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Urban environments, especially metropolitan places like Dessie with a high population, result in an increased output of waste. Waste pickers have collected the solid waste from the main road and the immediate area for truck dumping in the river downstream to Kombolcha town, all of these waste materials were deposed, and open burned in the final destination. The best way to deal with this issue is to find a proper waste disposal location in the area as the aim of the paper. To be justified, although, a number of previous related studies have been conducted with their main focus on the physical parameter to identify landfill suitability sites. In this study, not only consider the physical parameters but, also socio-economic parameters were considered, and it is still crucial to generate site-specific information. As a result, by choosing acceptable waste disposal sites using geospatial technology, the study has been undertaken to address the issues of environmental deterioration and the spread of infectious illnesses that are caused by incorrect garbage dumping and open burning in the City. A mixed research design was employed for this research. Since all the data used were processed through the application of software and formulas to produce the result in the map and numerical values which needs a detailed narration. Land use, land cover, slope, drainage, places of worship, groundwater wells, schools, soil, urban core, and population were taken into consideration. These elements were examined in terms of their parametric compatibility. To create a study waste suitability map using geospatial technology, all of the parametric appropriateness was weighted in the overlay analysis according to their respective values, which were obtained from the analytical hierarchal process (AHP). The categories included unsuitable, less suitable, moderately suitable, suitable, and highly suitable. Approximately 71% of the research area was unsuitable for the disposal of solid waste, while the remaining 29% was suitable for the disposal of solid waste concerning drainage, the weighted suitability map shows unsuitable areas were 40.8%, less-suitable areas were 17.6%, moderately suitable areas were 10%, suitable areas were 13%, and highly suitable areas were 18.6%. Existing potentially appropriate and highly suited waste disposal sites were located away from built-up, urban centers, religious institutions, and schools where high population pressure to reduce the detrimental influence on the environment and human health. Therefore, the study results strongly suggested that the current waste treatment area should be avoided and planted in highly suitable and suitable areas.

Cities worldwide have different sizes and development levels. The approach to store the wastes produced in different cities may vary depending on the size and development level of the specific region. In this study, municipal solid waste (MSW) characteristics for three income groups (low-, medium-, and high-income) in a region with a high level of development but low population density were examined. The MSW values pertaining to summer and winter months were analyzed. The results were used to predict the amount of electricity that could be generated from the landfill gas. The organic fraction of the MSW was 52.31%, and paper and cardboard, among other materials, occupied 19.63% of this fraction. The summer and winter distributions for the organic fraction were 34.33% and 30.38%, respectively. A total of 3.67 kW/t MSW of electricity could be generated. [ABSTRACT FROM AUTHOR]

Surface water and groundwater have been experiencing increasing risks of contamination in recent years because of the poor management of the immense amounts of waste created by different human activities. Inappropriate dump sites have served for many years as marginal disposal sites for a wide range of wastes, including solid waste, fresh sewage and hazardous waste, in developing nations such as Ethiopia. Physical, anthropogenic and organic procedures continuously interact to deteriorate the waste. One of the results of these practices is artificially contaminated leachate, which is potentially hazardous waste from disposal sites. If not managed appropriately, such a dumping site can contaminate groundwater (through leachates) and surface water (through contaminant transport by flooding and groundwater movement). Along these lines, this study focuses on the applications of water quality index in the ground and surface water quality caused by the waste disposal site of Bahir Dar city within the Chilanchil Abay during the study period. Water testing was performed on five samples of surface water and six samples of groundwater in each month from 30th March (dry season) to 20th August (wet season). More than 13 water quality parameters, for example, pH, TDS, electrical conductivity, turbidity, temperature, dissolved oxygen (DO), TH, biochemical oxygen demand (BOD), chemical oxygen demand (COD), TC, NO3−, PO43−, Cr, Mn, and Pb contents, were examined in both ground and surface water. It was discovered that water quality status of the Chilanchil Abay watershed ranges from 15.87 to 36.6 for surface water and 42 to 46.2 for groundwater suggesting poor and marginal status for drinking water purpose. HIGHLIGHTS The study assesses and evaluates the groundwater quality of Chilanchil Abay watershed through the investigations of spatial and temporal variations of physico-chemical and bacteriological parameters.; This manuscript also evaluates the concentrations of the nutrients (phosphate and nitrate) in each borehole as compared to the standard values for drinking and irrigations.;

Waste disposal sites are a serious concern due to their potential contamination threat. Site characterizations are the basis for contamination remediation, among which borehole-based methods are time-consuming. This study aims to utilize time-domain induced polarization (TDIP) to constrain groundwater and soil organic contamination. Fourteen TDIP profiles were arranged using three acquisition methods at a disposal site contaminated with benzene. A data quality analysis was first conducted to overcome poor signals in high-salinity groundwater conditions. The TDIP results show that solid waste can be classified into two distinct types based on chargeability. The results of induced polarization measurements and X-ray fluorescence analysis proved the presence of metal substances causing high chargeability. The waste with metals was the benzene contamination source. Finally, we propose a procedure for the integration of geophysical and geochemical methods to delineate contaminated areas. A new roll-along survey protocol was developed to meet the needs of long-profile surveys of contaminated shallow groundwater and soil sites. [ABSTRACT FROM AUTHOR]

A total of 214 sampling sites of a hazardous waste disposal center were surveyed in a two-stage pollution investigation, including soil boreholes and groundwater monitoring wells. Results showed that chemical oxygen demand (COD) (4.00–2930.00 mg/L), fluoride (0.07–9.08 mg/L), chromium (0.12–1.20 μg/L), nickel (0.15–459.00 μg/L), lead (0.10–10.20 μg/L), cadmium (Cd) (0.05–16.40 μg/L), and beryllium (0.06–3.48 μg/L) were detected in groundwater samples. For soils, Cd in soil (78.7 mg/kg) exceeded the risk screening value (65 mg/kg) for soil contamination of the second type of development land (GB36600-2018), and there remained the risk of leakage in the landfill detection investigation. Then, a health risk assessment was carried out. Based on the definitions of the groundwater exposure pathway (HJ 25.3-2019) and the pollution investigation of groundwater, the carcinogenic and non-carcinogenic risks of groundwater were generally considered to be negligible. The carcinogenic risk and non-carcinogenic risk of the concerned pollutant in soil for risk assessment (Cd) under the condition of reutilization exceeded the corresponding acceptable levels (1E-06 and 1). The (non-)carcinogenic risk of Cd mainly came from oral intake of soil and inhalation of soil particles under two conditions of reutilization and non-utilization, so on-site workers and surrounding residents should be properly protected from the mouth and nose to minimize the intake of pollutants from the soil and soil particles. The area of soil contaminated by Cd was about 630.58 m2, and the amount of pollution was about 1261.16 m3. The heavy metal pollution was only distributed in the depth range of 0–2 m, and the suggested risk control value of soil pollutants under the condition of reutilization for Cd was 56 mg/kg. Based on different pollution characteristics of soil, groundwater, and the landfill, targeted control measures were proposed.

Collection of soil samples is labored, time-consuming and the determination of heavy metal concentrations in the laboratory are expensive. The aim of this study was to fix the functions, algorithms as well as optimization of methods for soft computing system such as ANFIS, SVM, and ANN based on their best performance. In this study, soil samples were collected from eighty five distinct locations in and around of a selected open disposal site at old Rajbandh, Khulna, Bangladesh at a depth 0-30 cm from the existing ground surface. In the laboratory, the concentration of heavy metals such as Pb, Cu, Ni, Zn, Co, Cd, As, Sc, Hg, Mn, Cr, Ti, Sb, Sr, V and Ba in soils were measured. The soft computing systems such as ANFIS, SVM, and ANN were implemented for the analysis of heavy metal concentrations in soil. The result reveals model with SCP, gaussmf, linear and hybrid was the best-fitted model of ANFIS. In addition, in SVM analysis, the model SVM-RBF with 15 folds was selected. In ANN, the model LT (Levenberg-Marqardt and Tansig functions) with neuron structure 2-10-1 was selected. The accuracy of the predicted results was checked based on the acceptable limits of prediction parameters such as R value, RMSE, MAPE, GRI and percentage recovery. The result demonstrates that ANFIS model was a reliable technique than that of other counterparts of SVM and ANN with the acceptable degree of robustness and accuracy. Therefore, the performance of soft computing systems may be expressed by the sequence of ANFIS > SVM > ANN. Here it can be noted that one can easily be computed the concentration of a particular heavy metal in soil by inserting GPS values (latitude and longitude) only in the developed rule viewer of ANFIS. [ABSTRACT FROM AUTHOR]

Safe disposal and storage of dredged sediments from severely polluted urban lakes is a big challenge to deal with. This paper deals with the importance of hydro-geophysical and groundwater modeling applications for characterizing appropriate and environmental safe site for storage and disposal of hazardous dredged sediment from Hussain Sagar Lake bed. One such disposal site is proposed at Gajularamaram village near Quthubullapur Mandal, Greater Hyderabad. The area is having predominantly exposed rocks of Peninsular Gneissic Complex (PGC) along with enclaves of schists and basic dykes. The geological singularities are the major concern for an environmentally protected construction of the landfill. Hydro-geophysical studies, such as Electrical Resistivity Tomography (ERT), water level monitoring and in situ soil infiltration tests carried out in and around the proposed waste disposal granite quarry site. In situ soil infiltration rate varied from 0.09 to 15.36 cm/hr. Besides, groundwater flow and mass transport model was conceptualized for predicting any seepages of leachate from these waste filled quarry pits. The results indicated that the existing abandoned granite quarry pits are suitable for disposal of hazardous lake bed sediment of Hussain Sagar Lake. Furthermore, few remedial measures were suggested for arresting lateral migration of leachate if any through quarry pits. [ABSTRACT FROM AUTHOR]

The study, using regression and ANOVA, assessed the extent to which waste disposal sites impact residential rental values. The research collected data from both secondary and primary sources using a mixed method cross sectional survey. The linear hedonic price model was adopted to suit the research objectives. A questionnaire survey, expert interviews and a field investigation were used to gather raw data. The study revealed that all the residential properties that were far away from the waste disposal sites had higher rental values between (GH¢1200–1680) than those that were close (GH¢600–720). Construction of an engineered landfill by the district assembly for the town was recommended. Also, real estate developers in the town should be more circumspect about the siting of their residential properties since most of the people were not willing to pay higher rent if buildings are close to a filthy area like a dump site, irrespective of the architectural designs. [ABSTRACT FROM AUTHOR]

A disastrous landslide occurred at the Hong'ao Waste Disposal Site in Shenzhen, China on December 20, 2015, involving a volume of 2.7 × 106 m3 of municipal solid waste (MSW) that travelled a distance of 700 to 800 m, covering an area of 3.8 × 105 m2 and caused 90 casualties. The geomorphological and geological characteristics of the waste disposal site were carefully examined and the landslide was classified as an extremely rapid flowslide. The major feature of the waste site was the basin-like structure with the bottom composed of low-permeable granite bedrock. Therefore, surface runoff could easily accumulate in the MSW due to the lack of drainage system, resulting in an increasing groundwater level. Laboratory tests, including physical characterization, Consolidation Isotropic Undrained (CIU) test and direct shear test were conducted to characterize the material properties of the MSW. Physical characterization indicated the MSW belongs to sandy silt, CIU tests indicated that static liquefaction was conducive to high-speed sliding. The direct shear test data were used to carry out numerical analysis of slope stability, in which the continuous rise in the groundwater level was taken into account. Numerical simulation showed that the pore water pressure induced by underground water seepage and gradual loading from the upper MSW placement aggravate the failure. Consequently, the main reason of the landslide could be concluded as follows: 1) the perched groundwater level due to a large upstream catchment area and the lack of drainage system; 2) the excess pore water pressure induced by static liquefaction played a significant role in its mobility. [ABSTRACT FROM AUTHOR]

The main focus of present study was to demonstrate the possible generation sources of metal contamination in soil. The only authorized waste disposal site at Rajbandh located at Khulna in Bangladesh. To this endeavors, total sixty soil samples were collected at a depth of 0-30 cm from the existing ground surface and the relevant metal elements of Al, As, Ba, Ca, Cd, Cr, Co, Cu, Fe, Hg, K, Mn, Na, Ni, Pb, Sb, Sc, Sr, Ti, V and Zn were measured through standard methods in laboratory. Desired results for normality test obtained from normal QQ plot using XLSTAT. Almost all the metal elements were normally distributed in both the seasons. Multivariate statistics such as Pearson’s correlation, principal component analysis (PCA) and agglomerative hierarchical clustering (AHC) were performed using XLSTAT to show the correlation between metal elements and their possible generation sources. Results of multivariate statistics revealed that almost all the metal elements were strongly correlated indicating same generation sources. In addition, results of PCA and AHC depicted that almost all the metal elements in soil derived from anthropogenic/human activities; least number of metal elements from natural sources as well as from both the natural and anthropogenic sources. Proper identification and control of possible generation sources of metal elements may reduce the threat of soil contamination due to metal elements in waste disposal site.

Various types of landfills pose a direct threat to groundwater. Polluted groundwater is characterized by significantly reduced electrical resistivity. Geophysical methods -- in particular DC-resistivity methods -- are sensitive to this physical parameter. Applying these methods can allow for a spatial assessment of the groundwater quality near the landfills. The key with that approach is to recognize the geoelectrical structure of an area prior to the existence of a landfill. This information will allow for a geoelectrical background, which would most likely be an image of the natural and uncontaminated study area. Subsequent measurements will be more effective due to the possibility of comparing the current state of the area to the original state. This paper presents an example of such a study. Here, the research area of interest was located in the vicinity of an inactive tailings disposal site. In order to assess the pollution of the groundwater, a vertical electrical sounding method was applied. The results of modern measurements were compared with those from the reinterpretation of the data obtained several decades ago. The selected geoelectrical method proved to be effective, allowing for the determination of the range of contaminated groundwater in regions that were not covered by traditional hydrogeological monitoring by a piezometer network. Repetition of vertical electrical sounding in the future will allow for tracking the displacement of pollution within the aquifer. [ABSTRACT FROM AUTHOR]

To improve rational reusing and recycling of construction wastes, we discussed the logistics network design problems of two kinds of building waste reduction systems-with or without on-site processing conditions. According to the functions and interrelations of all participants in the system, a logistics network model of reduction system was established to realize the sustainable development of economic, environmental and social dimensions. Taking Chengdu as the research object, the logistics network of building waste reduction was conducted with optimal reconstruction. Results showed that the total system cost was reduced after the construction waste reduction. The recycling ability of construction waste was increased to improve economic and environmental benefits of the whole system. On the contrary, the ability of construction waste resources and the economic and environmental benefits of the whole systema are positively correlated. [ABSTRACT FROM AUTHOR]

Occasionally, a selected site suitable for landfill construction is severely protested against by locals. This issue can cause the proposed landfill to be relocated to an environmentally sensitive area. The proposed Khon Kaen waste disposal site has been planned as an integrated municipal solid waste management system, although the site is situated in an environmentally sensitive area. A site assessment can guarantee the suitability of waste disposal construction, with procedures that aim to assess the potential of geological and hydrogeological characteristics, geological barriers, geotechnical properties of material for landfill construction and groundwater conditions for future monitoring of such facilities. The study area is located on foothills where no geohazard or seismic impacts have been recorded. The geology is composed of sandstone, siltstone, and mudstone bedrocks mostly overlain by unconsolidated sediments. The natural geological barriers are clay and regolith. The clay layer lies locally and is rather thin, at around 2−3 m thickness. The study area is situated in an area that is highly vulnerable to groundwater pollution. The distinct weaknesses of this site along the foothill are a prominent transport path of shallow flows; high groundwater fluctuation, especially during the rainy season; that it is a recharge area with a high fracture zone; and the high permeability of colluvium. The material characteristics in the site make it suitable for use as landfill cover and liner. Following compaction, the coefficient of permeability ranges from 1.2 × 10−7 to 7.1 × 10−7 cm/s, which is acceptably impervious.

Geosynthetic Clay Liners, GCLs, is a commonly material in the construction of composite bottom liner systems and cover systems for waste disposal sites. As periodic change of climate has some effect on the hydraulic performance of GCLs, the intrinsic mechanism and the trend of the change in hydraulic conductivity for GCLs under freeze-thaw and wet-dry cycling were reviewed in this paper. The changes in particles size and thickness of diffuse double layers primarily account for the changes in hydraulic conductivity of GCLs. Generally, the freeze-thaw cycling has relatively small effect on the hydraulic conductivity of GCLs. In contrast, the wet-dry cycling has significantly large impact on the hydraulic conductivity of GCLs. [ABSTRACT FROM AUTHOR]

Landfill is the oldest and the most common form of removal and disposal of waste, constituting the final disposal method of municipal solid waste (MSW). It is well known that the impact of MSW landfills can cause pollution of all environmental components. The negative environmental impact of landfills can be reduced by applying protection technologies and appropriate solid waste management technologies. The present study undertook monitoring of the Štěpánovice MSW landfill influence on the environment. The spatial characteristics of the area influenced by the landfill and the possible impact of leachate using phytotoxicity tests were carried out. The landfill itself is engineered, with bottom liner and leachate and landfill gas collection and treatment system. The landfill has not had any direct and significant influence on the surrounding environment and water quality so far. [ABSTRACT FROM AUTHOR]