Municipal Solid Waste Dumpsite Research Articles

An investigation on mobility of heavy metals for assessing the reusability of soil-like material reclaimed from mining of municipal solid waste dumpsites

Landfill mining, often referred to as “bio-mining”, enables the recovery of resources, including combustible, compostable, and recyclable fractions from landfills. However, most of the materials mined from old landfills mainly consist of soil-like materials (SLM). The reuse of SLM depends on the concentration of contaminants, such as heavy metals, soluble salts, etc. A sound risk assessment requires sequential extraction to determine the bioavailability of heavy metals. This study focuses on the mobility and chemical speciation of heavy metals in SLM from four old municipal solid waste dumpsites in India by performing selective sequential extraction. Additionally, the study compares the results with those of four previous investigations to identify international similarities. It has been observed that Zn was mainly available in the reducible phase (average 41%), whereas Ni and Cr proved to have the highest distribution in the residual phase (64% and 71%, respectively). Pb analysis showed a large portion in the oxidizable phase (39%), while Cu was mainly present in the oxidizable (37%) and residual (39%) phases. Similarities with previous investigations were observed for Zn (primarily reducible 48%), Ni (residual 52%), and Cu (oxidizable 56%). Correlation analysis showed that Ni correlated with all heavy metals (ρ = 0.71–0.78), except with Cu. The present study suggested that Zn and Pb are associated with a high risk of pollution due to their maximum distribution in the bioavailable phase. The findings of the study can be used to assess the heavy metal contamination potential of SLM prior to its reuse in offsite applications.

Mathematical modeling and numerical simulation technique for selected heavy metal transport in MSW dumpsite

The study focused on development of mathematical modeling and numerical simulation technique for selected heavy metal transport in Uyo municipal solid waste dumpsite in Akwa Ibom State to investigate the level in depth to which leachate from the dumpsite extends and the quantity of leachate at various depth of the dumpsite soil. Uyo waste dumpsite is operating open dumping system where provisions are not made for preservation and conservation of soil and water quality, hence, the need for this study. Three monitoring pits within Uyo waste dumpsite were constructed and infiltration runs were measured, and soil samples were collected beside infiltration points from nine designated depths ranging from 0 to 0.9 m for modeling heavy metal transport in the soil. Data collected were subjected to descriptive and inferential statistics while the COMSOL Multiphysics software 6.0 was used to simulate the movement of pollutants in the soil. It was observed that heavy metal contaminant transport in soil of the study area is in the power functional form. The transport of heavy metals in the dumpsite can be described by a power model from linear regression and a numerical model based on finite element. Their validation equations showed that the predicted and the observed concentrations yielded a very high R2 value of over 95%. The power model and the COMSOL finite element model show very strong correlation for all selected heavy metals. Findings from the study has identified level in depth to which leachate from the dumpsite extends and the quantity of leachate at various depth of the dumpsite soil which can be accurately predicted using leachate transport model of this study.

Surface emission determination of selected trace gases from an active municipal solid waste dumpsite under the surface physicochemical heterogeneity.

Karadiyana municipal solid waste (MSW) dumpsite in Colombo, Sri Lanka, has been in operation for over 30years and was evaluated for its surface Volatile Organic Compounds (VOCs), Ammonia (NH3), and Hydrogen sulfide (H2S) emissions. Based on the surface conditions and waste characters, the dump surface was divided into eight cells, and multiple samplings were done using static flux chamber methods. The study observed that the average flux rates of VOCs, H2S, and NH3 were 137.2±243.8, 6.63±15.9, and 14.2±16.2mgm-2h-1 throughout the dump site. The highest average VOCs and H2S flux rates (828.6, 24.3mgm-2h-1) were reported from new organic waste with a considerable fraction (62.5, 35.6%) from the total emission (61.0, 3.1 Kg d-1). Leachate-flowing trenches produced the highest NH3 flux rate (36.0mgm-2h-1), while the highest emission fraction (47.5%) from the total (12.0 Kg d-1) was reported on old mixed waste with vegetation. The moisture content of the organic waste layers is positively correlated with these trace gas flux rates, and the NH3 flux rates depend on the pH of the surface. Results showed that the age of the waste determines the trace gas emission rate, and leachate provides an ideal pathway for landfill trace gas migration to the atmosphere. Gas collection and purification systems are essential for the initial waste dumping area and leachate treatment system. The arrangement of a proper drainage system on the dump would reduce trace gas emissions.

Effect of expansive soils on swelling behavior of encapsulated sodium bentonite of geosynthetic clay liner (GCL)

Due to the rapid urbanization of Indian cities, the generation of MSW is exponentially increasing. The confinement of the hazardous emission from a municipal solid waste (MSW) dumpsite is the major responsibility of management and engineers. Landfill gases and leachate generation are the results of chemical and biological activities in municipal solid waste and its decomposition process. The seepage control of leachate is a crucial aspect of MSW management. The flow of leachate to groundwater is one of the major causes of groundwater contamination resulting in human health risks nearby population. Geosynthetic clay liners (GCLs) are the most preferred options to restrict the flow of leachate from dumpsite to groundwater. GCL consists of sodium/ calcium bentonite as an encapsulated material between woven and non-woven carriers. The swelling behavior of sodium bentonite with low hydraulic conductivity makes it suitable to prevent the flow through it. In this study, the swelling nature of sodium bentonite was assessed in combination with expansive soils. The soils were collected from two different regions of Uttar Pradesh as Banda and Mahoba districts. The results showed that the swelling tendency of sodium bentonite can be enhanced by using specific proportions of expansive soils.

Isolation and screening of low-density polyethylene (LDPE) bags degrading bacteria from Addis Ababa municipal solid waste disposal site “Koshe”

PurposeThis study aims to screen bacterial isolates from the Addis Ababa municipal solid waste dumping site (Koshe) for the biodegradation of low-density polyethylene bags and analyzes their efficiency in degrading plastic bags.MethodsIn this study, low-density polyethylene bag-degrading bacteria were isolated from the Koshe municipal solid waste disposal area in Addis Ababa, Ethiopia. Screening of isolates for low-density polyethylene bag biodegradation was carried out using a clear zone method. Additionally, the efficiency of the isolates for low-density polyethylene biodegradation was evaluated using the weight loss method, scanning electron microscopy analysis, and Fourier transform infrared analysis. Finally, molecular identification of potential low-density polyethylene degrader bacterial isolates was done by 16S rDNA sequencing.ResultsIsolates KS35, KS14, and KS119 resulted in significant weight loss of low-density polyethylene film (42.87 ± 1.91%, 37.2 ± 3.06%, and 23.87 ± 0.11% weight loss, respectively). These isolates were selected for further biodegradation study using scanning electron microscopy and Fourier transform infrared analysis. Scanning electron microscopy analysis shows the formation of pores, pits, and distortion of the plastic surface. Fourier transform infrared analysis indicates the appearance of new peaks at the surface of low-density polyethylene films. Phylogenetic analysis of the three potential bacterial isolates was also carried out, and the result indicates that the sequence of isolate KS35 had 99% similarity with sequences of Methylobacterium radiotolerans MN525302. Isolate KS119 had 100% similarity with Methylobacterium fujisawaense KT720189, and the sequence of isolate KS14 had 99% similarity with species of Lysinibacillus fusiformis.ConclusionsWeight loss, scanning electron microscopy analysis, and Fourier transform infrared analysis results show that isolates KS35, KS14, and KS119 have high potential in degrading low-density polyethylene bags.

Decoding the PLFA profiling of microbial community structure in soils contaminated with municipal solid wastes

This study aimed to assess the influence of municipal solid waste (MSW) disposal on soil microbial communities. Soil samples from 20 different locations of an MSW dumping site contaminated with toxic heavy metals (HMs) and a native forest (as control) were collected for phospholipid fatty acid (PLFA) profiling to predict microbial community responses towards unsegregated disposal of MSW. PLFA biomarkers specific to arbuscular mycorrhizal fungi (AMF), Gram-negative and Gram-positive bacteria, fungi, eukaryotes, actinomycetes, anaerobes, and microbial stress markers-fungi: bacteria (F/B) ratio, Gram-positive/Gram-negative (GP/GN) ratio, Gram-negative stress (GNStr) ratio and predator/prey ratio along with AMF spore density and the total HM content (Cu, Cr, Cd, Mn, Zn, and Ni) were assessed.The results showed that all of the PLFA microbial biomarkers and the F/B ratio were positively correlated, while HMs and microbial stress markers were negatively correlated. The significant correlation of AMF biomass with all microbial groups, the F/B ratio, and T. PLFA confirmed its significance as a key predictor of microbial biomass. With AMF and T. PLFA, Cd and Cr had a weak or negative connection. Among the toxic HMs, Zn and Cd had the greatest impact on microbial populations. Vegetation did not have any significant effect on soil microbial communities. This research will aid in the development of bioinoculants for the bioremediation of MSW-polluted sites and will improve our understanding of the soil microbial community's ability to resist, recover, and adapt to toxic waste contamination.

Analysis of the Uptake and Distribution of Heavy Metals in Sweet Corn Grown on Municipal Solid Waste Dumpsite Soil in Delta State, Nigeria

Analysis of the Uptake and Distribution of Heavy Metals in Sweet Corn Grown on Municipal Solid Waste Dumpsite Soil in Delta State, Nigeria

Leachate Characterization Generated from Municipal Solid waste at Landfill Site Ghazipur, New Delhi

Abstract: The management of municipal solid waste (MSW) is one of the key environmental issues facing Indian cities, mostly as a result of the country's growing industrialisation and urbanisation. According to numerous studies, open dumps and landfills are used to dispose of around 90% of solid waste in an improper manner. Pollutants can escape a poorly constructed landfill in a number of ways. Leachate can escape from a landfill or dumpsite and contaminate groundwater and surface water if the soil above or below it is porous. Therefore, In this paper an attempt is made to characterize the leachate produced by municipal solid waste dumping site of Ghazipur, New Delhi which is located at Latitude: 28° 37' 30.8784". Longitude: 77° 19' 40.764" near the Delhi-UP border. In this investigation, about 12 leachate parameters were identified. Three sample sites at the bottom of the landfill, spaced 7 metres apart, were used to characterise the leachate samples. All of the leachate samples had an acidic pH value ranging from 6.24 to 6.88, it is discovered. All of the sample’s conductivity and total dissolved solids ranged from 567 to 1945 S/cm and 513 to 1289 ppm respectively. Similar dissolved ions such chloride, calcium, sodium, nitrate, and potassium were found in the leachate sample. The majority of the ions were discovered to be above the standards-permitted level. The present study concludes that characterization of landfill leachate is important to identify the most critical pollutants present in the leachate and thereby to introduce suitable and applicable technologies such as in-situ impermeable barriers etc.

Isolation and identification of promising antibiotic-producing bacteria

Abstract Multiple stresses in waste dumpsite soils can drive antibiotic production as one of the strategies for survival. Bacteria are the most prolific producers of antibiotics. This study investigated the antibiotic production potential of bacteria isolated from Bahir Dar city municipal solid waste dumpsite (MSWDS). Bacteria were isolated from soil collected from the dumpsite on starch casein or nutrient agar. The isolates were carefully screened for antimicrobial activity against six pathogenic bacterial test strains. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were also determined from cell-free metabolites of the most promising isolates. Isolates showing antimicrobial activity were identified using cultural and biochemical methods. A total of 143 distinctive colonies were obtained and tentatively identified to 13 bacterial genera. Twenty-six (18.18%) of the isolates (six Bacillus and 20 actinobacteria related) demonstrated antimicrobial activities at least against one of the tested bacterial strains. These isolates were related to two actinobacterial and 11 other bacterial genera. Seven out of 26 isolates showed a broad-spectrum of antibiotic activities. Two isolates, which showed a wide spectrum, were selected for the MIC and MBC tests against Escherichia coli and Staphylococcus aureus. The MIC and MBC of the isolates were recorded to be 250–500 µg/mL against the test strains. Bahir Dar city MSWDS contained a high incidence of antibiotic-producing bacteria. Strain level identification of the isolates and detailed characterization of the metabolites will give a good insight into the antimicrobial production potential in the waste dumpsite.

Determination of risk of spontaneous waste ignition and leachate quality for open municipal solid waste dumpsite

The waste receiving capacity of most municipal solid waste (MSW) landfill sites in India is exhausted, resulting in the formation of larger waste heaps. In the majority of Indian cities, these old waste heaps are prone to frequent smoldering and ignition resulting into fires. In this study, the potential risk of spontaneous ignition of landfilled waste at landfill surface was analyzed based on the physico-chemical characteristics of waste, carbon monoxide (CO) levels, landfill surface temperature (LST). The leachate pollution index was also determined to analyze the leachate quality for three different seasons (monsoon, pre-monsoon and post-monsoon). The regression analysis was carried out to understand the thermal properties (smoldering temperature, smoldering time, ignition temperature etc.) of MSW. The results showed that old waste has a higher tendency to undergo ignition compared to fresh waste. It has also been observed that the lower MC of old waste samples in the range of 3.4% and 18.2% is the most likely cause of early smoldering (106.6–109.5 °C) and ignition (198.6–208.4 °C) of old waste. In pre-monsoon season, CO concentrations for sub-surface (10–30 cm depth) smoldering events (SSE) were observed to be between ∼ 150 to 200 ppm. This CO level substantially dropped to 10 ± 1 ppm in the post-monsoon season. The estimation of the leachate pollution index (LPI) showed an index score of 27.35, 30.47 and 10.71 for pre-monsoon, monsoon and post-monsoon seasons, respectively. The determination of CO levels, increased LST and physico-chemical properties of landfilled waste will greatly assist in the abatement of environmental pollution arising from landfill fires.

Geospatial alternatives for quantification of bio-thermal influence zone in the vicinity of a solid waste dump.

Owing to the release of toxic gases, leachate and thermal emissions that originate from waste dumps, these sites significantly impact environmental sustainability. The study attempts to assess the deleterious impact of municipal solid waste (MSW) dump on surrounding forested landscape by employing geospatial technologies, which are cost and time-effective. For this purpose, temporal period ranging from 2015 to 2020, having 41 valid satellite observations has been selected for study. Firstly, the radii of intense hazardous zone and hazardous zone have been measured, as two separate parameters, which are 580 ± 30 m and 1260 ± 30 m, respectively. Secondly, average spatial extent of bio-influence zone is measured to be 1262 m while the average thermal influence zone extends up to 530 m around the MSW dumping site. A detailed analysis of influence zone variations reveals that the bio-influence zone depends on multitude of meteorological parameters, whereas the thermal influence zone relies mainly on seasonal temperature fluctuations. Moreover, the level of severity of emissions from MSW decomposition directly depends upon temperature. The long-term variability analysis of these hazardous zones reveals the stationarity of their spatial extents, signifying forest resilience. This study has proved significance of geospatial techniques as an alternate of expensive and time intensive assessment methods involving in situ measurements. So the proposed technique is beneficial for environmentalists, decision-makers and municipal authorities for analysing the extent and severity of MSW pollutants for forest community to address the problem of ecological degradation.

A pilot-scale study of the integrated phycoremediation-photolytic ozonation based municipal solid waste leachate treatment process

Municipal solid waste (MSW) leachate is a highly polluted liquid that accumulates in the landfill and contains a high concentration of toxic pollutants which can pollute the surrounding surface water and groundwater as well, if not treated properly. In this study, an integrated approach of phycoremediation with photolytic ozonation was employed for the leachate collected from the MSW dumpsite which has high Chemical Oxygen Demand (COD) and ammonium (NH4+) levels. Photolytic ozonation treatment was employed as a pre-treatment step under operating parameters of pH: 9.0; Ozone dosage: 5 g/h; UV-C: λ = 254 nm; and contact time: 60 min, in which the COD and NH4+ in the leachate was reduced up to 81% and 95%, respectively. The selected algae Chlorella vulgaris (C.vulgaris) was employed in a lab-scale study to optimize the inoculum conditions in the photolytic ozonated leachate (POL). The specific growth rate of C.vulgaris was observed as 0.14/d in the POL at the optimized condition (inoculum size of 25% (T25)) during the study period of 11 days. High-rate algal pond (HRAP) was employed for the pilot-scale study in controlled environmental conditions as in the T25 experimental run for the assessment of POL treatment and biomass production. C.vulgaris reduced the concentration of pollutants COD, NH4+, and heavy metals (Cu, Fe) in the POL up to 93%, 94%, and 71%, respectively, with the dry biomass productivity of 0.727 g/L/d which is 3 times higher than the biomass productivity of C.vulgaris in freshwater conditions. The biochemical composition (carbohydrates, proteins, and lipids) of the harvested biomass has higher lipid production with lipid productivity of 120 mg/L/d which can be used as a feedstock for the production of value-a dded products.

Identifying Municipal Solid Waste Dumping Site Location Using AHP and GIS Techniques: A Case Study of Coimbatore District, India

Identifying Municipal Solid Waste Dumping Site Location Using AHP and GIS Techniques: A Case Study of Coimbatore District, India

Heavy metal pollution in leachates and its impacts on the quality of groundwater resources around Iringa municipal solid waste dumpsite.

Heavy metal pollution in groundwater due to leachates leaking from the Iringa municipal dumpsite was investigated. The pollution was studied by analyzing pH, electrical conductivity (EC), total dissolved solids (TDS), and heavy metals (Fe, Pb, Cr, Cd, Cu, Ni, Mn, and Zn) in leachates collected within the dumpsite and groundwater samples from residential wells close to the dumpsite. The pH of the leachate samples varied from 7.40 to 9.10, implying alkaline behavior and the methanogenic phase of solid waste deposits. The levels of EC, TDS, and heavy metals (Fe, Pb, Cr, Cu, Ni, Mn, and Zn) in leachates were above the national and/or international standards. On other hand, groundwater samples presented pH values ranging from 7.15 to 7.60 which were within the World Health Organization acceptable limit. The concentrations of EC, TDS, Fe, Pb, Ni, Mn, and Zn in most groundwater samples exceeded the national and/or international permissible limits for drinking water. In addition, the water quality indices (WQI) of groundwater samples ranged between 8.30 and 17.90, which implied the excellent quality of groundwater sources. However, the presence of high levels of heavy metals above the permissible limits in both leachate and groundwater samples signified potential risks to the environment and public health. Therefore, the present study calls for proper management of municipal solid waste to reduce the potential risks of further contamination on the groundwater resources and environment around the Iringa municipal dumpsite.

Study of surface water quality for domestic use near a municipal solid waste dumping site in Bhuasuni, Odisha, India

Study of surface water quality for domestic use near a municipal solid waste dumping site in Bhuasuni, Odisha, India

Assessing the risk of landfill leachate on the groundwater quality of Chandigarh

Aim: Unscientific dumping of municipal solid waste (MSW) is still prevalent in the developing world, leading to adverse environmental and human health consequences. This study was conducted to assess the groundwater contamination due to leachate from the MSW dumping site in Chandigarh. Methodology: Leachate and groundwater samples from different sources were collected for two sampling periods from the vicinity of dumping site within a radius of 3 km. Collected samples were analyzed for physico-chemical parameters, heavy metals and microbiological examination. Results: The result showed high load of organic and inorganic contaminants in leachate as it had a higher COD value (10008 mgl-1 and 18280 mg l-1) whereas ammoniacal nitrogen (NH4+-N) levels were 2389 mg l-1 and 5796 mg l-1 for two sampling periods. The concentration of Cu and Zn were highest amongst all the analyzed heavy metals in leachate samples. Almost all parameters in groundwater samples exceeded the BIS and WHO standard limits, which showed high contamination of groundwater surrounding the dumping site. Interpretation: Higher concentrations of COD and NH4+-N in most groundwater samples indicates percolation of landfill leachate into the groundwater aquifer, leading to its contamination. Groundwater samples collected near the dumping sites of lower depth have higher levels of pollutants than the samples collected from higher depth.0

Analytical hierarchy process tool in Google Earth Engine platform: a case study of a tropical landfill site suitability.

Kolkata being a metropolitan city in India has its main municipal solid waste dumpsite situated at Dhapa just adjacent to the East Kolkata Wetlands (Ramsar site). The current prevalent situation at Dhapa is open dumping leading to various contaminations and hazards putting forth the need to look for alternative sites where the landfiilling operation can be shifted to using scientific methods. A user interface (UI)-based analytical hierarchy process (AHP) tool has been developed within the Google Earth Engine (GEE) cloud platform to find out the alternative dumping sites using geospatial layers. AHP function is not available as a native algorithm or developed by any researcher in GEE. The tool has three major functionalities, of which the first one handles the UI elements. The AHP procedure is within another function, and the last function integrates the AHP coefficients to the layers generating the final suitability layer. Users can also upload comparison matrix as GEE asset in the form ofCSV file which gets automatically integrated into the AHP to calculate the coefficients and consistency ratio to generate the spatial suitability layers. This approach showcases a generalized AHP function within the GEE environment, which has been done for the first time. The tool is designed in the cloud platform which is dynamic, robust and suitable for use in various AHP-based suitability analysis in environmental monitoring and assessment.

Factors Affecting the Intensity of Color Released In Water Extract by Soil-Like Material Obtained From Mining of Old MSW Dumps

This paper presents the analysis of release of dark-colored leachate from soil-like material (SLM) mined from three old municipal solid waste dump sites of before its reuse as earth-fill. If SLM is to be re-used in earth-fill, the release of dark-colored leachate can cause coloration of the surrounding water bodies. Laboratory studies (in terms of single batch leaching) were undertaken to quantify the release of color and identify the source/cause of the phenomenon. Influence of repeated washing, heating at various temperature, and aeration of SLM on the intensity of release of color was identified. Correlation of color with total dissolved solids and volatile dissolved solids was also established. The intensity of color of water extract from SLM in platinum cobalt unit (PCU) was found to in the range of 288-712, 465-485 and 740-925 from Delhi, Kadapa and Hyderabad dumpsites respectively. In contrast, the intensity of color in water released from local soils was found to be 25-30 PCU. Organic content present in SLM was identified as the primary cause for the release of color. Results showed that large quantity of water (70-120 ml per gram of SLM) was required to cause significant reduction in the intensity of color. Heating of SLM to 500°C was observed to reduce the color very effectively but short-term aeration of SLM did not reduce color. Good correlation of volatile dissolved solids with color was observed which further confirmed the organic content as the main reason for the release of dark-colored leachate from SLM.

Physicochemistry and microbial diversity of a municipal solid waste dumpsite leachate revealed by metagenomics

Physicochemistry and microbial diversity of a municipal solid waste dumpsite leachate revealed by metagenomics

Quantification of landfill gas emissions and energy production potential in Tirupati Municipal solid waste disposal site by LandGEM mathematical model

The present key challenges the world is currently facing are the environmental pollution, climate change and energy crisis. The anthropogenic emissions of carbon dioxide due to burning of fossil fuels for energy production and other greenhouse gas emissions are considered unsustainable, and whole world is having a paradigm shift towards the renewable energy. The one of the major contributor of the greenhouse gases like methane, carbon dioxide are the municipal solid waste landfill sites. The landfill sites contains nearly 50–60% of organic contents, and they undergo anaerobic decomposition with a help microbes in the waste dumps contribute to the higher percent of methane emissions. There is now enhanced public awareness on sustainable products, and commodities usage in their daily needs, hence the global warming can be slowed down and devise an environmentally sound sustainable society. The present study aimed to provide a methodology to quantify the amount of methane and carbon-di-oxide emitted from the Tirupati municipal solid waste dumpsite using LandGEM3.02 model and empirical equation to estimate the renewable energy potential. The method provided was simple and more accurate having higher efficiency in predicting the landfill emissions and subsequently the energy potential. The study shows that the energy emission potential are maximum to the waste with a higher fraction of biodegradable organic content. Therefore, the method can be implemented in all the landfills by the policy makers to predict the methane emissions and control the greenhouse gas emissions by sequestering the methane and carbon dioxide optimally for energy production.•Landfill gases are a primary constituent in greenhouse gases and has potential for energy production.•The results from this study showed an abundant quantity of methane and carbon dioxide are emitted from tripathi landfill site.•The study concludes that methane can be extracted and used as alternative source of sustainable energy.