Municipal Waste Landfill Research Articles

Biopolymer and Gypsum Added Na Bentonite for a More Effective Clay Liner

AbstractBentonite soil is frequently utilized as a compacted clay liner, which is a critical component of municipal waste landfill systems. This study aims to investigate the feasibility of treating sodium bentonite (NAB) with natural biopolymers to obtain an effective clay liner. The NAB was treated with three biopolymers: sodium alginate (SA), agar gum (A), and xanthan gum (X), at different replacement percentages (2%, 4%, 6%, and 8%). Additionally, an investigation was conducted to determine the extent to which replacing 50% of these additives with gypsum (G) would improve the biopolymer treatments. Fourier-transform infrared spectroscopy (FTIR), pH, one-dimensional swelling, and unconfined compressive strength (UCS) were carried out in this study. The FTIR results indicated the presence of intermolecular hydrogen bonding when NAB was treated with biopolymers and gypsum, which is crucial for enhancing the UCS. Furthermore, the thermal treatment of biopolymers significantly contributes to improving the UCS. Among the various biopolymers tested, agar gum demonstrated the most significant improvement, specifically, replacing 8% of the NAB with agar gum resulted in a 55% increase in UCS. Volume change behavior was most influenced by replacement of NAB with gypsum by 8%, which reduced the vertical swelling to 21% as opposed to 79% for the untreated NAB. The use of SA conversely resulted in an increased vertical swelling of 91%.

Long-Term Polyethylene (Bio)Degradation in Landfill: Environmental and Human Health Implications from Comprehensive Analysis.

This study investigates the process of long-term (bio)degradation of polyethylene (PE) in an old municipal waste landfill (MWL) and its implications for environmental and human health. Advanced techniques, such as ICP-ES/MS and IC-LC, were used to analyze heavy metals and anions/cations, demonstrating significant concentration deviations from control samples. The soil's chemical composition revealed numerous hazardous organic compounds, further indicating the migration of additives from PE to the soil. Toxicological assessments, including Phytotoxkit FTM, Microtox® bioassay, and Ostracodtoxkit®, demonstrated phytotoxicity, acute toxicity, and high mortality in living organisms (over 85% for Heterocypris Incongruens). An unusual concentration of contaminants in the MWL's middle layers, linked to Poland's economic changes during the 1980s and 1990s, suggests increased risks of pollutant migration, posing additional environmental and health threats. Moreover, the infiltration capability of microorganisms, including pathogens, into PE structures raises concerns about potential groundwater contamination through the landfill bottom. This research underscores the need for vigilant management and updated strategies to protect the environment and public health, particularly in older landfill sites.

Evaluation of the Activity of a Municipal Waste Landfill Site in the Operational and Non-Operational Sectors Based on Landfill Gas Productivity

This research identifies the productivity of landfill gas actively captured at a municipal waste landfill site with a waste mass exceeding 1 million Mg from sectors in the operational and non-operational phases, considering meteorological conditions. Based on the analysis of landfill gas, including emissions and composition (CH4, CO2, O2, and other gases), the processes occurring demonstrate the impact of the decomposition of deposited waste on the activity of the deposit. With average monthly gas emissions exceeding 960,000 m3, the average content of CH4 (30–63%) and CO2 (18–42%) and the varied content of O2 (0.3–9.8%) in individual sectors of the landfill site were significant. The statistically significant relationship between CH4, CO2, and landfill gas emissions exhibited a noticeable decrease in methane content. Despite the abandonment of waste storage, a high correlation is present between the emission level and methane content (0.59) and carbon dioxide (0.50). In the operational part of the landfill, this relationship is also statistically significant but to a lesser extent; Spearman’s R-value was 0.42 for methane and 0.36 for carbon dioxide. The operational and post-operational phases of the municipal waste landfill demonstrated a noticeable impact from the amount of precipitation, relative humidity, and air temperature, on landfill gas productivity. The generally progressive decline in the activity of the waste deposit, which reflects a decreasing trend in the methane content of approximately 2% annually in the total composition of landfill gas, as well as the share below 50%, indicates the need only to utilise landfill without producing energy.

Employing Plant Parasitic Nematodes as an Indicator for Assessing Advancements in Landfill Remediation

This research concentrated on the soil nematode communities inhabiting a reclaimed municipal waste landfill situated in Giedlarowa, southeastern Poland. The landfill, which was layered with natural soil in 2008 and cultivated with grass, served as the primary focus of the study. Samples for analysis were taken four times (October 2020 (Pf1), March 2021 (Pf2), October 2021 (Pf3), and March 2022 (Pf4)), with each time comprising three repetitions. The analysis was conducted employing microscopic examination, which enabled the identification of up to five trophic groups and species of plant-parasitic nematodes. During the assessment of nematode activity in the initial and subsequent growing seasons, it was found that Pratylenchus crenatus emerged as the predominant species among herbivorous nematodes in the plant-parasitic nematode (PPNs) community. Criconemoides informis, another nematode species, held a significant rank as well; their population during the third growing season formed the most substantial group among the PPN organisms dwelling in the soil. Nevertheless, interesting results were also obtained by populations of nematodes of the genus Hemicyclophora and Loofia, which were characterized by high densities. The analyzed soil environment showcased a C:N ratio spanning from 0.69 to 3.13. Furthermore, the soil samples exhibited variations in phosphorus content (P2O5), ranging from 4.02 mg/100 g to 10.09 mg/100 g. Criconemoides informis, Longidorus attenuates, Mesocriconema spp., and Bitylenchus maximus exhibited a positive correlation with soil mineral levels of calcium (Ca) and magnesium (Mg).

Application of selected groundwater quality indices in anthropogenically transformed areas

Correctly assessing the impact of waste landfills on groundwater quality requires the development and use of comprehensive tools that consider the content of individual components in water, as well as those relating to the hydrochemical background. The article presents a comparative analysis of selected water quality indices used around the world to assess the environmental threat caused by sources of pollution. The paper includes the following indicators: Water Quality Index, Landfill Water Pollution Index, Nemerow Pollution Index, Backman Index, Canadian Water Quality Index, Horizontal Ratio, Enrichment Factor and Fuzzy Water Quality. Attention was paid to the values of individual indices, their applicability in municipal and industrial waste landfills, and limitations in their use. A literature review has proven that some indices, such as the Landfill Water Pollution Index and Nemerow Pollution Index, are used very often as they provide reliable results. Index methods help conduct rational water management, complement groundwater quality monitoring, and serve as a tool for making decisions in various water protection areas.

Thermal Behavior of Ceramic Bodies Based on Fly Ash and Smectites

Clay minerals have a great influence on the resulting properties of ceramic bodies. Fly ash as a waste material from burning black coal in power plants is a potentially valuable source of oxides (Al2O3, SiO2 or Fe2O3) for this production. Considering the process of ceramic firing, it is important to understand the thermal behavior of individual ingredients. The thermal behavior of natural smectite minerals (montmorillonite, beidellite, hectorite and nontronite) and their mixtures with added fly ash at different ratios (10%, 30% and 50%) was investigated. The phase analysis was obtained using X-ray diffraction and FT-IR spectroscopy. Under heating to 1200 °C, the structural changes of smectites were divided into four steps including dehydration, dehydroxylation, decomposition and crystallization of new phases. The addition of fly ash caused a shift in the reaction temperatures for all the mentioned phases. These changes were most noticeable for mixtures with hectorite; on the contrary, they were least noticeable for beidellite mixtures. Total mixture mass loss continually decreased with increasing fly ash amount. The obtained experimental thermal data can be applicable not only in the production of ceramic bodies or energy waste processing but also in construction and ensuring the safety of municipal waste landfills.

Soil processes modify the composition of volatile organic compounds (VOCs) from CO2- and CH4-dominated geogenic and landfill gases: A comprehensive study

Degradation mechanisms affecting non-methane volatile organic compounds (VOCs) during gas uprising from different hypogenic sources to the surface were investigated through extensive sampling surveys in areas encompassing a high enthalpy hydrothermal system associated with active volcanism, a CH4-rich sedimentary basin and a municipal waste landfill. For a comprehensive framework, published data from medium-to-high enthalpy hydrothermal systems were also included. The investigated systems were characterised by peculiar VOC suites that reflected the conditions of the genetic environments in which temperature, contents of organic matter, and gas fugacity had a major role. Differences in VOC patterns between source (gas vents and landfill gas) and soil gases indicated VOC transformations in soil. Processes acting in soil preferentially degraded high-molecular weight alkanes with respect to the low-molecular weight ones. Alkenes and cyclics roughly behaved like alkanes. Thiophenes were degraded to a larger extent with respect to alkylated benzenes, which were more reactive than benzene. Furan appeared less degraded than its alkylated homologues. Dimethylsulfoxide was generally favoured with respect to dimethylsulfide. Limonene and camphene were relatively unstable under aerobic conditions, while α-pinene was recalcitrant. O-bearing organic compounds (i.e., aldehydes, esters, ketones, alcohols, organic acids and phenol) acted as intermediate products of the ongoing VOC degradations in soil. No evidence for the degradation of halogenated compounds and benzothiazole was observed. This study pointed out how soil degradation processes reduce hypogenic VOC emissions and the important role played by physicochemical and biological parameters on the effective VOC attenuation capacity of the soil.

Global perspective of municipal solid waste and landfill leachate: generation, composition, eco-toxicity, and sustainable management strategies.

Globally, more than 2 billion tonnes of municipal solid waste (MSW) are generated each year, with that amount anticipated to reach around 3.5 billion tonnes by 2050. On a worldwide scale, food and green waste contribute the major proportion of MSW, which accounts for 44% of global waste, followed by recycling waste (38%), which includes plastic, glass, cardboard, and paper, and 18% of other materials. Population growth, urbanization, and industrial expansion are the principal drivers of the ever-increasing production of MSW across the world. Among the different practices employed for the management of waste, landfill disposal has been the most popular and easiest method across the world. Waste management practices differ significantly depending on the income level. In high-income nations, only 2% of waste is dumped, whereas in low-income nations, approximately 93% of waste is burned or dumped. However, the unscientific disposal of waste in landfills causes the generation of gases, heat, and leachate and results in a variety of ecotoxicological problems, including global warming, water pollution, fire hazards, and health effects that are hazardous to both the environment and public health. Therefore, sustainable management of MSW and landfill leachate is critical, necessitating the use of more advanced techniques to lessen waste production and maximize recycling to assure environmental sustainability. The present review provides an updated overview of the global perspective of municipal waste generation, composition, landfill heat and leachate formation, and ecotoxicological effects, and also discusses integrated-waste management approaches for the sustainable management of municipal waste and landfill leachate.

Risk analysis for groundwater in the area of the municipal waste landfill in Sosnowiec, South Poland

Abstract Risk assessment for groundwater allows for preventive activities in the field of environmental monitoring. The risk assessment for groundwater in the area of the municipal waste landfill in Sosnowiec was carried out using the Nemerov Index (NPI) and the Enrichment Index (EF), as well as a SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis and a risk matrix. It was performed on the basis of the database from 2014-2019 for ten piezometers belonging to the landfill’s observation network. In the case of the risk matrix, 20 risks were identified regarding climatic conditions, landfill infrastructure and employees. The SWOT analysis considered the strengths and weaknesses of the facility as well as opportunities related to technological development and threats related primarily to the location of the facility within the landscape. The risk assessment indices were calculated for the following parameters: electrolytic conductivity, Na, Mg, K, Ca, Mn, Fe, TOC, HCO3, Cl, SO4, and NH4. The highest values of the NPI index exceeded 3,500 (in a single measurement), while for the EF index the values reached almost 500. These prove the impact of this facility on the quality of groundwater. However, hydrochemical background value and the value of the immobile parameter are also important. This article uses limit values for the first class of groundwater quality. The results of above mentioned methods indicate a medium risk to groundwater, and the opportunities and strengths of the facility outweigh the negative aspects of the plant’s operation. Further research should include the identification of additional risk factors and the likely response to risk.

Growth, Hematological Evaluation and Heavy Metal Bioaccumulation in Nile Tilapia (Oreochromis niloticus) from A Municipal Waste Landfill Reservoir

The aim of this study was to evaluate the growth performance, mortality rate, and blood profile of Cd-, Pb-and Cr-contaminated Nile tilapia from the Khon Kaen municipal waste landfill reservoir and compare the parameters with those of fish from unpolluted sites. Human bioaccumulation factor (BAF) determination was also performed. Thirty samples of Nile tilapia were taken from the Khon Kaen municipal waste landfill reservoir (CN) and from unpolluted (TN) ponds. Water and soil were collected from these sites, and tilapia muscle, gill, and liver were obtained for heavy metal evaluation. The Cd concentrations in the muscle, gill and liver were 0.003 ± 0.001, 0.006 ± 0.008, and 0.004 ± 0.003 mg/kg; the Pb concentrations were 0.078 ± 0.173, 0.880 ± 1.360 and 1.110 ± 1.862 mg/kg; and the Cr concentrations were 0.067 ± 0.135, 0.572 ± 1.098 and 0.636 ± 1.272 mg/kg, respectively. The total fish length, body weight and survival rate were significantly lower in the TN group (P <0.05), and alanine aminotransferase and creatinine were significantly (P <0.05) higher in the TN group. The hematocrit count of the TN group was also lower than that of the CN group but without a significant difference. The BAF ranged from 0.1-4.3, especially in the gills and liver, which are major heavy metal accumulation organs. Heavy metal contamination in landfill leachate negatively affects fish health and its production. Keywords: Aquaculture, Nile tilapia, Heavy metal, Pathology, Toxicity

Assessment of the influence of the toxic effect of municipal solid waste on the ecological state of the soil

Introduction. Тhe municipal solid waste of pollution negatively affects on the state of the environment, since during their storage on the territory of landfills and the adjacent territory, accumulation of heavy metals (HM) can change the biological indicators of soil conditions: microbiological, biochemical, and phytotoxic.
 The aim of the study was to assess the influence of the toxic effect of the municipal waste landfill “Azov” in the Rostov region on the ecological state of the soil. 
 Materials and methods. It was explored the influence of municipal solid waste landfill “Azov” of the Rostov region on the ecological condition of the ordinary chernozem in the landfill and adjacent territory (140, 260, 380, and 540 m). The content of heavy metals in the soil, such as chromium (Cr), strontium (Sr), zinc (Zn), vanadium (V), copper (Cu), nickel (Ni), cobalt (Co), lead (Pb), and arsenic (As) were defined. The ecological state is assessed by sensitive and informative-biological indicators of soil pollution: the abundance of bacteria of the genus Azotobacter, the total prevalence of soil bacteria, the activity of catalase, dehydrogenases. 
 Results. Soils were found to contaminate with arsenic by MAC / TAC (exceeding the MAC by 7 times at the landfill and exceeding the MAC by 4 to 6 times in the territory). Pollution with heavy metals according to German MACs with chromium exceeded by 1.4 times). The highest concentration of heavy metals prevailed in the body of the landfill. Depending on distance from the landfill the concentration of heavy metals in the soil decreased. HM contamination leads to negative consequences for the ecological state of ordinary chernozem: the total number of bacteria decreases (until to 95% of the control), the number of the genus Azotobacter decreases (up to 95% of the control), the activity of catalase (up to 25% of the control) and dehydrogenase decreases (up to 30% of control) and increased soil phytotoxicity (up to 60% of control). It can be concluded that the exploitation of the landfill leads to a deterioration of the environmental situation on the territory of the landfill and beyond.
 Limitations. The ecotoxic effect of HMs on soils less buffered to pollution will be higher than on the chernozems studied in the article.
 Conclusion. The Landfill “Azov” was found to impact on the microbiological, biochemical, and phytotoxic parameters of the soil negatively. This problem connects with influence of heavy metals which get into the soil of during the operation of the landfill. The most sensitive and informative biological indicators are total number of bacteria and length of radish roots.

Determination of the sanitary protection zone of municipal waste landfill based on evaluation of the environmental hazards: Case study of the Zhytomyr territorial community, Ukraine

Today, Ukraine is far from European standards, and the country's waste management system remains confronted with environmental and technogenic problems, with 7 % of the territory occupied by landfills. Most settlements in Ukraine do not have solid waste management programs or sanitation schemes. Landfills, and especially municipal solid waste dumps, are significant contributors to air, water, and soil pollution. The objective of this research is to develop a comprehensive understanding of the environmental impact of landfills, to translate them from a descriptive and abstract plane to a mathematical plane, and to identify the sanitary protection zones currently utilized for landfills. The subject of this study is the municipal waste landfill of the Zhytomyr territorial community (Ukraine), a typical Ukrainian landfill operated with minimal environmental protection measures.The authors used an original approach to assess the environmental hazard of a municipal waste landfill, taking into consideration the values of absolute indicators of water pollution for specific physicochemical characteristics; maximum permissible concentrations of the studied indicators; distance from the landfill boundary; the amount of excess of the absolute indicator of pollution compared to the MPC; and the intensity of odor in the landfill. The calculated pollution indicators served as the basis for an integrated assessment of the environmental hazards posed by the municipal waste landfill.The study revealed that the Ot indicator (evaluation of the environmental hazards of municipal waste landfills) depends exponentially on the landfill boundary. Based on the value of Ot, environmental zoning was carried out: according to the calculations and taking into account the monitoring of the environmental condition in the landfill's impact zone, the authors recommended the parameters of environmental zoning on the basis of the Ot value.The purpose of this study is to clarify the sanitary protection zones that are currently used for landfills and solid household waste disposals.The research materials can also be used to create databases on landfills, enabling the development of a plan to manage them as sources of heightened environmental risk.

Optimal layout design of groundwater pollution monitoring network using parameter iterative updating strategy-based ant colony optimization algorithm.

The scientific layout design of the groundwater pollution monitoring network (GPMN) can provide high quality groundwater monitoring data, which is essential for the timely detection and remediation of groundwater pollution. The simulation optimization approach was effective in obtaining the optimal design of the GPMN. The ant colony optimization (ACO) algorithm is an effective method for solving optimization models. However, the parameters used in the conventional ACO algorithm are empirically adopted with fixed values, which may affect the global searchability and convergence speed. Therefore, a parameter-iterative updating strategy-based ant colony optimization (PIUSACO) algorithm was proposed to solve this problem. For the GPMN optimal design problem, a simulation-optimization framework using PIUSACO algorithm was applied in a municipal waste landfill in BaiCheng city in China. Moreover, to reduce the computational load of the design process while considering the uncertainty of aquifer parameters and pollution sources, a genetic algorithm-support vector regression (GA-SVR) method was proposed to develop the surrogate model for the numerical model. The results showed that the layout scheme obtained using the PIUSACO algorithm had a significantly higher detection rate than ACO algorithm and random layout schemes, indicating that the designed layout scheme based on the PIUSACO algorithm can detect the groundwater pollution occurrence timely. The comparison of the iteration processes of the PIUSACO and conventional ACO algorithms shows that the global searching ability is improved and the convergence speed is accelerated significantly using the iteration updating strategy of crucial parameters. This study demonstrates the feasibility of the PIUSACO algorithm for the optimal layout design of the GPMN for the timely detection of groundwater pollution.

Environmental impacts of 5-year plastic waste deposition on municipal waste landfills: A follow-up study

Depositing plastic waste has long been a prevalent method of utilization, persisting today. Plastic waste within municipal waste landfills (MWL) undergoes diverse (bio-)degradation processes, which may be a potential source of chemicals and microorganisms harmful to the environment and human health. Soil and air samples were collected from modern MWL to identify environmental contamination caused by 5 years of plastic (bio-)degradation. The pH of soil samples was higher than in the reference area (RA), which was possibly caused by alterations in soil anionic composition detected with ion chromatography. The presence of plastic additives with a toxic potential was detected in soil samples by gas chromatography coupled with tandem mass spectrometry (GC–MS/MS). With the use of thermal desorption and GC – MS, hazardous substances (phthalic anhydride, phenylmaleic anhydride, ethylbenzene, xylene) with a known impact on the human endocrine system were also detected. The number of microorganisms, both fungi, and bacteria, was highly increased in soil and air in the MWL as compared to the RA. The soil collected in the MWL area appeared to be phytotoxic, and inhibited seed germination (Phytotoxkit FTM bioassay), while acute toxicity Microtox® bioassay showed a hormetic effect towards Aliivibrio fischeri. Obtained results exhibited massive soil and air contamination, with both chemical substances and microorganisms while plastic waste undergoes (bio-)degradation. It may contribute to serious environmental contamination and pose a threat to human health.

Evaluation of combined thermo-chemical processes for the treatment of landfill leachate using virgin and recovered FeCl3 coagulants

Sludge resulting from treatment of municipal waste landfill leachate contains suitable cationic substances such as Fe-based recovered coagulants which, if not recovered, can cause environmental problems. The present study aimed to maximise coagulant recoverability and investigate its potential reuse for the treatment of municipal waste landfill leachate. The study focused on establishing (i) the effect of mineral acids on leaching of Fe, (ii) the % of maximum recovery of Fe coagulant, (iii) the impact of ultrasound on recovery, and (iv) effectiveness of recovered coagulant when reused in coagulation-flocculation treatment of landfill leachate. Sulfuric acid outran hydrochloric acid in performance, with the acid leaching process leading to the recovery of 70.12% of Fe (acid concentration = 3.80 M, solid-to-liquid ratio = 8%, and heating time = 5 h). Subsequently, a developed acid leaching process was tested, which results showed that the highest rate of Fe recovery occurred without ultrasound treatment, meaning the use of it could reduce the recovery rate due to the increase in the iron (III) oxide-hydroxide [Fe(OH)3] sedimentation. Comparative experiments were undertaken with the recovered and virgin coagulants. These revealed that Fe-based recovered coagulant led to the 60.21% and 91.40% removal of COD and total suspended solid respectively, while the values of the COD and total suspended solid removal with the virgin FeCl3 were 7.66% and 6.42% lower than that of Fe under optimal conditions (dosage = 9.38 g/L, pH = 8.94, settling time = 52.9 min). The present study established that Fe recovered could be exploited as an eco-friendly coagulant to replace FeCl3 in the landfill leachate treatment.

Municipal waste management in municipalities in Poland – towards a circular economy model

The aim of the study was to answer the question of to what extent it is possible in Poland to reach the target recycling rates and landfill of municipal waste by 2035 and build a circular economy model (CEM) by 2050. The authors will continue research in this area. In the article, the authors: 1) diagnose EU and Polish legislation in the given area, 2) review the literature with regard to the circular economy, 3) analyse municipal waste streams in Poland and present their forecasts for the period of Poland’s approach to the CEM. The data were taken from the public statistics and refer mainly to the period 2013-2021. The study used the method of literature analysis and legal regulations, as well as methods of descriptive analysis and linear extrapolation. The results obtained, albeit aggregated, suggest that it is possible to reach the EU-targeted recycling and landfill level for municipal waste in Poland by 2035 and the CEM by 2050.

The impact of weather conditions on the quality of groundwater in the area of a municipal waste landfill

Abstract The quality of groundwater in the source area of pollution depends on many factors, including the weather and hydrogeological conditions within the given area. Anassessment of water quality can be carried out based on data obtained from sensors placed in boreholes. This research examined the influence of air and water temperature, groundwater table position and precipitation on the value of electrical conductivity in groundwater in a selected piezometer belonging to the monitoring network of the Quaternary aquifer in the area of a waste landfill site in Tychy-Urbanowice in southern Poland. The influence of individual factors was checked by using twenty neural network architectures of a Multilayer Perceptron Model (MLP). Each of these indicated factors were selected as input variables. Ultimately, three neural networks were selected, which were characterized by the smallest validation and test errors and showed the highest learning quality. The significance of individual variables for the effectiveness of the model was checked using a global sensitivity analysis. Three selected MLP models contained seven to nine neurons in the hidden layer and used a linear or exponential function as the hidden and output activation. The maximum test quality was 0.8369, while the smallest test error was 0.0011. The results of the sensitivity analysis highlighted the important role of water temperature and water table position on the conductivity value. The obtained goodness of fit results of the models to the input data allowed us to conclude that the MLP was applicable to such forecasts and can be extended by the analysis of further factors.

DURABILITY TESTS OF GEOSYNTHETIC MATERIALS USED IN DIFFICULT ENVIRONMENTAL CONDITIONS

The article describes the ageing process of high-density polyethylene (HDPE) geogrids under the influence of chemical and environmental factors. Research on accelerated ageing of a uniaxial HDPE geogrid incubated in a water solution for a period of 12 months is presented. Three temperatures (25°, 45° and 75°C) were selected for the accelerated ageing tests in aqueous solutions simulating the conditions at a municipal waste landfill. Changes were observed using differential scanning calorimetry (DSC), and correlations with the mechanical properties of the aged geogrid were checked. No significant effect of the loss of antioxidant in the material on the mechanical properties of the uniaxial geogrid was observed. The tests made it possible to determine the mechanical properties, such as tensile strength and deformability of the geogrid – which are extremely important in the analysis of slope stability.

Indoor air quality assessment on polygons for solid municipal waste for microbial contamination and a method of its cleaning

Landfill biogas contains large amounts of toxic and harmful impurities and may be a source of microbiological contamination of both the complex municipal waste landfill itself and adjacent territories. This paper uses modern biotechnologies designed to protect the environment, to study the quantitative and qualitative composition of biogas for harmful factors, as well as for harmful substance removal from biogas. An assessment was made of air purification in the premises near landfills and adjacent territories using green plantations and a biological system based on an apparatus-biological complex for purification from microbiological contamination. The data obtained in our laboratory studies show that such apparatus-biological complexes can reduce the negative influence on the personnel and workers at operative points and the inhabitants of adjacent territories by air purification.

Application of a geographic information system and the method of analysis of hierarchies to assess construction sites for landfills for municipal waste in the Khabarovsk Territory

An integrated system for managing municipal solid waste at the regional level should be consistent with the goals of Russia's sustainable development. The key element of the system is the landfill. One of the most pressing issues in waste management is the choice of a suitable site for the construction of a landfill. This article presents the results of a study on the use of a geographic information system and the method of analyzing hierarchies to select a land plot for a municipal waste disposal site in the Komsomolsk cluster of the Khabarovsk Territory. Three land plots proposed by the municipal authorities for the construction of the landfill were studied using eleven evaluation factors. Evaluation factors were the population within a radius of 1.5 km, the presence of enterprises within a radius of 1.5 km, the population density in the service area, the distance to the boundaries of the settlement, the distance to the airport, the distance to water bodies, the current use of the land, the depth of the first aquifer, site slope, site area, distance to transport routes. As a result of the study, it was shown that the option of locating the MSW landfill in the Solnechny municipal district is the most preferable in terms of a set of evaluation factors. The worst option is the construction of a landfill in the vicinity of Komsomolsk-on-Amur. The study showed that solving the problem of taking into account socio-economic and sanitary-environmental factors when choosing a land plot for the construction of a MSW landfill requires a practical methodology that can reduce the subjectivity of a management decision. Satisfying the need for a methodology to improve the validity of management decisions when choosing the best places for the construction of MSW landfills is possible through the use of GIS technologies and a multi-criteria decision support system.