site in Ghana. While proper design and management of landfills in Ghana is crucial, further longitudinal and clinical studies are required to clinically establish the link between landfill and ocular allergy.

Sanitary municipal landfill site selection by integration of GIS and multi-criteria techniques for environmental sustainability in Safita area, Tartous governorate, Syria

Urban waste disposal is a problem that poses a major challenge to city planners as a result of rapid population growth and urbanization. Finding suitable sites for solid waste is one of the most important solutions developed globally to manage this problem. In this regard, a set of physical, socio-economic and technological criteria must be considered to tackle the problem. Safita area (Tartous governorate) witnessed a rapid population growth during the decade of the war in Syria due to the onrush of internal refugees, which resulted in several environmental problems, including random waste dumps. After perusing the previous literature and considering expert opinions, a map of the spatial suitability of sustainable waste sites in the Safita area was developed by integrating the multi-criteria decision- making methodology (analytic hierarchy process) with the geographic information system. Thirteen criteria, including elevation, slope, permeability, distance to faults, distance to settlement, land use/land cover, distance to drainage, distance to water supplies, distance to lakes, distance to road, distance from tourist centers, distance from archaeological centers, and distance from religious centers, were used to achieve the goal of this study. The layer maps for these criteria were developed based on various data sources, including conventional and remote sensing data. Potential landfill sites were identified and divided into five categories: unsuitable (83.28%), less suitable (8.49%), moderately suitable (4.49%), highly suitable (2.57%), and very highly suitable (0.72%). The results of this study provide reliable spatial outputs that will help in suggesting new landfill sites that maintain environmental and socio-economic sustainability in the post-war phase. Moreover, the application of the methodology of this study can be generalized to the rest of the regions in Syria within the framework of the integrated management of the problem of random landfills.

A systemic review for measuring circular economy with multi-criteria methods

Determining the circularity of a system through a criteria and indicators approach has been the focus of research in many branches of science. In this way, this work aims to review multiple criteria decision-making (MCDM) methods employed for measuring circular economy (CE) indicators and CE aspects at different levels (micro, meso, and macro). For this purpose, a systematic literature review (SLR) was conducted in ISI Web of Science and Scopus databases. Further, the results summarized 22 MCDM techniques, 27 CE aspects, and 36 CE indicators The SLR provides a concept map highlighting the relation of the level of circularity implementation (subdivided into micro-, meso-, and macro-levels) and MCDM techniques and demonstrates the interaction between CE aspects and indicators. The review provides an outline as to how MCDM techniques can solve problems related to CE aspects and marks the relevance in the use of CE indicators to support circularity aspects and to construct criteria in the methodologies applied.

A GIS-based novel approach for suitable sanitary landfill site selection using integrated fuzzy analytic hierarchy process and machine learning algorithms

Disposal of waste without treatment is the least preferable way of sustainable solid waste management (SWM). But most cities in developing nations still use open dumps, causing negative impacts on the environment and human health. This study offered a novel approach for selecting landfill sites and sustainable SWM in Aligarh city, India. This was done through data collection, selecting models for criterion weighting, and validation. In order to prepare a landfill site suitability map, a geographic information system (GIS)-based ensemble fuzzy analytic hierarchy process-support vector machine (FAHP-SVM) and fuzzy analytic hierarchy process-random forest (FAHP-RF) models were implemented. Considering the previous studies and the study area characteristics, eighteen thematic layers were selected. The result revealed that land value; distance from residential roads, hospitals and clinics, and waste bins; and normalized difference built-up index (NDBI) have a fuzzy weight greater than 0.10, indicating significant factors. In contrast, land elevation, land slope, surface temperature, soil moisture index, normalized difference vegetation index (NDVI), and urban classification have a zero fuzzy weight, indicating these criteria have no importance. The result further revealed that FAHP-RF with an area under curve (AUC) value of 0.91 is the more accurate model than FAHP-SVM. According to the final weight-based overlay result, seven potential landfill sites were identified, out of which three were determined as most suitable by considering current land cover, public opinions, and environmental and economic concerns. This research proposed a zonal division model based on landfill sites location for sustainable SWM in Aligarh city. However, the findings may provide a guideline to the decision-makers and planners for optimal landfill site selection in other cities of developing countries.

Landfill siting for municipal solid waste using remote sensing and geographic information system integrated analytic hierarchy process and simple additive weighting methods from the point of view of a fast-growing metropolitan area in GAP area of Turkey

The site selection process for municipal solid wastes (MSW) plays an important role in environmental impact studies by allowing the use of environmental design criteria in city and country planning. This process also includes the subject of urban planning due to its impact on the economy, ecology, and environmental health of the region. Urban growth is a phenomenon that is difficult to stop or limit in line with environmental, social, and economic changes and development. Therefore, the selection of solid waste landfill is of great importance in terms of ensuring a sustainable urban future. In the study, Landsat 5 and Landsat 8 satellite images, base map, soil, and geology maps were used for the integration of geospatial data. Each layer specified in the map has been formed using the spatial analysis potential of the ArcGIS10.5 software. In these digitized layers, weight scoring was made using the comparison matrix and the final suitability map was produced. All digital layers established in the generated maps were arranged according to the analytical hierarchy method (AHP) and subjected to the simple additive weighting (SAW) method. The results indicated that 13.51% of the total area was suitable for a sanitary landfill. As a result of this study, urban growth, population projection, and domestic solid waste volume of Sanliurfa province were determined. According to the 25-year population projection, the population in 2045 was approximately 4,471,938 people, and the cumulative waste volume was 27,415,627 m³. In addition, as a result of accepting the wastes of three metropolitan districts and seven district municipalities to the sanitary landfill, only "first candidate area" is the most and has been deemed appropriate. Given the ecological and environmental challenges (proximity to the city center, etc.) associated with the existing MSW sanitary landfill facility in Sanliurfa, the results of this study show that the geographic information system (GIS) integrated AHP and SAW method is an effective tool to assist decision makers to properly plan towards achieving a sustainable environment.

A multi-stage fuzzy decision-making framework to evaluate the appropriate wastewater treatment system: a case study

Selection of appropriate treatment processes for wastewater treatment (WWT) plants at the design stage involves a careful examination of different economic, environmental, and social parameters. Designers and decision-makers seek a compromise among such conflicting elements, which can be facilitated by decision support tools that are adapted for the ambiguity of individual opinions and decision parameters. This study aims to improve the qualification and efficiency of decision-making in WWT processes. A multi-stage framework is proposed to help select investments, technology, appropriate technology-specific system, and companies that apply such systems. The framework combines the Analytic Hierarchy Process (AHP), Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE), cash flow analysis, and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) within fuzzy logic. The main contribution is the description and formation of an integrated framework to guide businesses and researchers for the evaluation of several WWT decision processes. To the best of the authors' knowledge, no study in the literature fuses multiple stages of this WWT process with the proposed approaches.

An Integrated Multi-Approach to Environmental Monitoring of a Self-Burning Coal Waste Pile: The São Pedro da Cova Mine (Porto, Portugal) Study Case

The São Pedro da Cova waste pile (Porto, Portugal) is composed of coal mining residues that have been self-burning since 2005 and is located close to an inhabited area and social infrastructures, further adding to effects on the environment and human health. Therefore, there is a great interest in the environmental monitoring of this waste pile. This work describes an integrative multi-approach that allows the environmental monitoring of several parameters of the waste pile, applying several technologies. The temperature measurements were obtained by a thermal infrared (TIR) sensor on board an unmanned aerial vehicle (UAV) and supplemented with field measurements. In order to evaluate the altimetric variations, for each flight, a digital elevation model (DEM) was generated considering a multispectral sensor also on board the UAV. The hydrogeochemical characterization was performed through the analysis of groundwater and surface water samples, with and without the influence of mine drainage. The soil monitoring included the analysis of waste material as well as the surface soil in the surrounding area of the waste pile. All the data were analyzed and integrated in a geographical information system (GIS) open-source application. The adopted multi-approach methodology, given its intrinsic interdisciplinary character, has proven to be an effective way of encompassing the complexity of this type of environmental problem.