Leachate Parameters Research Articles

Assessment of leachate potential contamination of municipal landfill using leachate pollution index and multivariate statistical analysis based on seasonal variations

Sanitary landfills offer a convenient and cost-effective way to dispose of MSW waste. The breakdown of waste in landfills generates highly poisonous leachate. This liquid can disperse and percolate through the soil, potentially polluting the surrounding water bodies; minimizing the environmental damage caused by leachate lies in thoroughly understanding its unique characteristics at each landfill site. The present study evaluates the leachate's physio-chemical characteristics from municipal landfills and adjacent groundwater sources. To evaluate the impact of temporal seasonal fluctuation, leachate and water samples were collected in three distinct seasons such as pre-monsoon (Pre-M), monsoon (In-M), and post-monsoon (Post-M). The analysis revealed a seasonal variation in pollution levels in the leachate sample, as evidenced by the high Leachate Pollution Index (LPI) spanning 27.121–17.396. Water samples collected across three seasons yielded Water Quality Index (WQI) values ranging from 55.59 to 279.64, with the Pre-M season exhibiting the highest level of water quality. Scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis were employed to understand the elemental composition further. The presence of heavy metals Zn, Cr, Cu, Ni, Fe, Si, and Hg was determined combined through the Inductive Coupled Plasma Atomic Emission Spectroscopy technique and EDX. The correlation matrix heat map helped to reveal the interconnection between different leachate parameters, and dendrogram clusters revealed the relation between the six sampling points. At the same time, Principal component analysis was performed to simplify the complex data set and determine the predominance of pollutants over the sample points. As explored in this study, understanding the contamination potential of landfill leachate is crucial for developing strategies before its disposal to mitigate its impact.

Exploring relationships among landfill leachate parameters through multivariate analysis for monitoring purposes.

Elucidating the properties of landfill leachate and the relationships among leachate parameters is crucial for efforts to determine appropriate landfill leachate monitoring activity and management strategies. This study investigated the physical, chemical and optical parameters of leachate in an old Japanese landfill over a 13-month period. The parameters were explored based on their relationships with the maximum fluorescence (Fmax) of three components (microbial humic-like C1, terrestrial humic-like C2 and protein-like C3) deconvoluted from excitation-emission matrix fluorescence spectroscopy coupled with parallel factor analysis. Dissolved organic carbon (DOC), chemical oxygen demand (COD), Cl- and SO42- concentrations and pH ranged from 2.6 to 38.2 mg C L-1, 9 to 324 mg L-1, 14 to 972 mg L-1, 26 to 1554 mg L-1 and 6.9 to 11.6, respectively. Linear regression analysis suggested that the Fmax values of C2 and C3 represented DOC, whereas the Fmax value of C2 alone could serve as a COD indicator. Hierarchical cluster analysis and principal component analysis were employed to successfully categorise leachate samples based on their locations. Higher dissolved organic matter levels were observed in leachate within the old disposal area, whereas elevated levels of inorganic components such as SO42- and Cl- were found in leachate collected from the extended disposal area and at a treatment facility. Statistical analysis provides crucial tools for assessing and managing various areas of a landfill, supporting targeted and effective waste management strategies.

Dynamic interaction of heavy metals and mineralogical shifts in stream sediments exposed to MSW landfill leachate in a semi-arid basaltic terrain

Investigating concentrations and spatial patterns of physicochemical parameters in landfill leachate and their profound impacts on stream sediments is an important issue for environmental sustainability. Therefore, the present study showed that the specifics landfill leachate and its interactions with stream sediments within the unique geological context of semi-arid basaltic terrain of the Deccan Volcanic Province in Pune, India. Employing advanced geo-accumulation indices and crystal phase differentiation methods, the study unveils the intricate metamorphosis of heavy metals and mineralogical composition, tracing the transformative journey from leachate to sediments. Noteworthy revelations emerge, particularly in the striking associations between heavy metals and the mineralogical composition, which encompasses primary and secondary minerals (calcite, quartz, and Fe–Mg oxides). These findings underscore the acceleration of weathering processes within this distinctive geological milieu. The 'geo-accumulation index' exhibits pronounced elevations in proximity to the landfill site, with persistence downstream, reliant upon the evolving weathering and accumulation dynamics. The lower reaches of the study area have higher concentrations of various heavy metals (Fe, Mn, Zn, Cr, Cu, Ni, Co, Hg, As, and Cd). These heavy metals are primarily sequestered within silt-dominated sediments conquered by augite, olivine and plagioclase minerals. Present research reveals the complex interplay between heavy metals in leachate and their physical and chemical interactions with sedimentary materials. These gradational shifts in mineralogy and geochemistry serve as compelling evidence of the transformative impact of leachate discharge within the distinctive basaltic geological framework. This study offers valuable insights into the complex environmental processes occurring at the intersection of landfill leachate and natural geological formations, enhancing the understanding of the dynamic geochemical interactions that shape this semi-arid basaltic terrain.

Statistical investigation of climate and landfill age impacts on Kupferberg landfill leachate composition: one-way ANOVA analysis

This study investigated seasonal variations in the physico-chemical properties of leachate from the Kupferberg landfill site, examining the influence of landfill age and climatic factors. Data provided by the Windhoek Municipality during the years 2017 to 2022 facilitated the exploration of critical concerns related to groundwater protection and human health. Guided by two research questions and anchored in hypotheses tested at a 95% confidence level, the study employed Statistical Packages for Social Scientists (SPSS) for analysis.Significant temperature variations were observed across years [F (5, 21) = 4.493, p < 0.05], indicating a substantial relationship between landfill age and seasonal variations in leachate physico-chemical properties. Further ANOVA tests revealed temperature trends impacting leachate parameters, such as organic content and pH. While COD displayed a declining trend with landfill age, inorganic components like Cl- and alkalinity exhibited no distinct age-related pattern.Wet seasons demonstrated higher EC and Cl--mean values than dry seasons, correlating with elevated COD levels. The study underscored the incremental rise in parameter values over time and during the rainy season, attributed to solid waste degradation and rainwater percolation. Notably, climatic conditions significantly influenced seasonal variations in leachate physico-chemical properties (p < 0.05). Based on this outcome, null hypothesis 1 was rejected. The second null hypothesis was also rejected because climatic conditions do influence the seasonal variations in physico-chemical properties. These findings are crucial for emphasizing the need for effective leachate management strategies and providing valuable insights for arid regions. Future research can expand on a national scale, employing one-way ANOVA tests on other landfills in Namibia, and engaging local communities for comprehensive data collection on cross-contamination.

Deteksi Konsentrasi Fe, Cu, Zn dan Pb Air Sungai dan Ikan yang Tercemar Air Lindi di Bandar Lampung Dengan Menggunakan SSA

Leachate is a pollutant produced by landfills which can pollute the aquatic environment. This will have an impact on fish that live in waters contaminated with leachate and if consumed by the public it will harm health. The toxic effects of leachate are caused by the content of toxic chemicals, one of which is heavy metals. The aim of this research was to determine the concentrations of Fe, Cu, Zn and Pb in Bakung landfill leachate, Sukamaju river water and fish meat. Bakung landfill leachate samples were taken from two outlet points. The fish sampling location was carried out in the Sukamaju River. The physical factors of water measured are temperature, pH, salinity, turbidity, DO, COD and BOD. Fe, Cu, Zn and Pb concentrations were measured using the Atomic Absorption Spectrophotometry (AAS) method. The results show that the physicochemical parameters in leachate and river water exceed the threshold. The contents of Zn, Cu, Fe and Pb in the leachate at both outlet points exceeded the threshold value with values of 2.48 mg/L and 2.80 mg/L; 16.55 mg/L and 17 mg/L; 0.078 mg/L and 0.113 mg/L; 3.26 mg/L and 3.01 mg/L. The concentration of heavy metals Pb and Fe in river water is 0.083-0.162 mg/L and 2.68-2.97 mg/L which are above the quality standard value, while the heavy metal Fe content in fish meat exceeds the specified threshold value, namely 0.557 mg/100 g and 0.564 mg/100 g.

Analysing the factors influencing groundwater quality with different pollution indices and PLS-SEM approach in the vicinity of an open dumping yard in Saduperi, Vellore, Tamil Nadu, India.

Open dumping is the prevailing municipal solid waste (MSW) disposal technique in India. Unsanitary landfill releases leachate that contaminates valuable groundwater. Hence, the present study was carried out in the vicinity of the Saduperi open dumpsite, Vellore, Tamil Nadu, India, to explore the key factors that influences groundwater contamination. A total of 216 groundwater samples were collected between May 2021 and April 2022. These samples were categorised into four different seasons such as summer, southwest monsoon (SWM), northeast monsoon (NEM), and winter. Pollution indices such as the Leachate Pollution Index (LPI) and the Heavy Metal Pollution Index (HPI) were used to evaluate the contamination potential. The calculated LPI > 35 in all seasons indicates the prevailing poor environmental condition. It was observed that about 56% of the sampling site was affected by heavy metal concentrations such as Cd, Cr, and Ni. The HPI value was found to be more than the critical value of 100 in the 10 sampling wells for all seasons. Partial least squares-structural equation modelling (PLS-SEM) has also been carried out in this study to create a link between latent variables such as 'IOT Parameters', 'Leachate Parameters', 'Heavy Metal', and 'Groundwater Quality' which were quantified by the yield of R2 value. The R2 value of the sampling well ahead of the dumpsite and along the direction of the groundwater flow values ranges from 24.7 to 86.5% in comparison to the wells located behind the dumpsite, which are prone to more contamination due to migration of leachate. Hence, this present study shows various influencing factors that affect the groundwater quality.

Pengolahan Lindi Tempat Pemprosesan Akhir Sampah Talang Gulo Dengan Metode Elektrolisis

The Talang Gulo control landfill waste final processing site (TPA) has been decommissioned and converted into a Sanitary Landfill TPA in the city of Jambi. Even though it has been deactivated, the waste resulting from the decomposition of waste at the TPA control landfill must be managed. One of the wastes that is managed is leachate. Before being released into the environment, leachate must be processed in leachate ponds so that the receiving environment is not polluted. Some of the leachate parameters that must be managed are mercury (Hg) and cadmium (Cd), because if these two parameters enter surface water they will have a negative impact on aquatic biota. The research is planned at the Batanghari University Engineering Laboratory. On a laboratory scale, the Hg and Cd parameters of leachate can be reduced using the electrolysis method. Electrolysis is an alternative method for processing leachate because the chemical reaction process using electrodes can reduce the Hg and Cd parameters. The hypothesis that can be taken is that the electrolysis method can reduce the Hg and Cd parameters of landfill leachate.

INFLUENCE OF PARTICLE SIZE DISTRIBUTION OF HAZARDOUS SOLID WASTE INCINERATION ASHES (HSWIA) ON LANDFILL LEACHATE FILTRATION

The study examines the reuse of hazardous waste incineration ashes in landfill leachate treatment. Its objective is to assess how the particle size distribution of the ashes affects the reduction of physicochemical parameters in leachate at the Caucaia Sanitary Landfill in Ceará, Brazil, thus valorizing them and minimizing their disposal in landfills. Two filtration columns with ashes of different particle sizes (F1 sieved and F2 raw) were set up. Leachate collected from the landfill was analyzed before and after filtration, demonstrating effectiveness in removing parameters such as phosphorus, nitrite, turbidity, nitrate, etc. The characterization of the ashes revealed differences between the samples, including varying levels of oxides and particle sizes. Results suggest potential use in pre-treatment to reduce pollutant loads before the primary treatment of leachate. The study underscores the potential of incineration ashes to enhance leachate treatment and reduce the environmental impact of improper disposal.

Analysis of the Performance of Cover Soil in Attenuating the Physicochemical Parameters of Landfill Leachate by Soil Column Test

Landfill leachate is of environmental concern due to its high levels of organic and inorganic pollutants. Leachate treatment using natural materials such as cover soil of sandy loam texture, laterites, and compost was performed through soil column experiment. This study aims to analyze the natural attenuation of physiochemical parameters such as pH, turbidity, electrical conductivity, biological oxygen demand, chemical oxygen demand (COD), ammonia, phosphate, heavy metals (Fe, Ni, and Pb) of leachate in the cover soil of the Sisdole landfill site (SLS) and enhanced cover soil, that is, a mixture of SLS soil, compost, and laterite (SCL). In addition, this study analyzes the response of the cover soil after infiltration of leachate in terms of physiochemical parameters. Two columns of specific heights and diameters were taken and leachate was fed manually into the soil columns to evaluate the attenuation of the physiochemical parameters of leachate by standard methods after passing through SLS and SCL soil. From the results, it was observed that the removal efficiency was the highest for the first three days (>70%), after which the capacity of the soil to attenuate leachate parameters decreased. Consistent and greater removal efficiency was seen for heavy metals and phosphate for the SLS soil column. Amendments such as laterite and compost were added to cover soil to enhance the performance of SLS soil. The results showed a consistent and greater removal percentage for COD and ammonia in SCL than in SLS soil column. It was observed that that studied soil (sandy loam) is capable of removing pollutants from leachate to a satisfactory level and adding materials with higher sorption capacity such as laterite and compost to sandy loam soil can improve removal ability for certain selected parameters.

The Effect of Eco-Enzyme Spraying on Suwung Landfill Waste, Denpasar, on Changes in Leachate Characteristics

Introduction: Bali, as an international tourist destination, is still experiencing problems in waste management. Suwung Landfill, Denpasar, is one of the landfills for waste originating from the Denpasar, Badung, Gianyar, and Tabanan (Sarbagita) areas. Methods: This research was an experimental study, by watering eco-enzymes on garbage heaps and examining changes in leachate parameters. Watering was carried out daily at a dose of 1 L of eco-enzyme dissolved in 1000 L of water and used for watering a garbage pile of 1 ha. The area of piles of garbage watered with eco-enzymes reaches 5 ha. Measured leachate parameters include pH, BOD, COD, TSS, N, cadmium, and mercury. Results and Discussion: Eco-enzymes have the potential to become activators or decomposers in waste composting. The evidence is that eco-enzyme watering causes the average leachate temperature to range from 36.63 to 40.370C, where the increase in leachate temperature occurs due to the rise in the temperature of the garbage pile. An increase in temperature characterizes the activity of microbes increases, so the decomposition process becomes rapid. Conclusion: Eco-enzyme spraying leads to a characteristic change in the form of an increase in the value of leachate parameters. The increase in temperature value, pH, BOD, COD, and N content of leachate indicates that environmentally friendly enzymes accelerate the decomposition of organic matter. The rapid decomposition process causes the total suspended density of leachate to increase.

Characteristics and pollution potential of leachate from municipal solid waste landfills: Practical examples from Poland and the Czech Republic and a comprehensive evaluation in a global context

The formation of leachate is mainly due to the percolating of rainwater through the body of the landfill and the physical, chemical, and biological processes taking place inside the body of the landfill. The characteristics and pollution potential of leachate from the municipal solid waste (MSW) landfills in Poland (Łubna) and the Czech Republic (Zdounky) is presented. The objectives of this study are: 1) to evaluate and compare physicochemical characteristics of leachate, 2) to demonstrate the variability of leachate parameters in time, concerning stabilization phase of the landfill, 3) to present existing relationships between the characteristics of the leachate, 4) to indicate the factors determining the variability of the leachate composition. The Leachate Pollution Index (LPI) was applied to indicate temporal changes in leachate pollution, to assess polluting ability of leachate, and to compare the pollution potential of leachate. For the Łubna landfill, the minimum, maximum, and average values of LPI were: 6.10, 39.41, and 18.44, respectively. The LPI for the Łubna landfill tends to decrease in time due to stabilization of wastes. For the Zdounky landfill, temporal decreasing of LPI was not observed. The minimum, maximum, and average values of LPI were: 6.25, 14.25, and 10.11, respectively. Alkaline characteristics of leachate from both landfills indicate the mature stage of waste storage. This phenomenon was also evidenced by the Chemical Oxygen Demand (COD), ammonium (NH4+), and cadmium (Cd). For both landfills, pH was negatively correlated with most of the leachate parameters. It is the task for environmental engineers to confront existing knowledge (supplemented by the results of this work) about the properties of leachate, its changes over time and its polluting potential with the possibilities of treating and managing it properly.

Analysis of Leachate from the Municipal Solid Waste Disposal Site and Its Impact on Ground Water Quality At, Lucknow Cantonment

Abstract: Open dumping of municipal solid waste is prone to groundwater contamination because of leachate production. In this report, an attempt has been made to assess the pollution potential of leachate generated from the solid waste disposal site and its impact on aquifers in Neil line Lucknow environs, Uttar Pradesh, India. Physico-chemical parameters of leachate are determined to evaluate water quality index (WQI) .A large amount of the water requirement of Lucknow City is supplied from groundwater. The quality of this groundwater was determined by taking samples from wells within the study area. The purposes of this investigation were .To provide an overview of present groundwater quality . To determine spatial distribution of groundwater quality parameters such as pH, electrical conductivity, Cl− , SO4 −2 , hardness, and NO3− concentrations, and.To map groundwater quality in the study area by using GIS and Geostatistics techniques. ArcGIS 9.0 and ArcGIS Geostatistical Analyst is used for generation of various thematic maps and ArcGIS Spatial analyst to produce the final groundwater quality map .

Analysis of Leachate from the Municipal Solid Waste Disposal Site and Its Impact on Ground Water Quality at Lucknow Cantonment

Abstract: Open dumping of municipal solid waste is prone to groundwater contamination because of leachate production. In this report, an attempt has been made to assess the pollution potential of leachate generated from the solid waste disposal site and its impact on aquifers in Neil line Lucknow environs, Uttar Pradesh, India. Physico-chemical parameters of leachate are determined to evaluate leachate pollution index (LPI) .A large amount of the water requirement of Lucknow City is supplied from groundwater. The quality of this groundwater was determined by taking samples from wells within the study area. The purposes of this investigation were to provide an overview of present groundwater quality. To determine spatial distribution of groundwater quality parameters such as pH, electrical conductivity, Cl− , SO4 −2 , hardness, and NO3− concentrations, and To map groundwater quality in the study area by using GIS and Geostatistics techniques. ArcGIS 9.0 and ArcGIS Geostatistical Analyst is used for generation of various thematic maps and ArcGIS Spatial analyst to produce the final groundwater quality map .

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

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

Environmental Risk Analysis of Final Processing Sites (TPA) Using the Integrated Risk Based Approach (IRBA) Method: A Case Study of TPA with Landfill Control System

The place processing end (TPA) Ussu is located in Ussu village, Malili, East Luwu district, South Sulawesi Province. It has been operated since 2015 with a 4 ha land area and serves 5 districts, namely Malili, Angkona, Wasuponda, Towuti, and Noah. In 2019, this landfill was diverted into a system control landfill, but the implementation is still a conventional use system of open dumping. The system has a high risk for the environment, such as water pollution, soil consequence leachate, air pollution that is caused by methane gas, the emergence of disease, and the risk of landfill fire. Risk analysis is required to describe the risk toward the environment from certain activities. The study is conducted to evaluate the risk to the environment from the operational place processing end (TPA) in Ussu. The research method used is the integrated risk-based approach (IRBA) method. The experimental parameters are in the form of 20 TPA criteria parameters, four characteristics of landfill waste, and leachate parameters. Research results show that TPA Ussu scored 477.54 in the category evaluation danger ' medium ' level. The indicator has shown there are risks toward the environment at a medium level. This caused the landfill's age to be still young and hence required rehabilitation based on conditions in the field with repair system operational landfill control by gradually reducing or lowering danger risk environment.

Temporal study of physicochemical parameters of leachates and assessment of solid waste and ground water quality of Pirana dumping site, Ahmedabad, India.

The characterisation of solid waste (SW), leachate, is essential for developing an appropriate management strategy or treatment method. However, due to a range of contributing factors, such as waste type and dumping site locations, forecasting leachate quality is often challenging. This research article discusses leachate quality indicators and the temporal variations of leachate quality collected throughout various seasons and after 1-2years of storage. In addition to that, the article also provides the data of different physicochemical parameters of SW and ground water (GW) quality collected from of Pirana solid waste dumping area (Pirana SWD), Ahmedabad, India, and surrounding areas throughout various seasons. The parameters like pH, COD, TDS, sulphates, nitrates, ammonia nitrogen, hardness, and heavy metals were all monitored to see whether there any temporal variations. When leachates were obtained 'fresh,' all parameters evaluated showed significantly higher values. As time passed, the values of the parameters (COD, ammonia nitrogen) stabilised. Heavy metals such as Hg, As, Pb, and Cr were detected in both fresh and old samples. Similarly in SW, the presence of heavy metals Hg (0.39ppb), Pb (1.12ppb), and Cr (16.86ppb) were also detected. In case of GW, some samples also show the high TDS but the presence of metals like Cr, Ni, and Zn is less than permissible limit.

Do PFAS changes in landfill leachate treatment systems correlate with changes in physical chemical parameters?

Per- and polyfluoroalkyl substances (PFAS) have been found at relatively elevated concentrations in landfill leachates. Some landfill facilities treat physical-chemical parameters of their leachates using on-site leachate treatment systems before discharge. The objective of this study was to evaluate whether changes in physical-chemical parameters of leachate at on-site treatment systems (including bulk measurements, oxygen demanding components, and metals) were associated with concentration changes in PFAS. Leachates were evaluated at 15 on-site treatment facilities which included pond systems, aeration tanks, powdered activated carbon (PAC), sand filtration, reverse osmosis (RO) and combination treatment processes. Results show that most physical-chemical parameters and PFAS were significantly reduced in RO systems (over 90 %). For pond systems, statistically significant correlations (rs > 0.6, p < 0.05) were observed between ∑26PFAS changes and the changes in pH, alkalinity, ammonia, and some metals. Significant correlations were also found between ∑8PFAAs precursors changes and specific conductivity (SPC), pH, alkalinity, ammonia, and metals changes. For aeration tank systems, significant correlations (rs > 0.6, p < 0.05) were observed between ∑26PFAS changes and changes in total dissolved solids and zinc, and between the changes of ∑8PFAAs precursors and field pH. These correlations are believed to be associated with rainfall dilution and precipitation of calcium carbonate and other metals as leachate is introduced to the atmosphere.

Pollution potential of dumping sites on surface water quality in Ethiopia using leachate and comprehensive pollution indices.

Municipal solid waste disposed of in illegal dumpsites pollutes the surface and groundwater. However, accurately determining these pollution levels is typically challenging for practitioners and decision-makers in developing countries. The purpose of this study is to use the leachate pollution index (LPI) to assess the contamination potential of uncontrolled dumping sites along the course of the Kulfo River in Arba Minch, Ethiopia. The comprehensive pollution index (CPI) approach was also utilized to assess the suitability of Kulfo River water quality for aquatic species. Leachate samples were collected from four uncontrolled dumping sites along the Kulfo River's course and analyzed for fifteen leachate characteristics necessary to quantify the LPI sub-indices. Water samples were taken from three monitoring stations along the river and examined for aquatic species suitability. When the leachate parameters were compared to the Indian limit for discharge of treated leachate, it was found that dumping sites posed a considerable risk of pollution to adjacent water resources. The overall LPI ranged from 23.34 to 27.35, which is higher than the discharge standard LPI of 5.69, indicating that dumping sites can threaten the surrounding water resources and human health. Based on the rating scale of CPI, at all monitoring stations, the river resulted severely polluted. Finally, appropriate strategies to reduce the pollution and the related mismanagement of solid waste were discussed. Combining LPI and CPI methods can represent a crucial tool for experts and decision-makers in developing countries to evaluate the pollution potential of dumping sites and water resource monitoring.

Comprehensive analysis and modeling of landfill leachate

Landfill leachate data compiled from 220 different landfills from 46 countries in Europe, Middle East, Asia, Africa, and America was analysed by multivariate statistical approaches. Data pre-treatment procedure such as handling of outliers, completion of missing data, and standardization of data was applied to prepare the raw data matrix for the complex statistical analyses including cluster and principal component analyses (PCA). Regression modeling was conducted to estimate leachate parameter values. Results show that usually inorganic parameters, if included in the PCA, dominated the first components indicating the highest correlations as well as accounting for majority of the variation in the data. Those highly correlated parameters in landfill leachate could be important in evaluation of their pathways into leachate in terms of transport and biodegradation mechanisms as well as their elimination potential from sampling and analytical procedures during monitoring activities at landfills. Some leachate parameters having significantly high concentrations, such as organics, salts, and some inorganics, impacted the formation of components in PCA. This in turn provides important information about the specific characteristics of leachate samples and the landfills to which they belong.

Development of Soil Substitutes for the Sustainable Land Reclamation of Coal Mine-Affected Areas

The main purpose of this paper was to outline a novel approach for the use of industrial by-products generated in coal mines and coal-fired power plants as the components for artificial soils. Several coal combustion by-products, coal mine waste and organic waste materials were tested at laboratory scale for use in the reclamation of areas degraded by coal mining activity. The role of artificial soils was the land rehabilitation of the high acidic waste heap. The results revealed that the amounts of organic matter (14.87–25.01%) and nutrients in the soil substitutes were sufficient to support plant growth, i.e., N (0.37–0.51%), P (0.23–0.47%), K (1.78–3.17%), Ca (4.93–8.39%) and Mg (1.16–1.71%). A phytotoxicity test using white mustard (Sinapis alba) seeds under laboratory conditions showed good germination results (56–66%) for three soil substitutes that did not contain fly ash from biomass combustion, compared to the reference soil (84%). The relationships established for the aqueous leachate parameters of soil substitutes vs. the Sinapis alba germination revealed negative correlations with electrical conductivity (r = −0.88), SO42− (r = −0.91) and Cl− (r = −0.70) ions; the two latter ones were responsible for the salinity which hampered the germination process of the soil substitutes. Moreover, quite similar correlations were obtained between the germination of Sinapis alba and the trace elements of the soil substitutes: Fe (r = −0.69), Cd (r = −0.72), Cu (r = −0.80), Pb (r = −0.78) and Zn (r = −0.74). However, negative and significant correlations in aqueous leachates were shown only with Ni concentration (r = −0.73). The relevance of these results for the effect of salinity on germination and the early growth of S. alba was discussed in detail and was confirmed with the Principal Component Analysis (PCA). The study proved that the physicochemical characteristic of recycled wastes exhibited their potential usefulness for the reclamation of affected areas such as mine waste heaps.