Environmental Monitoring at and around the Matuail Landfill Site of Dhaka City using Remote Sensing

Rapid urban population growth and flourishing incomes have increased waste production in Dhaka city. A part of daily produced Municipal Solid Waste (MSW) is disposed of at Matuail sanitary landfill located within Jatrabari Thana, Dhaka. This study has analyzed the environmental impacts at and around this landfill using remote sensing techniques. The objective of this research is to develop a means of environmental monitoring at the landfill site and its surroundings through the implementation of various time-series remote sensing indices e.g., Land Surface Temperature (LST), Normalized Difference Vegetation Index (NDVI), Soil Adjusted Vegetation Index (SAVI), and Modified Soil Adjusted Vegetation Index (MSAVI). LST is used to observe the Spatio-temporal pattern of temperature distribution. NDVI, SAVI, and MSAVI are the Bio-indicators and they are helpful to analyze the vegetation health condition at and around the landfill area. From the result of LST, it is observed that the average temperature of the Jatrabarithana has increased from 23.12℃ in 1993 to an optimum temperature of 35.20℃ in 2013, then it went down to 29.09℃ in 2018. The NDVI result for the study period shows that the percentages of ‘Bare Soil’ and ‘Structural Object’ have increased drastically from 10% to 41.20% and 13.30% to 31.52% respectively for these 25 years in Jatrabarithana. On the other hand, the percentages of ‘Shrub and Grassland’ and ‘Moderate Vegetation’ have decreased from 54.20% to 25.15% and 12.55% to 0% respectively. SAVI and MSAVI also show evidence of increasing the amount of bare soil and structural object and decreasing the amount of vegetation. Due to the waste stabilization process, and inappropriate management system at the Matuail landfill, along with urbanization, industrial activity, and deforestation, a harmful effect has been done to the surrounding environment. As an outcome, the temperature has risen rapidly and the amount of vegetation has declined to a significant extent. Journal of Engineering Science 12(3), 2021, 127-138

Open landfill site and threat to the proximity resident’s: Addressing perceived consequences of unscientific solid waste dumping using GIS techniques

Municipal solid waste (MSW) disposal is a rapidly expanding sector that caters to the rising demand for disposal facilities; as a result, MSW treatment is becoming a significant challenge in concern to environmental and public health. The by-products of solid waste dumped in landfills have negative consequences on the environment and people living near disposal sites. This research aimed to assess whether the disposal of garbage in landfills affected the people who live near them. Consequently, residents living near MSW disposal facilities are exposed to various risks. A systematic questionnaire was devised and disseminated in this research to examine the adjacent people's concerns and attitudes around the landfill of the rapidly expanding Siliguri city of West Bengal. It was accomplished by assessing the opinions of persons living within the 1000m of the landfill site and how it impacts their life. The novelty of the research includes geographical analysis of physical impressions, including odour nuisance, breathing problems, impacts of flies and mosquitoes, water contamination, issues due to illegal burning, and health-related problems, which was conducted using geographic information system methodologies. Besides, the Landfill satisfaction index (LSI) tool was used to assess the perception of the people residing near the landfill. Also, to statistically validate the perception of the people related to the impact of landfills on their life, gamma coefficient (y) test of Goodman-Kruskal was applied. The findings reveal that the majority of the respondent within 600m are more susceptible to various risks due to unscientific landfill. Subsequently, a large portion of the responding sample was aware of the detrimental effects of landfills on the health and environment, therefore, individuals living near the dump yard preferred to live farther away. The findings also reveal that geographical proximity has a clear relationship between respondent perception and distance to the landfill. The study concludes with a discussion on how the research results may be beneficial for designing landfill sites and can be utilized by urban planners, environmentalists, and engineers.

Awareness and health risk protection behaviours of scavengers in the Gbalahi landfill site, Ghana, in the era of sustainable development

Waste picking is a pivotal in achieving sustainable waste management, environment health and economic development in the era of sustainable development. The study assessed the practices, knowledge, perception and health risk protection behaviours of waste scavengers in the Gbalahi landfill site. A total of 60 scavengers were conveniently sampled and interviewed. The study revealed that 93% of the waste scavengers sort waste using hooks and their bare hands. The study also showed 62% of the respondents have ever been physically abused by other scavengers. A good number of scavengers believed they have been fortified against “dirt diseases” during their childhood and have developed natural immunity against diseases. The knowledge of scavengers was skewed towards economic benefits as they viewed waste picking as a survival strategy. Discrimination and physical abuse posed a seemingly significant psychological health risk to majority of them. Safety and protection practices are limited to the use of pieces of clothes to cover the nose, wearing of multiple clothes and worn-out boots recovered from the landfill. Most of the respondents risk being exposed to the virus and pathogens. It is recommended that education and increased sensitisation should be encouraged and implemented by the Environmental Protection Agency (EPA), Ghana Health Service and other allied institutions in order to regularise and ensure the health and safety of waste scavengers.

Numerical simulation of uneven settlement of municipal solid waste landfill by FLAC 3D

After the landfill site is sealed, the uneven settlement is related to the safety of reutilisation of the site, and it is critical to calculate the uneven settlement of the site without error. In this article, the soil parameter of garbage body was changed with biodegradation. Fast Lagrangian Analysis of Continua in three dimensions (FLAC 3D) numerical simulation was applied to the settlement of the landfill site closure. In calculating the settlement of landfill, the soil parameters of landfill with age were obtained by field drilling experiments. The parameters can reflect the characteristics of soil organic matter in different biodegradation stages. Finally, the uneven settlement within 20 years of the closure period was obtained by the numerical simulation taking Jinzhou Nanshan landfill as an example. The results show that the settlement with the age increases gradually, but the rate will be more and more moderate, and the maximum subsidence value in the sealing field after 20 years will be 9.11 m, 15.71% of the maximum elevation. Around the landfill slope position of uneven settlement rate is bigger, and the maximum angle of uneven settlement is up to 45°. But the middle position is small, which is close to 0°.