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Landfill is the main method for disposing of municipal solid waste (MSW). However, landfill instability destruction accidents occur frequently, and the instability is influenced by multiple factors. Due to the complex composition of MSW and its obvious heterogeneous properties, landfill stability is the most significant engineering challenge in landfill operations. This paper has provided a review about status quo of MSW disposal and researched the impact factors of MSW landfill stability through extensive literature research. In view of the landfill process and specific heterogeneity of MSW, a finite element model about spatial changes in engineering properties on MSW body has been proposed. Then the sensibility analysis of the engineering properties on heterogeneity municipal solid waste body stability has been conducted, and the influence curves for the safety factors of the MSW body have been proposed. Finally, suggestions have been proposed that can provide technical support and can serve as a reference for the design, operation, and maintenance of MSW landfills. [ABSTRACT FROM AUTHOR]

[Display omitted] • FTIR, mass reduction, and SEM reveal the effects of the digestion solution. • 30 % H 2 O 2 is the optimal digestion solution, which is the least harmful to MPs. • Elucidating the composition of MPs in landfills: PE, PP, PS, and PET dominate. The landfill is one of the most important sources of microplastics (MPs). The pretreatment method is a precondition of microplastics study for the presence of complex substances in landfills. Therefore, it is essential to examine the impact of different pretreatment methods on the microplastics detection. A literature review and a comparison experiment on digestion solutions were performed to establish a comprehensive identification method for MPs in landfills. When exposed to of 30 % H 2 O 2 , minimal mass reduction of PE, PP and PET were 4.00 %, 3.00 % and 3.00 % respectively, and the least surface damage was observed in MPs, while exhibiting the most optimal peak value for infrared spectral characteristics. It is demonstrated that the effect of 30 % H 2 O 2 dissolution was superior compared to 10 % KOH and 65 % HNO 3. The method was subsequently utilized to investigate the distribution of MPs in a landfill. The dominant MPs were polyethylene (PE, 18.56–23.91 %), polyethylene terephthalate (PET, 8.80–18.66 %), polystyrene (PS, 10.31–18.09 %), and polypropylene (PP, 11.60–14.91 %). The comprehensive identification method of "NaCl density separation + 30 % H 2 O 2 digestion + NaI density separation + sampling microscope + Mirco-FTIR" is suitable for the detection of MPs in landfills. [ABSTRACT FROM AUTHOR]

In order to explore the variation law of geotechnical properties of landfill humus soil with landfill depth, taking humus soil with different landfill depths in old landfills as the research object, the method of combining laboratory test and theoretical analysis was used to study the physicochemical properties and the mechanical properties of humus soil. The results show that with the increase in landfill depth, the proportion of humus soil in municipal solid waste and the physicochemical properties of humus soil such as particle size distribution, organic matter content, specific gravity and pH value of the leaching solution all change, which further affects the mechanical properties such as compressive strength, shear strength, saturated permeability and compressibility. These conclusions provide theoretical reference for the resource utilization of humus soil. [ABSTRACT FROM AUTHOR]

Landfilling is the most common and cheapest method of waste management practice in India. Municipal Solid Waste Landfills (MSWL) became a nuisance affecting the health, hygiene, sanitation and aesthetics of the surrounding area. Aggregates occupy almost 70% of concrete, so replacing waste materials with them could be a rewarding choice. In the current work, an experimental investigation is being carried out to test the addition of MSWL as a substitution with fine aggregate for concrete production. Out of the different aged samples available at the dumpsite, the most aged sample is chosen for experimental investigations according to the basic physical properties. Concrete mixes, with 0%, 4%, 5%, 7% and 10% partial replacement of fine aggregate with MSWL are tested for mechanical properties such as compressive strength, split tensile strength, flexural strength, and nondestructive test and have proved to be a partial substitute for fine aggregate. Durability studies such as water absorption, acid attack and sulphate attack also gave better experimental proof for the sustainable reuse of this waste material. The research reveals 5% replacement is the optimum considering all the test result values. The paper leads to advanced research for the suitability of the material in the construction industry. [ABSTRACT FROM AUTHOR]

The Jigongshan Mountain Tunnel in Shenzhen China is 4.6 km in length and designed to cross underneath the Xiaping Municipal Solid Waste Landfill. The estimation of the in situ stress field along the tunnel, particularly under the Xiaping landfill, has posed significant challenges. In this study, an integrated strategy comprising multisource information analysis and intelligent back analysis was developed to predict the in situ stress of the study region. First, the regime of in situ stress was estimated based on multisource information, including geological history, geological structure, topography, rock type, joint, and measured stress. Then, multiple linear regression and particle swarm optimization (PSO) method coupled with extreme learning machine (ELM) method were introduced into the intelligent back analysis to identify the orientation and magnitude of the in situ stress along the tunnel. By simultaneously considering the effects of gravity, tectonic stress, rock and fault parameters, and landfill load on the in situ stress, the sum of squares for error in simulation of in situ stress significantly decreases by 23%. Finally, the accuracy of the predicted in situ stress field and the reliability of the proposed integrated method were substantiated through a comprehensive comparison between the simulated and measured rock displacement acquired during the tunnel excavation process. The characteristics of the in situ stress along the tunnel and under the landfill were successfully identified. The landfill load predominantly influences the vertical stress under the landfill, while it does not alter the three-dimensional state of stress. This study serves as a valuable reference for identifying the in situ stress in regions with varying upper loads and limitations on conducting field measurements. [ABSTRACT FROM AUTHOR]

Municipal solid waste disposal sites act as sources of secondary pollution of the environment with waste destruction products that undergo further chemical and biochemical transformations. The research deals with the issues of quantitative assessment of greenhouse gases and persistent organic pollutants formation within municipal solid waste landfills. It uses such methods as mathematical models of pollutants formation inside a municipal solid waste landfill body, namely methane and persistent organic pollutants formation. Bioorganic substance forming the major part of municipal solid waste generates methane, carbon dioxide and other compounds; presence of chlorine in various compounds included in the composition of waste causes unintentional formation of persistent organic pollutants, in particular PCDD/F. The article presents the results of measurements of methane formation (according to the National Gas Formation Model), carbon dioxide and non-methane volatile organic compounds formation (according to the LandGEM model) with relation to the conditions of the municipal solid waste landfill «Dalnytsky Kariery» that accepts waste from the Odesa industrial-and-urban agglomeration. It shows the municipal solid waste landfill as a significant source of greenhouse gases the amount of which increases rapidly under the conditions of long-term operation and constant delivery of waste. The discrepancy in the results of methane formation measurements indicates the need to adapt the LandGEM model that matches the Ukrainian conditions. It would allow determining a wide range of atmospheric polluting substances. The author's design determines the formation of persistent organic pollutants as exemplified by PCDD/F. The measurements showed that landfills act as a significant source of unintentional formation of PCDD/F, 99% of which accumulate inside a landfill itself. They also indicated that, under the conditions of a constant delivery of waste to a landfill, there is a rapid increase in the amount of PCDD/F formed, even with consideration of the half-life period. The landfill itself is considered as a main source of unintentional formation of PCDD/F within the whole Odesa agglomeration.

Leaching of per- and polyfluoroalkyl substances (PFAS) during the post-consumer disposal of food contact materials (FCMs) poses a potential environmental threat but has seldom been evaluated. This study characterized the leaching behavior of PFAS and unidentified precursors from six common FCMs and assessed the impact of environmental conditions on PFAS release during disposal. The total concentration of 21 PFAS ranged from 3.2 to 377 ng/g in FCMs, with PFAS leachability into water varying between 1.1–42.8 %. Increasing temperature promoted PFAS leaching, with leached nine primary PFAS (∑ 9 PFAS) reaching 46.3, 70.4, and 102 ng/L at 35, 45, and 55 ℃, respectively. Thermodynamic analysis (∆G>0, ∆H>0, and ∆S<0) indicated hydrophobic interactions control PFAS leaching. The presence of dissolved organic matter in synthetic leachate increased the leached ∑ 9 PFAS from 47.1 to 103 ng/L but decreased PFBS, PFOS, and 6:2 FTS leaching. The total release of seven perfluorocarboxylic acids (∑ 7 PFCAs) from takeaway food packaging waste was estimated to be 0.3–8.2 kg/y to landfill leachate and 0.6–15.4 kg/y to incineration plant leachate, contributing 0.2–4.8 % and 0.1–3.2 % of total ∑ 7 PFCAs in each leachate type. While the study presents a refined methodology for estimating PFAS release during disposal, future research is needed on the indirect contribution from precursors. [Display omitted] • Leached percentage of short-chain PFAS to water was > 2x than long-chain PFAS • A 10 ℃ rise within 35–55 ℃ increased ∑ 9 PFAS leaching by ∼50 % • DOM enhanced ∑ 9 PFAS leaching but inhibited leaching of some PFAS compounds • Takeaway FCM released ∼1.6 % and ∼1.0 % ∑ 7 PFCAs to landfill and incineration leachate [ABSTRACT FROM AUTHOR]

The distribution of leachate directly impacts the safety and stability of the landfill, so it is important to research the distribution of seepage characteristics and migration patterns of leachate. The study aims to investigate the impact of heterogeneous permeability distribution and clogging of the drainage layer on leachate transportation in landfills. To achieve this, a heterogeneous transient seepage model was developed. Results showed that when considering the heterogeneous permeability of the waste in the buried depth direction, the maximum perched water level was higher, which is not conducive to the safety and stability of the landfill. Taking Xi’an Jiangcungou Landfill as a research object, the maximum perched water level of each waste layer was higher compared to the homogeneous condition when considering the landfill process and heterogeneous permeability. The differential value ranged from 0.08 m to 1.88 m. Furthermore, the calculation results obtained from the heterogeneous seepage model were found to be in good agreement with both actual field data and referenced survey data, thus confirming the reliability of the model. These research findings not only offer technical support but also provide a solid theoretical foundation for leachate level control and safety and stability assessments.

[Display omitted] • Soil-like material cannot be used for agricultural utilization with HMs contamination. • Zn with main forms of acid-soluble and reducible state had the highest content and mobility. • Cu & Pb with main form of oxidizable state, Cr & Ni with oxidizable & residual state were stable. • Dissolved organic matter had a high concentration of protein-like materials in soil-like material. • Dissolved organic matter in soil-like material is dominated by protein-like materials. • Protein-like materials enhance heavy metals' mobility and environmental risks. Soil-like material (SLM) mined from municipal solid waste (MSW) landfills can be used as nursery cultivation soil, landfill cover, and as a building material. However, SLM utilization is restrained by heavy metal (HM) contents whose speciation and migration are influenced by their dissolved organic matter (DOM) content. Therefore, the properties of aged refuse and the correlation between DOM and HM forms were studied using samples from different types of MSW landfills. The dominant components of aged refuse were SLM (18.80%–83.51%) and plastics (11.17%–65.51%). The moisture, organic matter, and pH ranged from 29.55% to 57.92%, 15.70%–57.68%, and 7.84–8.51, respectively. The Zn content was highest (455.48–1379.27 mg/kg) in the SLM, followed by Cu (96.29–428.90 mg/kg), Cr (49.10–236.21 mg/kg), Pb (53.52–222.71 mg/kg), and Ni (20.92–39.10 mg/kg). The SLM cannot be used for agriculture because the HM contamination exceeds the multiple of 0.07–7.99. Zinc in the acid-soluble state and reducible state had the highest mobility in SLM. However, Cu and Pb, mainly in the oxidizable state, and Cr and Ni, in the oxidizable and residual states, were relatively stable. In the sanitary and simple MSW landfills, the average proportion of protein-like materials decreased from 84.44% to 82.61% and from 65.58% to 55.94%, respectively, as the landfill depth increased. Both the acid-soluble and oxidizable HM states and all forms of Zn in the SLM were significantly positively correlated with tyrosine-like materials (r = 0.58*–0.87**). Protein-like materials may enhance the mobility of HMs. [ABSTRACT FROM AUTHOR]

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°. [ABSTRACT FROM AUTHOR]

Slope failure in municipal solid waste (MSW) landfills is a common environmental disaster that poses serious ecological and health risks. Landfill slope stability (SS) is sensitive to leachate levels and gas pressure (GP) caused by the degradation of organic material, but the extent of these combined effects remains poorly understood. In this study, a simplified landfill GP calculation method is presented and a circular slide method that considers the combined effects of leachate and GP is established. The results show that the landfill GP is mainly affected by the gas production rate, gas conductivity of the solid waste (SW), and landfill depth. The safety factor of landfill SS is also significantly lower when GP is considered. The distribution of GP is affected by the depth of the failure circle and SW. Landfill slope instability can be explained by localized damage caused by GP breakthrough of the filled SW. This study probably provides important guidance for the design, operation, and management of MSW landfills. [ABSTRACT FROM AUTHOR]

The bioindication method is used to assess the general vital condition of coniferous phytocoenoses growing at different distances (0.25, 0.75, 1.4, 2.4 km) from municipal solid waste landfill Zhiroshkino (Moscow region, Domodedovo district). The object of study is ordinary pine ( Pinus sylvestris L. ), as the most sensitive to the action of pollutants and often used in Russia phytoindicator. The state of generative organs (number of old and new cones, increase of shoots), defoliation and depigmentation class were selected as diagnostic indicators; the category of vital condition was determined and the stand state index was calculated. It was found out that closed objects of production and consumption waste disposal have a negative impact on the stand of an ordinary pine tree. Thus, trees growing at a distance of 250 m from the landfill within its sanitary-protective zone, according to the stand status index are characterized as strongly weakened. At the distance from the waste landfill the tendency of increasing the number of healthy trees in the structure of phytocoenosis was recorded, and their vital condition was assessed as weakened by the growing stock. The index of stand condition, classes of defoliation and depigmentation, the number of generative organs have reached the control values (Kuzminsky Forest Park, the prevailing category of weakened trees) at the distance of 2.4 km from the disposal site. However, the values of these indicators are much lower than the background ones (Prioksko-Terrasny Reserve, the prevailing category healthy trees) for all studied coniferous phytocoenoses. The conclusion is made about the possibility of bioindication method using morphological features of ordinary pine as an express method of assessment of negative impact of waste disposal objects on the environment.

[Display omitted] • Cr and Zn were the main heavy metal contaminations in the soil of MSW landfill. • Soil heavy metal contamination was more obvious in the non-sanitary landfills. • Soil Cd concentration had a significant negative correlation with landfill age. • Soil Pb and As concentrations had a significant positive correlation with rainfall. • Soil heavy metal contaminations at the bottom was more serious than outside. The environmental risk assessment and the factors influencing heavy metals (HM) in the soil at the municipal solid waste landfill sites (MSWLs) were studied by literature review, field survey, and statistical methods. The results indicated that the dominant HM contamination in the soil at the MSWLs was caused by chromium (Cr) with the Nemero index values (PI) from 22.7 to 44.3 and zinc (Zn) with the PI from 0.7 to 9.8. There were significant differences in the Cr, mercury (Hg), lead (Pb), Zn, and arsenic (As) concentrations between soil samples from sanitary and non-sanitary landfills (NSLs) where HM contamination (PI = 10.9) was more obvious. As (CRA As = 2.35 × 10-4) and cadmium (Cd) (CRA Cd = 1.45 × 10-4) posed potential carcinogenic health effects. The soil Cd concentration had a significant negative correlation (r = -0.476**) with the landfill age. The soil As concentration had a significant positive correlation (r = 0.472**) with rainfall in NSLs. There were significant differences in the As (P = 0.042) and copper (Cu) (P = 0.042) concentrations between soil samples from the surrounding areas of MSWLs and the base where soil had higher HM concentrations. For the efficient prevention of HM ecological risk, a scientific site selection, undamaged coverage and anti-seepage systems, standardized management, and ongoing monitoring are required. [ABSTRACT FROM AUTHOR]

The effectiveness of earthen liners in preventing the migration of heavy metals (HM) from the landfill requires the study of the transport parameters of HM and the determination of the optimum thickness of the earthen liners that can effectively retain the HM within their permissible concentrations during the lifetime of a landfill. The aim of this study is to investigate the transport behavior of four HM (cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn)) through an earthen liner via physical and numerical modeling. Subsequently, the optimum thickness of earthen liners required to prevent the breakthrough of HM for different assumed landfill life expectancies was assessed from the long-term migration profiles of HM. In general, the extent of HM migration in two types of compacted residual soil liners, which were clayey sand and silty sand, followed the sequence of Zn < Cd < Cu < Pb. It is observed that the extent of HM migration was greater in the compacted silty sand sample attributed to its higher porosity and lower HM adsorption capacities. The numerical simulations results further revealed that the optimum thickness required for compacted clayey and silty sand liners to retain the four studied HM within their regulatory threshold values for a period of 100 years were 1 m and 1.9 m, respectively. Considering the higher mobility and more stringent allowable concentration of Cd, Cd can serve as a key indicator of early HM contamination caused by leachate migration from Malaysian municipal solid waste landfills. [ABSTRACT FROM AUTHOR]

• The MSW generation is related to social index, economic index and population index. • The Grey Relational Analysis method can improve the prediction performance accuracy. • The GRA-LSTM model precisely and accurately predict the MSW generation in Beijing. • Advice for urban development are proposed from the MSW source and the MSW disposal. Achieving accurate prediction of the Municipal Solid Waste (MSW) generation is essential for the sustainable development of the city. This paper selects Beijing as the research object, building a neural network model based on Grey Relational Analysis and Long and Short-Term Memory (GRA-LSTM), and choosing 14 influencing factors of MSW generation as the input indicators, to realize the effective prediction of MSW generation. Then this study obtains the landfill area in Beijing by using the aforementioned prediction results and the calculation formula of the landfill. Firstly, the GRA method is used to sort the influencing factors of the MSW generation for obtain the key influencing indexes. Secondly, the LSTM model is used to learn features of the key influencing indexes. Finally, the area of Beijing landfill is estimated by the calculation formula of landfill area. The results show that, first of all, the MAPE value of the GRA-LSTM combined model established in this paper is 7.3, and the prediction performance of this model is better than the other seven structural methods. Secondly, the area demand for landfills in Beijing shows an upward trend. At last, this paper put forward relevant suggestions to achieve sustainable urban development and deal with the increase in the MSW generation and the demand for landfills. [ABSTRACT FROM AUTHOR]

The concentrations of Fe, Mn, Cu, Zn, Pb, Cd, and Ni were studied in the brown algae Sargassum miyabei Yendo and S. pallidum (Turner) C. Agardh collected in Ussuri Bay, Sea of Japan, from 2001 to 2018. The degree of heavy metal pollution in different parts of the bay was assessed by comparing the actually measured concentrations of the metals in algae with the upper threshold values of their background ranges of concentrations (CUT). The coefficient of metal contamination risk for algae (KR) was calculated as the ratio of the metal concentration in algae to CUT. In 2016–2018, the KR values for Cd and Ni reached 1.7; for Zn, 2.0; for Fe, 3.1; for Mn, 7.2; for Pb, 12.3; and for Cu, 15.0. The maximum concentrations of most elements were recorded from the Sargassum algae collected off the Vladivostok municipal solid waste landfill operated in 1967–2010. In this part of the bay, the major pollutants in 2016–2018 were Pb and Cu; the accompanying pollutants were Zn, Mn, Fe, and Ni. [ABSTRACT FROM AUTHOR]

Effective management of municipal solid waste (MSW) is essential for the conservation of ecosystems in the Qinghai-Tibetan Plateau (QTP). Considering the landfill is the major method of MSW management, the factors influencing groundwater contamination near MSW landfill sites in the QTP were studied, based on field investigations, environmental impact assessment, and meteorological and hydrogeological analyses. Results indicated that the groundwater was contaminated heavily by nitrate (PI = 7.5), particularly in the landfill without an anti-seepage system, followed by nitrite (PI = 3.5) and heavy metals including arsenic (PI = 4.1) and hexavalent chromium (PI = 2.8). Total hardness, total dissolved solids, nitrate, and lead in the groundwater near the investigated landfill sites were significantly different between the monsoon and the cold seasons. Both the rainfall infiltration and the leachate infiltration were considerably limited by environmental characteristics in the QTP, including high evaporation, low rainfall, and the presence of permafrost. Soil sample contamination near landfill sites was considered as moderate (28.6% of the soil samples) and moderate to heavy (71.4% of the soil samples), based on the geoaccumulation index of mercury. However, comparatively low generation and concentrations of leachate and good topsoil quality (PI = 0.84) reduced the quantity of pollutants infiltrating into the groundwater. The alkaline leachate (pH = 7.45–9.23) and soil (pH = 7.08–8.72) also considerably decreased the concentrations of contaminants dissolved in the infiltrated rainfall and leachate. Additionally, low groundwater level can delay preferential flow and enhance attenuation. Therefore, the groundwater contamination near the landfill sites was simply point pollution, which was influenced by leachate, soil, climate, and hydrogeology characteristics in the QTP. The anti-seepage system is a potential strategy for use in the prevention of groundwater contamination by MSW landfills in the QTP.

Ammonia inhibition of anaerobic waste degradation has been extensively investigated on a laboratory scale. It is hence well known that at ammonium levels above 2500 mg/l, methanogenic bacteria are inhibited, which leads to both reduced methane (CH4) production and increased organic pollution of the leachate. In the present paper, and for the first time, data on a full-scale landfill indicating ammonia inhibition of waste degradation is presented. The leachate of the landfill is characterized by extremely high concentrations of chloride (up to 70,000 mg/l) and ammonium–nitrogen (up to 20,000 mg/l). These high pollution levels are explained by the following facts: first, the landfill is located in an arid climate (annual precipitation of 200 mm), resulting in low fresh water infiltration; and second, leachate or concentrate resulting from reverse osmosis treatment at the site has been recirculated. The high ammonium levels obviously caused inhibitory effects on the anaerobic degradation, which resulted in chemical oxygen demand concentrations in the leachate of far above 300,000 mg/l. Furthermore, a comparatively low level of landfill gas (LFG) generation and a shift towards higher carbon dioxide and lower CH4 contents in the collected LFG was observed. Based on the gas compositional data, the overall reduction in CH4 generation was assessed to be 50%. In order to reduce organic leachate pollution and to enhance LFG production at the site investigated, fresh (rain) water infiltration should be enhanced and the recirculation of leachate or treatment residues derived thereof should be terminated. [ABSTRACT FROM AUTHOR]

As the final stage of waste management, the landfill has long been a focal point. Yet, the operation does not go in accordance with approved regulation which results in polluting. In response to that, Integrated Risk-Based Approach (IRBA) was conducted. IRBA is a decision-making method in closing and rehabilitation of open dumping through environmental risk assessment. Evaluated aspects on IRBA comprise of the technical aspect, environmental impact, and social aspect (particularly impact for society). Considered parameters in IRBA analysis are categorized into three which are: location (20 parameters), waste (4 parameters), and leachate (3 parameters). This research is focused on the risk index of a landfill in Bali Province which covers 10 landfills spread in Bali Province. Two of them are Regional landfill which is Sarbagita Regional landfill and Bangli Regional landfill; the others are City/Regency landfill which includes Bengkala landfill, Temesi landfill, Peh landfill, Linggasana landfill, Sente landfill, Jungut Batu landfill, Biaung landfill, and Mandung landfill. The higher the risk index, the higher the risk of polluting the environment which implies the need for further action, either by closing or rehabilitating the landfill. The highest risk index reached in Bali Province is 664.8 by Sarbagita Regional landfill and the lowest is 420.7 by Bangli landfill. [ABSTRACT FROM AUTHOR]

Large quantities of municipal solid waste originating from households, workplaces, commercial facilities and from other non-production activities are generated around the world daily. Solid waste landfills and their improper management pose a major threat to the quality of the environment (air, water, soil) in Macedonia and in many other developing countries. The main problem of the solid waste landfills is the generation of the leachate and its free release into the environment. Leachate is a highly contaminated fluid that contains large amounts of dissolved solids and suspended solids from landfill waste. In the frame of this article the physical and chemical properties of the underground and surface water near the landfill with unselected waste, were analyzed. Based on the results of chemical oxygen demand (COD), biochemical oxygen demand (BOD), the concentration of the heavy metal ions and regarding the values of other physicochemical parameters examined in the water samples, the influence of the municipal solid waste landfill on the quality of the water resources in that area, can be determined. [ABSTRACT FROM AUTHOR]

Abstract In previous studies of municipal solid waste (MSW) landfill barrier systems, chemical oxygen demand has been found to be the key pollutant indicator when estimating the breakthrough time for. However, the leachate head in a municipal solid waste landfill can be very high (>10 m in some Chinese landfills). The key pollutant indicator could be different at different leachate heads. The leachate head will continuously change during the use of a landfill. Different pollutants have different transport characteristics in the leachate, so it is necessary to determine whether changes in the leachate head change the key pollutant indicator for identifying breakthrough in a landfill barrier system. In this study, numerical models were used to investigate transport of common leachate pollutants through four typical landfill barrier systems with different leachate heads. Chemical oxygen demand reached the breakthrough threshold before the other pollutants, irrespective of (1) the leachate head and (2) changes in the leachate head. It was therefore clear that the leachate head did not affect the selection of the key pollutant indicator for identifying breakthrough in a landfill barrier system. Graphical abstract Image 1 Highlights • The influence of the leachate head on the breakthrough time of the landfill liners was investigated. • The effect of the leachate head on the pollutant indicator selection for breakthrough was studied. • An effective method was established to provide a reference for design and management of landfills. [ABSTRACT FROM AUTHOR]

• A new landfill cover material containing biochar was examined for odor control. • Contribution of NH 3 to the total odor strength was less than H 2 S and VOSCs. • Odor RE was different between theoretical & measured odor concentrations. • Optimum running parameters differed for theoretical & measured odor concentrations. • Bacterial genera in the covers were identified for reducing odorous compounds. Odor problem has become a growing concern for municipal solid waste (MSW) operators and communities located close to landfill sites. In this study, nine laboratory-scale landfill reactors were used to simulate in-situ odor control by a novel landfill cover material consisting of biochar-added sludge compost under various operating parameters. Characterization of odor removal and microbial community in the cover layer under various operating parameters was conducted using gas chromatograph-mass spectrometry and 454 high-throughput pyrosequencing, respectively. Results showed that H 2 S (76.9–86.0%) and volatile organic sulfur compounds (VOSCs) (12.3–21.7%) were dominant according to their theoretical generated odor concentrations. The total odor REs calculated using the theoretical odor concentrations in the landfill reactors were different than using the measured odor values, which were ranked from high to low as: R6 > R5 > R7 > R4 > R8 > R9 > R3 > R2 > R1, showing the largest discrepancy of 25.3%. The optimum combination of operating parameters based on the theoretical odor concentration was different with that based on the measured odor concentrations. Moreover, although Firmicutes (12.21–91.48%), Proteobacteria (3.55–51.03%), and Actinobacteria (4.01–47.39%) were in general the three major bacterial phyla found in the landfill covers, the detailed bacterial communities in the cover materials of the simulated reactors varied with various operating parameters. Alicyclobacillus and Tuberibacillus showed positive correlations with the removal efficiencies (REs) of chlorinated compounds, H 2 S, aromatic compounds, volatile organic sulfur compounds (VOSCs), and organic acids. The correlations of Rhodanobacter , Gemmatimonas , Flavisolibacter and Sphingomonas were strongly positive with ammonia RE and relatively positive with REs of organic acids, VOSCs, and aromatic compounds. These findings are instrumental in understanding the relationship between the structure of microbial communities and odor removal performances, and in developing techniques for in-situ odor control at landfills. [ABSTRACT FROM AUTHOR]

The study was conducted to measure the emission from landfill in the years 2005–2011. The results are used to diagnose the emissions of CH4. The mean value of CH4 in vol. % in the collection wells ranged from 0 to 2.14 vol. % the mean concentration of CH4 in mg/m3 ranged from 0 to 25 251 mg/m3 the average concentration of CH4 in mg/Nm3 at the measuring and control points ranged from 2.2 to 24.1 mg/Nm3. CH4 emissions from the landfill do not exceed the reporting thresholds the landfill does not meet conditions for being included in the Integrated Register of Pollutants.

The monitoring that was carried out at the landfill specialized in leachate, groundwater and surface water. There were 6 sampling sites. The observed parameters were pH, BOD5, CODCr, conductivity. Leachate reached the high values in all observed parameters. Groundwater samples were collected at two monitoring wells and the sampling site (A, B, C). Surface water was collected from two sampling sites (D, E). The pH showed slightly acid values at all sampling points. The pH of surface water was slightly acid to neutral. Both BOD5 and CODCr values ​​remained stable over the reporting period. The average conductivity value at sampling points D, E remained constant. In line with the Czech National Standard ČSN 75 7221 “Classification of Surface Water Quality” sampling point D belongs to II Water Quality Class – slightly polluted water and sampling site E to Class I water quality – unpolluted water. The authors believe that the fluctuations occurring with regard to the values of certain samples were not caused by the operation of the landfill itself, but were a result of the intense agricultural activity nearby the landfill.

Multi-matrix environmental monitoring was used to evaluate the influence of a municipal solid waste landfill (Ginestreto, Emilia Romagna, Italy) on the level and distribution of heavy elements in the surrounding environment (air, soil and soil biota). Concentrations of As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, Tl and Zn were measured by inductively coupled plasma-mass spectrometry in transplanted lichens, topsoils and isopods. The highest accumulation levels found for Cd, Cr, Pb, Sb and Zn in lichens transplanted within the Ginestreto landfill. However, similar concentrations of these heavy elements were also found in lichens exposed in monitoring sites influenced by other man-made sources, such as vehicle traffic and truck movements. The fallout of heavy elements emitted by the landfill had low impact on their levels in topsoil: Cd, Cr, Pb, Sb and Zn showed higher contents in topsoil collected close to the landfill and a slight decrease in concentrations with increasing distance from the landfill. There was no variation in heavy element accumulation in isopods in relation to distance from the landfill. The results of this study indicate that the Ginestreto municipal solid waste landfill had limited impact on the environmental distribution of heavy elements, since accumulation and enrichment in lichens and topsoils were only detected close to the landfill, up to about 100 m from its border. [ABSTRACT FROM AUTHOR]

Przeprowadzono badania stężenia bioaerozolu pochodzącego ze składowiska odpadów komunalnych w Machnaczu w okresie jesiennym metodą zderzeniową. Do oceny zasięgu oddziaływania składowiska na otoczenie zaproponowano wykorzystanie własnej metody, opartej na wybranych mikroorganizmach wskaźnikowych: bakteriach z rodziny Enterobacteriaceae, bakteriach hemolizujących typu beta oraz drożdżach i grzybach drożdżopodobnych. Katalog wybranych mikroorganizmów wskaźnikowych nie pokrywa się ze standardową Polską Normą PN 89/Z-04111.01. Stanowi to o pewnej specyfice zastosowanej metody pomiaru. Taki wybór wskaźników pozwala bowiem nie tylko ocenić poziom zanieczyszczenia powietrza w obrębie samego składowiska, ale umożliwia także określenie zasięgu oddziaływania składowiska na otoczenie. Uzyskane wyniki pozwalają stwierdzić, że badane składowisko jest istotnym źródłem emisji i rozprzestrzeniania się aerozolu bakteryjnego i grzybowego pomimo prawidłowej eksploatacji i poprawnie prowadzonych procesów technologicznych składowania odpadów. Zasięg oddziaływania składowiska na stan sanitarny powietrza atmosferycznego ocenia się na 1000 - 1200 m, licząc odległość od ogrodzenia obiektu. Tak duża odległość może stanowić potencjalne zagrożenie dla okolicznych mieszkańców.

The methane (CH4) emissions from municipal solid waste (MSW) landfills in China in 2007 were estimated based on database of the three-dimensional emission factors matrix and point sources, by an IPCC recommended FOD (firstorder decay) model. The location, capacity and age of landfills constitute the three dimensions of the emission factors matrix, which were obtained by laboratory analysis and in situ investigation. Key parameters such as waste composition, degradable organic carbon ratio, CH4 correction factor, oxidation factor and recovery rate, were carefully analyzed in terms of these three dimensions. The point sources database consists of 2,107 MSW landfills in cities and towns of China in 2007. The results show that the CH4 emissions from MSW landfills were 1.186 Mt in 2007. Compared with the CH4 emissions of 2.20 Mt in 2005, the significant discrepancy mainly comes from statistical data of landfills, e.g., number of landfills and amount of waste disposed in landfills. CH4 emissions were lower than 700 t for most of the landfills, whereas there were 279 landfills with emissions larger than 1,000 t, and only 10 landfills with emissions larger than 10,000 t. Jiangsu province ranks the largest emitter with 98,700 t while Tibet is the smallest emitter with 2,100 t. In general, the emissions from eastern provinces, such as Jiangsu, Guangdong and Zhejiang, were larger than those from western provinces, such as Ningxia, Tibet and Qinghai. Citation: Cai, B.-F., Liu, J.-G., Gao, Q.-X., et al., 2014. Estimation of methane emissions from municipal solid waste landfills in China based on point emission sources. Adv. Clim. Change Res. 5(2), doi: 10.3724/SP.J.1248.2014.081.