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Open-pit coal mining inevitably damages the soil and vegetation in mining areas. Currently, the restoration of cold and arid open-pit mines in Xinjiang, China, is still in the initial exploratory stage, especially the changes in soil nutrients in spoil dumps over time. Dynamic remote sensing monitoring of vegetation in mining areas and their correlation are relatively rare. Using the Heishan Open Pit in Xinjiang, China, as a case, soil samples were collected during different discharge periods to analyze the changes in soil nutrients and uncover the restoration mechanisms. Based on four Landsat images from 2018 to 2023, the remote sensing ecological index (RSEI) and fractional vegetation cover (FVC) were obtained to evaluate the effect of mine restoration. Additionally, the correlation between vegetation changes and soil nutrients was analyzed. The results indicated that (i) the contents of nitrogen (N), phosphorus (P), potassium (K), and organic matter (OM) in the soil increased with the duration of the restoration period. (ii) When the restoration time of the dump exceeds 5 years, N, P, K, and OM content is higher than that of the original surface-covered vegetation area. (iii) Notably, under the same restoration aging, the soil in the artificial mine restoration demonstration base had significantly higher contents of these nutrients compared to the soil naturally restored in the dump. (iv) Over the past five years, the RSEI and FVC in the Heishan Open Pit showed an overall upward trend. The slope remediation and mine restoration project significantly increased the RSEI and FVC values in the mining area. (v) Air humidity and surface temperature were identified as key natural factors affecting the RSEI and FVC in cold and arid open pit. The correlation coefficients between soil nutrient content and vegetation coverage were higher than 0.78, indicating a close and complementary relationship between the two. The above results can clarify the time–effect relationship between natural recovery and artificial restoration of spoil dumps in cold and arid mining areas in Xinjiang, further promoting the research and practice of mine restoration technology in cold and arid open pits. [ABSTRACT FROM AUTHOR]

Forest recreation can be successfully used for psychological relaxation and can serve as a remedy for common stress-related problems. The special form of forest recreation intended for restoration is forest bathing. These activities might be disrupted by some factors, such as viewing buildings in the forest or using a computer in nature, which interrupt psychological relaxation. One factor that might interrupt psychological relaxation is the occurrence of an open dump in the forest during an outdoor experience. To test the hypothesis that an open dump might decrease psychological relaxation, a case study using a randomized, controlled crossover design was conducted. For this purpose, two groups of healthy young adults viewed a control forest or a forest with an open dump in reverse order and filled in psychological questionnaires after each stimulus. Participants wore oblique eye patches to stop their visual stimulation before the experimental stimulation, and the physical environment was monitored. The results were analyzed using the two-way repeated measures ANOVA. The measured negative psychological indicators significantly increased after viewing the forest with waste, and the five indicators of the Profile of Mood States increased: tension–anxiety, depression–dejection, anger–hostility, fatigue, and confusion. In addition, the negative aspect of the Positive and Negative Affect Schedule increased in comparison to the control and pretest. The measured positive indicators significantly decreased after viewing the forest with waste, the positive aspect of the Positive and Negative Affect Schedule decreased, and the Restorative Outcome Scale and Subjective Vitality scores decreased (in comparison to the control and pretest). The occurrence of an open dump in the forest might interrupt a normal restorative experience in the forest by reducing psychological relaxation. Nevertheless, the mechanism of these relevancies is not known, and thus, it will be further investigated. In addition, in a future study, the size of the impact of these open dumps on normal everyday experiences should be investigated. It is proposed that different mechanisms might be responsible for these reactions; however, the aim of this study is to only measure this reaction. The identified psychological reasons for these mechanisms can be assessed in further studies. [ABSTRACT FROM AUTHOR]

Open-pit coal mining inevitably damages the soil and vegetation in mining areas. Currently, the restoration of cold and arid open-pit mines in Xinjiang, China, is still in the initial exploratory stage, especially the changes in soil nutrients in spoil dumps over time. Dynamic remote sensing monitoring of vegetation in mining areas and their correlation are relatively rare. Using the Heishan Open Pit in Xinjiang, China, as a case, soil samples were collected during different discharge periods to analyze the changes in soil nutrients and uncover the restoration mechanisms. Based on four Landsat images from 2018 to 2023, the remote sensing ecological index (RSEI) and fractional vegetation cover (FVC) were obtained to evaluate the effect of mine restoration. Additionally, the correlation between vegetation changes and soil nutrients was analyzed. The results indicated that (i) the contents of nitrogen (N), phosphorus (P), potassium (K), and organic matter (OM) in the soil increased with the duration of the restoration period. (ii) When the restoration time of the dump exceeds 5 years, N, P, K, and OM content is higher than that of the original surface-covered vegetation area. (iii) Notably, under the same restoration aging, the soil in the artificial mine restoration demonstration base had significantly higher contents of these nutrients compared to the soil naturally restored in the dump. (iv) Over the past five years, the RSEI and FVC in the Heishan Open Pit showed an overall upward trend. The slope remediation and mine restoration project significantly increased the RSEI and FVC values in the mining area. (v) Air humidity and surface temperature were identified as key natural factors affecting the RSEI and FVC in cold and arid open pit. The correlation coefficients between soil nutrient content and vegetation coverage were higher than 0.78, indicating a close and complementary relationship between the two. The above results can clarify the time–effect relationship between natural recovery and artificial restoration of spoil dumps in cold and arid mining areas in Xinjiang, further promoting the research and practice of mine restoration technology in cold and arid open pits.

Generation of municipal solid waste (MSW) depends upon lifestyle, urbanization and income level of population. Solid waste management is one of the essential parameters for the sustainable development of any city. Kanpur is one of the Indian cities with a population greater than 4 million having critical environmental and socio-economic issues of municipal solid waste management. Earlier some of the researchers highlighted the prevailing flaws and loopholes of the system, leading to poor controlled practices in the city till 2008. They also urged some remediates to the policymakers to fortify the system. In the present scenario, a daily waste generation amounts to be 1500 metric tonnes per day. This solid waste collection and transportation to the dumping site costs nearly 0.21 billion Rupees in a year. In the present paper, an attempt has been made to review the quality, physical and chemical composition, and policy of government authorities to manage the MSW year-wise year. The effect of open dumping of MSW on and nearby ground and surface water bodies in the study area is also highlighted. A comparative study between open dumping and engineered landfills is also made mainly with a focus on their suitability. The average net calorific value of the municipal solid is estimated as 2288 kcal/Kg which is significant to convert Waste to Energy (WtE). This work concludes with the possibilities of changing greenhouse gases to landfill gasses and their collection mechanism, electrical energy generation as per the composition and type of waste collected at the waste management plant. The suggestive measures equipped in this paper may lend a hand to the decision-makers/ municipal authorities to get an effective and environment-friendly MSW management system. [ABSTRACT FROM AUTHOR]

The final disposal of solid waste in dumpsites can result in the migration of leachate components through the soil, contaminating it as well as the groundwater. The purpose of this manuscript was to analyze the contamination of a dumpsite along with three unlined leachate ponds that operated for approximately 25 years. Soil, surface water from three leachate lagoons, and groundwater samples were collected. Chemical analyses such as chloride, ammonia nitrogen, and total organic carbon were performed. The present work also aimed at elaborating the local flow pattern map and the assessment of subsoil. The results showed local subsoil mostly clayey, also occurring a region of sandy predominance, and great variation of rocky outcrops depth. The groundwater flow occurs from the waste towards one of the leachate lagoons. The leachate lagoon located closer to deposited area presented the highest concentration of all contaminants measured. Groundwater and soil showed low ammonia nitrogen with a maximum value of 2 mg.L−1. Elevated chloride levels were detected in all matrices studied. In soil depth, the concentration varied ​​between 17 and 1270 mg.L−1 and in groundwater between 843 and 3,252 mg.L−1. Results suggest the migration of leachate components through the local soil. The concentration of total organic carbon measured in soil was of 10–982 mg.L−1, suggesting its natural presence. [ABSTRACT FROM AUTHOR]

The contamination of heavy metal in leachate was investigated at various sites with different solid waste management, namely an open dump, controlled dump, and sanitary landfill. The results indicated that all four heavy metals investigated (cadmium, lead, mercury, and manganese) were present in the leachate at all solid waste management sites. The highest cadmium and lead concentrations were each observed in open dump leachate samples, while the highest manganese and mercury concentrations were each observed in controlled dump leachate samples. [ABSTRACT FROM AUTHOR]

Halting the unsustainable solid waste disposal practices has been a concerning issue due to the severe implications to public safety, health and the adverse impacts on the environment.As such, in lower-income nations where dumpsites are the leading waste disposal structures, there is an ongoing effort to upgrade to more sustainable options. In Mozambique, a semi-aerobic landfill, also known as the Fukuoka method, was selected to replace the key dumpsite located in the capital. Nevertheless, limited information is available on the prospective environmental impacts resulting from the planned upgrade. This study aims to assess the greenhouse gas emissions from Hulene dumpsite in Maputo City, Mozambique, operating under anaerobic conditions and the changes after the upgrade to a semi-aerobic landfill, employing the Intergovernmental Panel on Climate Change (IPCC) methodologies. The emissions from 1980 to 2030 in the dumpsite totaled 2,455 Gg CO2-eq, which 568 Gg CO2-eq corresponds to the contribution from open-burning activities. On the other hand, emissions for the semi-aerobic landfill from 2020 to 2030 were 685 Gg CO2-eq, 40% less than the total emissions from open dumping in the same period. The findings suggest that transitioning to a semi-aerobic landfill can significantly reduce GHG emissions, improve the local environment, and protect human health.

• Investigated the mode of collapse of the dump and the triggering factors. • Deployed drone-assisted sensors and other instrumentations. • Worked out a short-term plan for the control of further collapse. • Managed the collapsed dump without further slope failures successfully. • Could be replicated in other landfills to avoid calamities. Meethotamulla open dump (MOD) of Sri Lanka that has received about 290,000 metric tons of mixed MSW annually collapsed on 14th April 2017 with massive devastation. An integrated approach was attempted to control further collapse with the deployment of drone-assisted and stand-alone instrumentation. The collapsed dump was analyzed for attributes, including contours, heights, wetness, temperature levels, tension cracks, landfill gases, fire, explosion, and asphyxiation hazards with 24-h surveillance after one day of the collapse. The mode of MOD failure was implicated to be deep-seated (rotational) slope failure. A short-term plan, consisting of 12 activities was prepared and successfully implemented. The activities of the short-term plan were carried out at the dumpsite until the water level fluctuations <5 cm, inundation of the toe area receded completely, the horizontal displacement of surface markers <20 mm, lower explosive levels of CH 4 and CO less than 5 and 12%, respectively, O 2 level improved up to 21%, and temperature variation of the collapsed face <2 °C. The short-term plan was halted when the factor of safety for slope failure of the critical face improved from 0.807 to 1.286 ensuring no signs of a subsequent collapse of the MOD. An early warning system was established in the case of an imminent collapse. This integrated approach, to our knowledge, is the first study instituted, and this holistic management effort could be easily replicated to avoid disasters from slope failures of landfills or open dumps that may occur elsewhere. [ABSTRACT FROM AUTHOR]

Municipal solid waste (MSW) management is a major concern in Indian cities. This work rigorously assesses the relative costs and the environmental and health benefits of alternative MSW management methods. Management of MSW over the next 20 years for the city of Greater Mumbai was considered. A generic model was developed to determine the costs for (i) dumping on open ground, (ii) sanitary landfill without leachate treatment, (iii) landfilling with leachate treatment and (iv) regional composting and landfilling. LandGEM was used to quantify the gaseous emissions from landfill, while emissions from leachate and composting were taken from literature. The life cycle impact model of one tonne of MSW was developed using OpenLCA software and the International Reference Life Cycle Data System (ILCD) 2011 method was used for impact assessment. The cost of disposal of one tonne of waste was found to be INR344 (US$5.17), INR741 (US$11.13) and INR1367 (US$20.53), respectively, for the first three scenarios. As compared to open dumping, landfill gas flaring reduced the global warming potential by 32% and leachate treatment reduced freshwater ecotoxicity and total human toxicity marginally, by 20% and 60%, respectively. Composting-landfilling was the most preferred option, with a cost of INR531 tonne−1 (US$7.97), leading to a reduction in global warming potential by 79% and a slight decrease in freshwater ecotoxicity by 64%. Further, emissions due to accidental fires were also quantified. The study provides valuable insights for the selection of MSW management options for large metropolitan cities in developing countries. [ABSTRACT FROM AUTHOR]

In Mexico, open dumps that are maintained by the municipality but provide no covering of waste are not uncommon. Further, disposal at these sites is often performed by burning. The aim of this study was to determine the leachate plume from an open dump located in a depositional deltaic environment, with arid climate, low rainfall and where the water table is about 2 m below the surface. The methodology comprised analysis of groundwater monitoring wells and geophysical and geochemical prospecting techniques. The 3D geoelectric interpretation shows a typical area of these depositional environments with low resistive values (10–20 Ω-m) associated with the presence of sands and clays interbedded. However, there is a very low resistivity zone associated with the dump’s impact which reaches values below 5 Ω-m, and it is located where the disposal and burning of wastes occurred. Another zone with values above 16 Ω-m appears as a limit for the advance of the saline. This is interpreted as a sandy lenses area. These sandy lenses with higher porosity transport aquifer’s water. Thus the dump is in direct contact by this conduct with clean groundwater. Piper diagrams constructed with the chemical data analysis reveal that the groundwater in the area corresponds to the chlorinated and/or sulfated sodium type, showing the impact caused by the dump. The monitoring well (NP8, on-site) with the highest dissolved solids content behaves anomalously and belongs to the more conductive zone according to the geoelectric profiles. The subsoil geochemical behavior is influenced by the seasonal water table variations provoking the dissolution of burned and unburned wastes, but the effects of slow flows in the direction of the regional flow are not discarded. Although the most impacted area within the dump is characterized to a depth of 10 m, there is a slow flow in the direction of the regional flow that has been moving pollutants out of the dumpsite during its almost 20 years of operation. The results of this study provide valuable information for the authorities to carry out an appropriate restoration project. [ABSTRACT FROM AUTHOR]

In developing countries, quantities of solid waste generation is increasing day by day and most of which is disposed off through landfilling and open dumping resulting into the release of significant quantities of GHG. CH 4 , the major gas produced by these activities, is known to cause global warming. The paper reports the estimates of CH 4 calculated by using IPCC Default, FOD method and LandGEM model, version 3.02 from Panki open dump site of Kanpur, India. The annual average CH 4 emission rates from Panki open dump site is found as 197.33, 24.27 and 25.14 Gg by IPCC Default method, FOD and LandGEM respectively for the period 2010-2030. The study reveals that IPCC Default method over estimate the result therefore it is not recommended for open dump site. however, LandGEM is recommended over FOD method for open dumps due to the fact that [a] estimates of CH 4 emission is very near to GHG emission by FOD method [b] simplicity in model parameters [c] avoidance of over estimation, if parameters are calculated as per the actual site conditions. So the present study reveals that LandGEM provides better estimation compared to other method and the CH 4 emission rate is found as 25.14 Gg/year for the Panki open dump site, Kanpur. The assessment of methane emission potential reveals the fact that upgrading the open dumps into landfill increases the methane emission rates and their utilization potential and adding the landfill to fill the future needs and utilization of landfill gases. [ABSTRACT FROM AUTHOR]

Leachate quality varies depending on many factors such as the depth and the content of solid waste, seasonal variations in solid waste, and the duration of storage of solid waste; design and operation of storage space; geological and hydrogeological characteristics of storage area; and environmental interaction of leachate, which affect each other. One of the two major sources of leachate is the moisture content of the waste stored and the other is the mass of water entering the storage area from outside. A major part of the mass of water entering the storage area from outside is the infiltration of rain water through the storage area. The purpose of this study is to assess the seasonal variation in leachate of Gümüshane (Central) open dump area using the 'water balance method' for the determination of the factors affecting the seasonal variation in leachate of landfill, which particularly holds a higher risk of contaminating the environment. In addition, some of the measures to be taken in solid waste storage areas in order to minimize the mass of leachate are presented. [ABSTRACT FROM AUTHOR]

The main focused of this study is to investigate the variability of parameters involved in the estimation of an index known as leachate pollution index (LPI) as well as the contamination potential of pilot scale landfill lysimeter using LPI. LPI is a quantitative tool by which the leachate pollution data of landfill lysimeter can be reported uniformly. The parameters required to calculate LPI from landfill lysimeter were discussed in terms of their variations over time and their significance has been highlighted in the context of LPI by the author. The LPI values of one open dump lysimeter having two distinct operating systems and two sanitary landfill lysimeter had been calculated in this study. Result reveals that among the four lysimeter operating system, collection system of open dump lysimeter had the highest LPI, while detection system had the lowest LPI. Moreover, collection system of open dump lysimeter had the highest LPI than the other lysimeter operating system. Here, it was observed that LPI had been decreased in relation to the increasing of elapsed period of MSW deposited in landfill lysimeter. LPI can be used as a tool to assess the leachate pollution potential from landfill lysimeter particularly at places where there is a high risk of leachate migration and pollution of groundwater. The LPI can be a useful tool to monitor the leachate trends over the lifetime of landfill site, and thus can help to take necessary decisions as deem fit. Moreover, the LPI for this landfill lysimeter has been compared with the LPI estimated for treated leachate as per the Indian Standards. Finally, it can be concluded that LPI for landfill lysimeter was significantly high and proper treatment will be necessary before discharging the lysimeter leachate into the water bodies. [ABSTRACT FROM AUTHOR]

Geo-environmental assessment and geophysical investigations were carried out over the only functional municipal solid waste disposal site of the city of Addis Ababa, Ethiopia, known locally as Koshe. The accumulated wastes from Koshe have impact on the surrounding human and physical environment since the disposal site was not designed. The study deserves emphasis because the city of Addis Ababa currently obtains a considerable portion of its domestic water supply from a well field developed not much farther from and along a groundwater flow direction in relation to the waste disposal site. It was found out that the leachates from the site contain high concentration of biological oxygen demand, chemical oxygen demand, chloride and sulphate besides high concentration of cobalt, nickel and zinc in the surrounding soils. The geophysical results have mapped weak zones and near-vertical discontinuities that could potentially be conduits for the leachate from the wastes into the deep groundwater system. Further, a zone of potential leachate migration from the landfill was identified from the electrical models; the location of this zone is consistent with the predicted direction of groundwater flow across the site. The results further suggested that the open dump site tends to cause increasing amount of pollution on the surrounding soil, surface and ground waters. Furthermore, it was observed that the Koshe waste disposal site has grown beyond its capacity and the poor management of the open dump landfill has reduced the aesthetic value of the surrounding environments. The need to change/relocate the existing waste disposal site to a more suitable and technologically appropriate site is emphasized. [ABSTRACT FROM AUTHOR]

Environmental policy in waste management leads to increasing interest in developing methods for waste disposal with minimum emissions of greenhouse gases and minimum environmental impacts.Open dumping, landfilling and modern waste combustors (MWCs) are the prevalent solid waste disposal practices in many countries. Surveys on the disposal sites revealed the presence of numerous landfills ,open dumps and waste combustors. Greenhouse gas emission potential at these sites can be estimated by different methods. The purpose of this paper is to establish a more robust technique for determining the potential of gas emissions from municipal solid waste and to use those results in a life cycle assessments that determines the GHG impacts of modern MWCs and landfills. Methane emission potential at these sites was estimated by three methods. Results of the Intergovernmental Panel on Climate Change (IPCC) method, Landfill Gas Emission model (LandGEM), and closed flux chamber technique were compared. For the facilities analyzed , the methane emission potential of 18.94 Gg/yr using the IPCC method was higher than the estimations of the LandGEM and closed flux chamber method of 5.95 Gg/yr and 5.33 Gg/yr, respectively. From the point of view of nitrous oxide (N2O) emissions, waste incineration and waste co-combustion are acceptable methods of waste disposal. Two factors are important for attaining low NOx emissions from waste combustion , particularly for waste with higher nitrogen content (e.g. sewage sludge, leather, etc.): temperature of incineration over 9000C and using of modern incinerators with selective catalytic reduction (SCR) or selective noncatalytic reduction (SNCR) deNOx facilities. The catalysts used in SCR based facilities are among others Fe-zeolite and V2O2. This catalysts have high N2O decomposition (and SCR) activity with good hydrothermal stability. This data are essential to assess the potential need of abatement measures to limit N2O emissions in future operation of waste incineration plants. [ABSTRACT FROM AUTHOR]

The paper presents the results of the monitoring of underground water and superficial lagoons nearby the São Pedro da Aldeia (RJ, Brazil) open dump. Six piezometers, three lagoons and one water hole were utilized to obtain the samples. Results of field measures of pH, conductivity, redox potential and laboratory analyses of Cl-, Na+, K+, e NH4 + are presented. Results show the open dump influence on superficial and underground water, after 17 years of operation, reaches between 150 and 200m of distance, with no attenuation. [ABSTRACT FROM AUTHOR]

The increasing municipal solid waste (MSW) generation along with the high fraction of organic waste and a common disposal of open dumping is the current scenario in many areas in Thailand. As a response to this problem, the country’s Pollution Control Department (PCD) aims to reduce the MSW generation rate to less than 1 kg/capita/day, increase the collection efficiency, and improve the recovery of recyclables. For many years, more than 60% of the solid waste disposal system in Thailand has been carried out by open dumping. According to the survey conducted by this study, in 2004 there were 425 disposal sites (95 landfills; 330 open dumps) in Thailand and an estimated methane emission of 115.4 Gg/year was generated based on this practice. It has been estimated that the anticipated methane emission in Thailand will rise from 115.4 Gg/year to 118.5 Gg/year if the largest open dumpsites in provinces with no existing landfill are upgraded to sanitary landfill; and it will increase to 193.5 Gg/year if the existing sanitary landfill is upgraded to integrated waste management facilities. Moreover, Bangkok metropolitan have the highest methane emission (54.83 Gg/year) among all the regions in Thailand. The methane emission forecast of 339 Gg/year by 2020 (based on LandGEM methodology) provides a stimulus to create a comprehensive plan to capture and utilize methane as an energy source. [ABSTRACT FROM AUTHOR]

This paper presents a general overview of the current municipal solid waste management in Gümüşhane Province, Turkey. In the study conducted between March 2004 and February 2005, the composting parameters (moisture content, total organic carbon, total nitrogen and pH), organic matter content and the heavy metal concentrations (Cd, Cr, Cu, Ni, Pb, Zn, Fe, Mn, Co) of the green wastes sorted from the mixed municipal solid waste were determined and evaluated. The analytes were determined with a relative standard deviation lower than 6% in all samples. The organic fraction of biological origin made up about 30% of the total amount of the municipal solid waste. Moisture con- tent was 78%, organic matter content was 92.1%, C/N ratio was 21.6/1 and pH was 4.73. Heavy metal concentrations of the green wastes mixed with domestic wastes were found to be higher than the separately collected green wastes. Heavy metal concentrations of the green wastes from the open dump were determined to decrease in the following order: Fe>Mn>Zn>Cr>Cu>Pb>Ni>Cd>Co. [ABSTRACT FROM AUTHOR]

Cities in Mexico, as other cities around the world, face the serious problem of environmental pollution, caused mainly, by the inadequate and inefficient final disposal of their generated solid and liquid waste. An analysis of one stage of the municipal solid waste (MSW) cycle in Mexico is given in this paper; presenting the results of research in four cities. Four case studies, where the sanitary landfill and the uncontrolled dump, with varying degrees of management, are used as the final disposal for MSW are presented. [Copyright &y& Elsevier]