by Peter B Oladeji, Adekunle Benjamin Oyedare, Taiwo Olusegun Ogunwale, Simeon Oyesoji Oyetola, Taofeek Adekola Basiru, Oluwaseun Femi Ogunrinola

Ind. Domest. Waste Manag. 2024, 4(1), pp 23-41; https://doi.org/10.53623/idwm.v4i1.422

34 views
Abstract The Oyo State Solid Waste Management Authority (OYSWMA) hired private waste operators (PWOs) because the government was unable to handle the increasing amounts of solid garbage that were being carelessly deposited in every corner of the metropolis. This study looked at the private garbage contractors' methods of operation, clientele, and difficulties in managing residential solid waste in Ibadan, Nigeria. In the three local government districts of the metropolis, a structured questionnaire was given to 21 private refuse operators and 250 homes. A few measures of service quality were employed to determine the method of operation and customer base. To interpret the gathered data, both descriptive and inferential statistics were employed. The findings showed that the factors that affected residents and operators of SWM the most were educational attainment, monthly income, building types, and occupation (n = 213, 85.2%; 164, 65.6%). Of the houses who enrolled for waste collection, between 201-300 (47.6%) and 100-200 (42.9%) utilized private waste contractors. Although the license specifies once per week, waste collection is inconsistent and typically occurs once every two weeks (52.4%); charges, on the other hand, are variable and exceed the established rates. Undue financial backing from the LGAs, impassable areas, incompatible law, poor advertisement and awareness, political influence, exorbitant leachate treatment fees, and poor health were among the operational issues confronted the private garbage operators. The elements that affect the way the private sector of SWM operates and attracts customers were found to be as follows: non-cooperation of residents (n = 8, 38.1%), poor nearness to buildings (n = 9, 42.9%), and the lax enforcement of hygiene regulations (n = 4, 19.0%). The report suggests that in order to provide residents in Ibadan Metropolis with high-quality services, private refuse operators should regularly monitor and oversee the collection of solid waste.[...] Read more. Full text

by Tajudeen Yahaya, Okeke Chidi, Sani Abdulrahman, Esther Oladele, Abdulrakib Abdulrahim, Yunusa Abdulganiyu, Abdulrazaq Izuafa

Ind. Domest. Waste Manag. 2024, 4(1), pp 1-13; https://doi.org/10.53623/idwm.v4i1.375

195 views
Abstract The most common and cost-effective waste disposal method is the dumpsite; however, leachate from dumpsites may percolate and compromise groundwater sources. This study evaluated the levels of heavy metals (lead, cadmium, chromium, copper, and arsenic), physicochemical parameters (pH, electrical conductivity, total dissolved solids, hardness, calcium, magnesium, and chloride), and microorganisms in borehole water samples obtained at distances of 50, 100, 200, and 400 meters from the Igando dumpsite in Lagos, Nigeria. The health hazards associated with the heavy metals were also calculated. Physicochemical analysis indicated that the water samples were acidic, with pH values ranging from 4.30±0.01 to 5.21±0.008. They contained levels of calcium (166.73±0.01 - 328.66±0.06 mg/l), magnesium (83.72±0.02 - 119.40±0.17 mg/l), hardness (416.01±0.11 mg/l - 820.00±1.63 mg/l), and chloride (20.07±0.02 - 120.90±0.81 mg/l) that exceeded the limits set by the World Health Organization. Heavy metal analysis showed that, in all locations, lead exceeded the permissible limits, cadmium exceeded the limits except for the 400-m location, and copper, chromium, and arsenic (except for the 50-m location) were within permissible limits. The average daily intake and hazard quotient of the heavy metals were both within recommended limits, but the carcinogenic risks of lead, cadmium, and copper in water collected at a distance of ≤100m exceeded the threshold. Microbiological examinations revealed non-permissible levels of bacteria at all locations, coliforms at the 400-m location, and fungi at the 50-m and 400-m locations. On average, the parameters significantly (p<0.05) increased in concentrations as the proximity to the dumpsite decreased. These findings indicate that borehole water is not suitable for drinking without treatment.[...] Read more. Full text

by Suman Kunwar

Ind. Domest. Waste Manag. 2024, 4(1), pp 14-22; https://doi.org/10.53623/idwm.v4i1.408

242 views
Abstract As the world continues to face the challenges of climate change, it is crucial to consider the environmental impact of the technologies we use. In this study, we investigate the performance and computational carbon emissions of various transfer learning models for garbage classification. We examine the MobileNet, ResNet50, ResNet101, and EfficientNetV2S and EfficientNetV2M models. Our findings indicate that the EfficientNetV2 family achieves the highest accuracy, recall, f1-score, and IoU values. However, the EfficientNetV2M model requires more time and produces higher carbon emissions. ResNet50 outperforms ResNet110 in terms of accuracy, recall, f1-score, and IoU, but it has a larger carbon footprint. We conclude that EfficientNetV2S is the most sustainable and accurate model with 96.41% accuracy. Our research highlights the significance of considering the ecological impact of machine learning models in garbage classification. [...] Read more. Full text

by Jian Chong Chiu, Paran Gani

Ind. Domest. Waste Manag. 2024, 4(1), pp 56-71; https://doi.org/10.53623/idwm.v4i1.444

33 views
Abstract Soil pollution caused by heavy metals from anthropogenic activities poses a significant environmental and health threat globally. Traditional remediation methods like solidification/stabilization have limitations, prompting the need for alternative techniques. Soil washing emerges as a promising approach, employing physical and chemical methods to effectively remove contaminants. This paper explores soil washing methods, focusing on sites contaminated with heavy metals such as zinc, lead, nickel, mercury, arsenic, copper, chromium, and cadmium, particularly influenced by military and industrial activities. Several techniques, including physical separation and chemical extraction, are discussed, which consider a few factors such as magnetism, density, size, and hydrophobicity to concentrate metal contaminants and solubilize soils. Physical separation targets particulate contaminants, while chemical extraction addresses non-detrital metals or soils with adsorbed ionic forms. The study also analyses field applications of soil washing systems and the implementation of remediation techniques. It emphasizes the need for innovative soil remediation strategies to mitigate the adverse effects of heavy metal contamination on soil quality and human health.[...] Read more. Full text

by Hui Yee Ngieng, Muhammad Noor Hazwan Jusoh, Noraziah Ahmad, Md Abdullah Al Masud, Hasara Samaraweera, Mohamed Mostafa Mohamed

Ind. Domest. Waste Manag. 2024, 4(1), pp 42-55; https://doi.org/10.53623/idwm.v4i1.442

49 views
Abstract Soil pollution is one of the concern issues in the Asia region. Soil acts as a shelter for underground microorganisms and provides nutrients for plants. Most of the organic contaminants are sourced from agriculture and industrial areas. Organic contaminants which are volatilized and immiscible lead to air and water pollution. Electrokinetic remediation is a technology that has been developed for soil remediation since a few decades ago. It is not fully developed and is still under investigation. Electrokinetic remediation is being applied to improve the removal efficiency of organic contaminants which exist in low hydraulic conductivity of soil or fine-grained soil.  Generally, a low direct current, 1DCV/cm is applied. Facilitating agents including surfactant and co-solvent combined with electrokinetic remediation eliminated more organic contaminants compared with electrokinetic remediation alone. Electrokinetic remediation with the addition of bioremediation or phytoremediation process manipulates the transportation of organic contaminants in soil to increase the efficiency of remediation technologies. Electrokinetic remediation is recommended due to its flexibility, cost-effectiveness, and safety. One of the drawbacks is low effectiveness in removing non-polar organic pollutants due to weak desorption capacity and poor solubility in water. Co-solvents and surfactants can be introduced as alternatives to enhancing the solubility of non-polar pollutants and reducing surface tension, which improves their mobility within the soil matrix. These facilitating agents help improve the overall effectiveness of electrokinetic remediation, particularly for challenging contaminants.[...] Read more. Full text