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Managing waste tires presents a significant challenge globally, particularly in regions experiencing high temperatures and shortage of landfill sites. This issue is affecting countries like Kuwait, where the abundance of waste tires is a major source of environmental and safety risks, particularly during the intensely hot summer months. This extreme heat has sparked numerous fires, leading to substantial air pollution due to thick black smoke. Given the limited disposal options, recycling waste tires and finding practical applications for ground tire rubber (GTR) is essential. To address the challenge, a comprehensive laboratory testing program was conducted, using locally produced rubber aggregates as an additive to Kuwait's local surface sands. Two new variables were examined namely the size and gradation of the GTR, and the density of the compacted mixes. For this purpose, two different sizes of rubber aggregates, fine and coarse produced locally, were utilized, and the impact of relative compaction on the strength and compressibility of the mixtures was investigated by testing samples compacted to the maximum density and to 95% of the maximum density. The results suggest that combining local surface sands with rubber tire additives results in a lighter, more permeable, and compressible material, contributing significantly to sustainable waste management. With 20% rubber additive the maximum dry density decreased by nearly 20%, and the permeability increased by 1.74–3.11 times and the compression index increased by 6.15 and 3.8 times with fine and coarse rubber respectively. The angle of friction remained unchanged at 36° with the addition of coarse rubber and decreased by 3°–4° with fine rubber. The change in behavior although not an increase in the strength and stiffness, offers a range of suitable practical applications in civil engineering and environmental management, including use as a drainage layer, embankment construction on soft ground, earth fill around retaining walls, an additive in asphalt mixes, and in manufacturing compressible tiles for sports facilities. [ABSTRACT FROM AUTHOR]

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Increasing population in the developing countries tend to generate more quantity of solid wastes, which are to be disposed through the proper Solid Waste Management (SWM). Landfill is one of the most common methods in SWM used for the disposal of solid wastes. However, evaluating the suitable site for establishing a landfill is more complex due to the integration of multi-factors. In such conditions, GIS-based Multi-Criteria Evaluation (MCE) techniques play a major role in incorporating various factors and guidelines for identifying the suitable landfill site. Thus, the present study is conducted to select the suitable site for establishing a landfill in Thiruverumbur taluk of Tiruchirappalli district. For which, various factors (cultural, physical, demographic and environmental) and sub-factors (geomorphology, geology, soil texture, slope, settlement proximity, road proximity, rail proximity, industrial proximity, land use/land cover, NDVI, population density and household density) were utilised. The weights of level 1 and level 2 factors were determined using Analytical Hierarchical Process (AHP) and the ratings for each class were obtained through fuzzy linear membership. Based on the weights and ratings, the Solid Waste Landfill Suitability Index (SWLSI) of has been derived and the SWLSI values indicates 15.29% of the study area is very highly suitable; 25.4%, highly suitable; 28.8%, moderately suitable; 19.6, low suitable and 10.7% very low suitable for situating a site for landfill use. Furthermore, based on the results and field observations, two candidate sites of landfill were proposed for the societal development. [ABSTRACT FROM AUTHOR]

Disposal of solid waste is a challenging task in developing countries as this type of waste can seriously degrade the environment and pose threat to human health. To mitigate the environmental impact, appropriate techniques must be used in accordance with standards for the disposal of solid wastes. Leachate that originates from the decomposition of solid waste within waste disposal dumping sites and landfills may infiltrate into soil, groundwater and surface water resulting in contamination. A combination of clay materials and geomembrane has been widely utilized as a suitable permeability barrier to prevent contamination. In the case of uncontrolled landfills, leachate may be responsible for serious and irreversible pollution. According to the standards utilized in Turkey, the thickness of the clay layer used as an impermeable material is 60 cm, which is constructed as two 30 cm thick compacted clay layers. This paper evaluates the optimum clay thickness to prevent leachate contamination of soil or water. Experimental models were prepared involving 20, 40, 60 and 80 cm thick clay layers with 20 cm height leachate to determine the optimum clay thickness permeability barrier for a waste disposal dumping site. The initial results indicate that a 40 cm thick clay layer is sufficient as an impermeable barrier in these sites. [ABSTRACT FROM AUTHOR]

Since the mid 1980s, Naples and the Campania region have suffered from the dumping of wastes into overfilled landfills. The aim was to characterise a former cave located in Roccarainola (Naples, Italy) for its eventual destination to a controlled landfill site. A detailed hydro-geochemical survey of the area was carried out through drilling of 14 boreholes and four monitoring wells. Samples of water, sediment and soil were analysed for heavy metals and organic contaminants from a dew pond placed in the middle of the cave. The underneath aquifer was also surveyed. The nature of gases emitted from the site was investigated. Results of the geognostic survey revealed the presence of huge volumes of composite wastes, approximately half a million of cubic metre, which accumulated up to a thickness of 25.6 m. In some points, wastes lie below the free surface level of the aquifer. The sampled material from the boreholes revealed levels of As, Cd, Cr, Cu, Hg, Pb, Sn, Tl and Zn exceeding the intervention legal limits. Outstanding loads of Cd, Pb and Zn were found, with levels exceeding of about 50, 100 and 1,870 times the limit. In several points, polycyclic aromatic hydrocarbon load was extremely high, 35 vs 1 mg kg-1 of the threshold. The aquifer was also very heavily polluted by Cd, Cr-tot, Cu, Fe, Mn, Ni, Pb and Zn, with impressive high load of Cr and Mn, up to 250-370 times the limits. Hot gases up to 62 °C with presence of xylene and ethylbenzene were found. Results indicated that the site needs an urgent intervention of recovery to avoid compromising the surrounding areas and aquifers of the Campania plain. [ABSTRACT FROM AUTHOR]

The present work demonstrates the environmental problems associated with the development and operation of a lined and unlined landfill site, both used for municipal solid waste landfilling, that are situated next to the city of Patra, Greece. Findings from a detailed site investigation as well calculations on hydrologic evaluation of landfill’s performance and measurements on leachate composition proved that the lined landfill site is more secure and environmental friendly compared with the unlined landfill site. Even though, until today, there is no evidence from near boreholes for severe contamination problems generated by any of the two landfills, in the forthcoming future several environmental problems are expected to occur from the unlined site. In addition the prevailing hydrogeotechnical conditions indicated that the unlined site is a potential source of contamination; hence extra remedial measures should be received by the local authorities to prevent severe contamination in soil and groundwater. [ABSTRACT FROM AUTHOR]

Goal, Scope and Background. The aim of the present study is to evaluate, through LCA, the potential environmental impact associated to urban waste dumping in a sanitary landfill for four case studies and to compare different technologies for waste treatment and leachate or biogas management in the framework of the EPD® system. Specific data were collected on the four Italian landfills during a five-year campaign from 2000 to 2004. This work also analyses the comparability of EPD results for different products in the same product category. For this purpose, a critical review of PSR 2003:3, for preparing an EPD on 'Collection, transfer and disposal service for urban waste in sanitary landfills', is performed. Methods. PSR 2003:3 defines the requirements, based on environmental parameters, that should be considered in an LCA study for collecting and disposal service of Municipal Solid Waste (MSW) in a sanitary landfill. It defines functional unit, system boundaries towards nature, other technical systems and boundaries in time, cut-off rules, allocation rules and parameters to be declared in the EPD. This PSR is tested on four case studies representing the major landfills located from the farthest west to the farthest east side of the Ligurian Region. Those landfills are managed with different technologies as concerns waste pre- treatment and leachate or biogas treatment. For each landfill, a life cycle assessment study is performed. Results and Discussion. The comparison of the LCA results is performed separately for the following phases: transport, landfill, leachate and biogas. The following parameters are considered: Resource use (Use of non-renewable resources with and with- out energy content, Use of renewable resources with and with- out energy content, Water consumption); Pollutant emissions expressed as potential environmental impact (Global Warming Potential from biological and fossil sources, Acidification, Ozone depletion, Photochemical oxidant formation, Eutrophication, Land use, Hazardous and other Waste production). The com- parison of the LCA results obtained for alternative landfill and biogas management techniques in the case studies investigated shows that the best practicable option that benefits the environ- ment as a whole must be identified and chosen in the LCA context. For example, a strong waste pre-treatment causes a high biological GWP in the landfill phase, but a low GWP contribution in the biogas phase, due to the consequent low biogas production, evaluated for 30 years since landfill closure. Conclusion. The analysis of four case studies showed that, through the EPD tool, it is possible to make a comparison among different declarations for the same product category only with some modification and integration to existent PSR 2003:3. Results showed that different products have different performances for phases and impact categories. It is not possible to identify the best product from an environmental point of view, but it is possible to identify the product (or service) with the lowest impact on the environment for each impact category and resource use. Recommendation and Perspective. In consequences of the verification of the comprehensiveness of existent PSR 2003:3 for the comparability of EPD, some modifications and integration to existent rules are suggested. [ABSTRACT FROM AUTHOR]

Evaluation of 12 years of landfill leachate chemical data from a lined cell of municipal waste in south Florida, USA shows an overall declining trend in major ion chemistry. The leachate is dominantly Cl, Na, HCO3 and organic solutes. There are significant short-term variations in concentration that appear to be related to rainfall, rather than fundamental changes to leachate composition. Inorganic parameters related to pH, such as alkalinity, calcium, and magnesium appear to be chemically buffered. Chromium, cobalt, vanadium, zinc, and the metalloid boron display significant short-term co-variance with a decreasing trend. Iron and manganese concentrations increased significantly after capping. Based on the predominance of ammonia, historic methane generation, and increasing trends for iron and manganese after closure, the landfill cell has an anaerobic (reducing) interior environment. The reducing conditions were enhanced by capping and caused the most redox sensitive metals (manganese and iron) to become more mobile. [ABSTRACT FROM AUTHOR]

The behavior of a municipal waste landfill on marine clay was analyzed from field measurement data. Instruments, e.g., a groundwater level sensor, piezometer, earth pressure gauge, settlement plates, inclinometer, etc., were installed and operated during the disposal period from October 1992 to November 2000. A database system was developed to manage the data from this landfill using Access (Microsoft) with Delphi programs. From the analyses, it was determined that the settlement of the landfill during the initial period of waste disposal was small because of the high leachate level in the landfill. As the level of waste became higher than the leachate level, the settlement of the landfill increased significantly due to the increasing effective pressure within the landfill. From a stability point of view, the critical time for the landfill in this study was the initial period of landfill disposal, which was caused by either the impact load of waste disposal or the time schedule of waste disposal, which was faster than the consolidation of foundation clay caused by the waste load. [ABSTRACT FROM AUTHOR]

Until a hundred years ago, the waste products from human activities were returned into the environment and underwent the biosphere's natural elimination processes without there being any long-term charge on the environment. During the last century, the increase in the amount of refuse has been accompanied by a decrease in its quality, mainly due to the production and dispersal of heavy metals and xenobiotic compounds. Both useful and noxious microbial processes have been underestimated in applied research in the field of waste management which, until now, has dealt mainly with artificial technologies. This paper presents some examples of microbiological processes occurring in waste treatment, particularly dumping, waste incineration, composting and biomethanization. [ABSTRACT FROM AUTHOR]

Identification of suitable landfill sites for the sake of public health is a critical issue which has been addressed in the present study. Sites that are far away from settlements minimize public health problems. In the present study, suitable landfill sites with minimum hazards for environment and public health for Islamabad and Rawalpindi city of Pakistan were identified through analytical hierarchy process, which is a useful technique for the identification of suitable landfill sites with minimum influence on environment, ecology, economy and public health. Afterward, least cost path analysis in GIS was chosen for selection of most suitable landfill site. The environmental (groundwater, surface water, vegetation, soil type and environmental sensitive areas), social (roads, slope) and economic (settlements, airports, railways) factors were taken into consideration and were prioritized with pair-wise comparison and weighted sum analysis. Initially twelve sites were found very highly suitable for landfill site. After ground truthing, seven sites were identified as very highly suitable with total area of 1108 ha complied with prerequisite factors for locating landfill site. Latter least cost path analysis led to identification of four most suitable sites for landfill site. The proposed landfill sites have been sited with maximum accuracy in order to help management authorities to select the more suitable areas and so helping the decision makers in solving waste management problems with minimum pollution and public health risks. [ABSTRACT FROM AUTHOR]

The paper considers a dynamic model in which an income stream, growing over time, is optimally divided into consumption and expenditures on waste disposal, the latter being optimally divided between 'recycling' and 'landfilling.' Recycling is thought of as a 'backstop' wastedisposal technology - it does not require landfill space but is a relatively expensive method of waste disposal. Landfilling uses up scarce landfill capacity. While conserving landfill space is the major reason the municipality recycles, another motive for recycling might bethat recycling itself generates utility. Our analysis suggests that the optimal recycling program varies considerably with both landfill capacity and initial income. For example, richer municipalities are likely to introduce recycling much earlier in the planning period thanpoorer municipalities. Thus when legislating recycling, national or regional governments must be sensitive to the differences between municipalities. [ABSTRACT FROM AUTHOR]

In Germany, landfilling and incineration are the main techniques forthe disposal of waste. However, due to humid climatic conditions, leakage of contaminated water from landfills into the subsurface poses a considerable threat to the environment. Therefore, the German states require high safety standards for the construction of a landfill. Emphasis is put on the presence of natural geological barrier rocks. Clay and silts, claystones and siltstones are best suited to meet the requirements defined in legal waste regulations. With regard to retardation capacity, thickness is considered of higher importance than hydraulic permeability. Suitable areas have to be reduced by legally excluded areas. A site search program in Lower Saxony revealed that only 1% of the total state area falls into the best suitability category. Geoscientific investigations on the remaining suitable areas have to become more detailed in the search progress. Geographical information systems (GIS) are the most adequate tools to work on all involved data and to present and outline the results. GIS make the results transparent and understandable to the public. These investigations are anecessary part of the environmental impact assessment which is obligatory for a landfill site's construction. Criteria catalogues take all important aspects of the search process into consideration and helpto find the most suitable site. [ABSTRACT FROM AUTHOR]

Since the beginning of the 1980s waste disposal has become a particularly sensitive issue. This has led to the development of new legislations in the European Community and internationally which resulted inan array of regulations concerning landfill liner design. This papercomments on different 'engineered' containment methods with particular reference to landfill liner design. Suggestions based on the review of the different methodologies are given and a case study is presented. [ABSTRACT FROM AUTHOR]