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Tens of thousands of municipal solid waste (MSW) landfill sites worldwide hold a high risk of contaminating groundwater. This study aimed to establish a practical hydrogeological classification system for MSW landfill sites and explores the correlation between the classification and the risk of groundwater contamination. Hydrogeological information and groundwater contamination data from 80 MSW landfill sites in China were collected and analyzed, and a general hydrogeological model was proposed. The key hydrogeological parameters in the model were identified and analyzed, including the relative depth to the water table, the ratio of the length of the MSW site's recharge boundary to the combined length of the discharge boundary and hydrobalance boundary, the hydraulic conductivity of the bearing layer, and the background hydraulic gradient. On the basis of the general model, hydrogeological conditions at the landfill sites were categorized into seven subtypes. By using chloride, ammoniacal nitrogen and chemical oxygen demand as the characteristic contaminants, the migration features of groundwater contaminants within the seven subtypes of landfill sites were revealed. It was found that the maximum contaminant migration distance could be 2,000 and 300 m at the landfill sites with 'plain and intensive runoff' type and 'valley and weak runoff' type, respectively, and the corresponding concentration gradients of the characteristic contaminants were less than 10 mg/(L × m) and greater than 10 mg/(L × m). This work provides a guide for implementing cost-effective site investigation and environmental risk management at landfill sites with different types of hydrogeological conditions. [ABSTRACT FROM AUTHOR]

Remote sensing can represent an important instrument for monitoring landfills and their evolution over time. In general, remote sensing can offer a global and rapid view of the Earth's surface. Thanks to a wide variety of heterogeneous sensors, it can provide high-level information, making it a useful technology for many applications. The main purpose of this paper is to provide a review of relevant methods based on remote sensing for landfill identification and monitoring. The methods found in the literature make use of measurements acquired from both multi-spectral and radar sensors and exploit vegetation indexes, land surface temperature, and backscatter information, either separately or in combination. Moreover, additional information can be provided by atmospheric sounders able to detect gas emissions (e.g., methane) and hyperspectral sensors. In order to provide a comprehensive overview of the full potential of Earth observation data for landfill monitoring, this article also provides applications of the main procedures presented to selected test sites. These applications highlight the potentialities of satellite-borne sensors for improving the detection and delimitation of landfills and enhancing the evaluation of waste disposal effects on environmental health. The results revealed that a single-sensor-based analysis can provide significant information on the landfill evolution. However, a data fusion approach that incorporates data acquired from heterogeneous sensors, including visible/near infrared, thermal infrared, and synthetic aperture radar (SAR), can result in a more effective instrument to fully support the monitoring of landfills and their effect on the surrounding area. In particular, the results show that a synergistic use of multispectral indexes, land surface temperature, and the backscatter coefficient retrieved from SAR sensors can improve the sensitivity to changes in the spatial geometry of the considered site. [ABSTRACT FROM AUTHOR]

With the ever-increasing human population, there is a need to develop new urban settlements for human habitation. For these new settlements, it is imperative to optimally site different land-use zones, including solid waste disposal sites. The aim of this article is to determine suitable sites for locating a landfill in a new developed city in Zimbabwe around Mt. Hampden, named the New City. The New City will have various residential, commercial, and industrial areas. This entails the need for a proper site selection of a landfill to reduce the negative social and environmental effects such as contamination of water bodies and proliferation of diseases such as malaria. GIS and remote sensing were the major methods used in mapping the suitable areas. Multi-criteria evaluation and weighted overlay analysis methods were used in the landfill site selection process. Factors used for landfill site selection were rivers, settlements, roads, protected areas, and soils. A suitability map was generated, showing five potential sites that are suitable for landfill siting in the New City. Moderately suitable areas cover approximately 8%. A further 73% of the total land area in the study area is highly unsuitable for siting a landfill. A real-time Web-GIS monitoring interface was developed to monitor land use on the selected area, because the New City is a new area under development. Using a Web-GIS interface makes data easily accessible to environment planners, ecologists, spatial land planners, and other decision makers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Characterization of MIBA from 3 MSWI plants in Delhi to assess disposal or reuse. • Compilation of 50 studies on MIBA leaching to identify CoCs critical to fate of MIBA. • Comparative assessment of CoCs to evaluate variability across countries. • Emphasis on mandatory inclusion of the identified CoCs in future studies. Present study characterizes municipal solid waste incineration bottom ash (MIBA) from three incineration plants in Delhi with an intent to serve the dual objectives: a) assessing the disposal/reuse options for Delhi MIBA, b) evaluating variability in results across the countries (including India) and assessing if is significant enough to influence the fate of MIBA of varied origin. A review on leaching studies of MIBA (50 research papers) was conducted which aided in achieving both the objectives. Delhi MIBA samples were analysed for chemical composition. The two commonly adopted leaching tests i.e., TCLP and EN 12457–2, were conducted and the results were checked against regulatory threshold levels (RTLs) to achieve the first objective. Leaching concentration of the contaminants was compared with the compiled literature and RTLs to accomplish the second objective. The compendium of literature most importantly revealed the physicochemical parameters which are pivotal in determining the fate of MIBA but have been missing from many studies. Ten such parameters were identified: Cr, Cu, Mo, Sb, Cl - , SO 4 2- , Cd, Pb, Ni and Zn and are referred as contaminants of concern (CoCs). Delhi MIBA was found suitable for disposal to non-hazardous waste landfills and unsuitable for unrestricted reuse. CoCs identified in Delhi MIBA were identical to those observed in literature (except Cd, Pb and Zn). The variability in leaching concentration of CoCs, observed from comparative assessment of results, spanned nearly 2 to 3 log 10 magnitudes for Cu, Cr, Pb, Sb and Zn while 1 to 2 log 10 magnitudes for Mo, Cl - and SO 4 2-. [ABSTRACT FROM AUTHOR]

This study presents the utilisation of finely ground construction and demolition waste (CDW) as partial replacement (5–15 wt.%) to sulphide tailings on the short- and long-term strength, durability (i.e. no loss of strength) and microstructural properties of cemented paste backfill (CPB) over a curing period of 360 days. The CPB samples containing CDW were prepared at binder dosages of 7.5 and 8.5 wt.%, while control samples (full tailings) were only produced at 8.5 wt.% binder dosage. A total of 108 CPB samples were subjected to the unconfined compressive strength (UCS), acid/sulphate (pH, SO 4 2− ) and microstructure (MIP, XRD etc.) tests. Despite its limited contribution to the resistance of CPB to acid and sulphate attack, the use of CDW as partial replacement (5–15 wt.%) to sulphide tailings enhanced the strength properties of CPB samples by decreasing the total and macro porosity. The UCSs and pH values of CPB samples increased with increasing the CDW content in CPB mixtures, while the generation of sulphate ions (SO4 2− ) decreased irrespective of the binder dosages. Compared with control samples prepared at 8.5 wt.% binder dosage, 5.3–19.5% higher UCS values were obtained for the CPB samples containing 15 wt.% CDW prepared even at 7.5 wt.% binder dosage. Mercury intrusion porosimetry (MIP) analyses proved the beneficial effect of the use of CDW on the microstructural properties (i.e. total porosity) of CPB. These findings suggest that CDW materials can be suitably used as backfill material in the mining industry to fill underground voids created during the ore production. This offers safe disposal and hence environmentally sound management of CDW. [ABSTRACT FROM AUTHOR]

Though debates about the negative impact landfill exerts on land and property values are by no means historically new, research into the case of developing countries has only recently begun. This article attempts to synthesise existing literature on the subject through the analysis of three case studies to enhance our understanding, especially the contextual conditions surrounding the relationship. Applying this theoretical framework to the disposal practices occurring in three cities in Ghana, this article offers insight into the culpability of landfills in negatively impacting property values. In an illuminating analysis, we argue that most engineered landfills in the country serve as a catalyst in correcting the ills of uncontrolled urbanisation (governance, attitudinal and financial constraints, etc.). We opine that landfills’ relationship with host communities must be understood in relation to our overall underdevelopment, coupled with the increasing economic and technical challenges shaping much of the country’s history. [ABSTRACT FROM PUBLISHER]

Background and aims: One of the most important environmental problems is excessive production and management of municipal solid waste materials. Environmental Impact Assessment (EIA) is considered as an important strategy to minimize negative impacts. The aim of this study was the use of the EIA process to minimize environmental impacts of Shahrekord landfill and to provide appropriate options for managers and planners. Methods: This descriptive-analytical study was performed to assess environmental impacts of Shahrekord solid waste landfill using two methods, Rapid Impact Assessment Matrix (RIAM) and Iranian Matrix based on field observation and data collection. Comparing was included four existing options including: continue the current landfill practices, upgrade landfill, construct a new sanitary landfill and compost and recycle plant. Results: The score of continuing current practices at RIAM and the Iranian Matrix was -1443 and -3.9, respectively. Composting and recycling plant has -816 score in the RIAM and 1 in Iranian matrix. Moreover, the results of two methods were displayed different in priority for upgrade landfill and construction a new landfill. Conclusion: Based on both methods to continue landfill with current practices is accompanied by severe damage in terms of environmental and health position. Composting and recycling plant is the first priority for Shahrekord. [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]

Abstract: Open dumping is the most common practice for the disposal of urban solid wastes in the least developed regions of Africa, Asia and Latin America. Sanitary landfill design and operation has traditionally focused on large cities, but cities with fewer than 50,000 in population can comprise from 6% to 45% of a given country’s total population. These thousands of small cities cannot afford to operate a sanitary landfill in the way it is proposed for large cities, where heavy equipment is used to spread and compact the waste in daily cells, and then to excavate, transport and apply daily cover, and leachate is managed with collection and treatment systems. This paper presents an alternative approach for small cities, known as the semi-mechanized trench method, which was developed in Villanueva, Honduras. In the semi-mechanized trench method a hydraulic excavator is used for 1–3days to dig a trench that will last at least a month before it is filled with waste. Trucks can easily unload their wastes into the trench, and the wastes compact naturally due to semi-aerobic biodegradation, after which the trenches are refilled and covered. The exposed surface area is minimal since only the top surface of the wastes is exposed, the remainder being covered by the sides and bottom of the trench. The surplus material from trench excavation can be valorized for use as engineering fill onsite or off. The landfill in Villanueva has operated for 15years, using a total land area of approximately 11ha for a population that grew from 23,000 to 48,000, with a land requirement of 0.2m2/personyear, a cover to waste ratio of 0.2, and an estimated soil surplus of 298,000m3 that is valorized and used onsite. The landfill has been operated solely by the municipality with an operational cost in 2010 estimated at US$4.60 per ton. A modified water balance analysis at Villanueva shows negligible leachate generation from covered trenches and 700m3/yr (60m3/hayr) from the two open trenches required for daily operation. If the site were an open dump, however, leachate generation is estimated to be 3900m3/hayr and contaminated runoff 5000m3/hayr. A simple model used to estimate dilution of generated leachate based on groundwater flow data and aquifer stratigraphy suggests that the leachate will be diluted by a factor of 0.01 in the aquifer. Leachate contaminants will not accumulate because the aquifer discharges to the Ulua River 2km south of the landfill. While not suitable for all sites, the Villanueva method nevertheless serves as an excellent example of how a small city landfill with natural compaction of waste and attenuation of leachate can be sustainably operated. [Copyright &y& Elsevier]

Fibre reinforced polymers (FRPs) are increasingly being used in construction due to their light weight, ease of installation, low maintenance, tailor made properties, and corrosion resistance. The UK FRP industry produces 240,000 tonnes of products a year with 11% of this being for the construction industry in a variety of structural and on-structural applications. Products made from FRP materials can offer significant environmental benefits, for example, FRPs used in bridges can reduce the overall weight of the structure and so offer reduced transport and installation impacts. However, although the in service environmental benefits of composites are known, there is far less understanding of the environmental and social implications associated with the manufacture of FRP materials and products. Current and impending waste management legislation will put more pressure on the industry to address the options available for dealing with FRP waste. Such waste legislation focuses on dealing with waste through the w aste hierarchy and will therefore put more pressure on solving FRP waste management through recycling and reuse. At present the most common disposal method for UK FRP waste is landfill. To assist in the transition from disposal in landfill to recycling, the FRP industry needs to consider designing materials and components for easier deconstruction, reuse and recycling at the end of the product life. This paper will highlight the key issues affecting the FRP industry, taking a cradle to grave approach and assessing the environmental impacts at each stage. [ABSTRACT FROM AUTHOR]

Abstract: Results from physical experiments are presented to assess the possible puncture of a 1.5-mm-thick HDPE geomembrane and, if not punctured, the maximum tensile strains in the deformed geomembrane from intentionally placed stone particles in an underlying compacted clay liner when subjected to applied vertical stresses. The influences of applied pressure, clay water content, stone size, stone burial depth and protection layer on the geomembrane tensile strains are reported. Except in one test conducted to a pressure of 2000kPa, the geomembrane was not punctured in the short-term tests conducted; however, it was subjected to local indentations and tensile strains from the underlying gravel particles that may exceed proposed allowable long-term strain limits. Tensile strains for the specific 35mm stones tested when initially flush with the clay surface were negligible, even up to pressures of 1000kPa, provided the initial water content of clay was 12%. Increases in water content or stone size were found to increase the tensile strain. Placing the clay at the lower limit of acceptable water content was found to be beneficial in terms of reducing strains from buried stones; however, this was also found to make the geomembrane more susceptible to stone particles sitting on top of the clay surface and hence careful site inspection is required to remove all visible stones that sit on top of the clay surface. [Copyright &y& Elsevier]

This paper presents a laboratory investigation of hydraulic conductivity of municipal solid waste (MSW) in landfills and provides a comparative assessment of measured hydraulic conductivity values with those reported in the literature based on laboratory and field studies. A series of laboratory tests was conducted using shredded fresh and landfilled MSW from the Orchard Hills landfill (Illinois, United States) using two different small-scale and large-scale rigid-wall permeameters and a small-scale triaxial permeameter. Fresh waste was collected from the working phase, while the landfilled waste was exhumed from a borehole in a landfill cell subjected to leachate recirculation for approximately 1.5 years. The hydraulic conductivity tests conducted on fresh MSW using small-scale rigid-wall permeameter resulted in a range of hydraulic conductivity 2.8×10-3–11.8×10-3 cm/s with dry unit weight varied in a narrow range between 3.9–5.1 kN/m3. The landfilled MSW tested using the same permeameter produced results between 0.6×10-3–3.0×10-3 cm/s for 4.5–5.5 kN/m3 dry unit weights. The hydraulic conductivity obtained from large-scale rigid-wall permeameter tests decreased with the increase in normal stress for both fresh and landfilled waste. The hydraulic conductivity for fresh MSW ranged from 0.2 cm/s for 4.1 kN/m3 dry unit weight (under zero vertical stress) and then decreased to 4.9×10-5 cm/s for 13.3 kN/m3 dry unit weight (under the maximum applied normal stress of 276 kPa). The hydraulic conductivity of the landfilled MSW decreased from 0.2 cm/s to 7.8×10-5 cm/s when the dry unit weight increased from 3.2 to 9.6 kN/m3. The results clearly demonstrated that the hydraulic conductivity of MSW can be significantly influenced by vertical stress and it is mainly attributed to the increase in density leading to low void ratio. In small-scale triaxial permeameter, when the confining pressure was increased from 69 to 276 kPa the hydraulic conductivity decreased from approximately 10-4 to 10-6 cm/s, which is much lower than those determined from rigid-wall permeameter tests. The published field MSW hydraulic conductivities are found to be higher than the laboratory results. Landfilled MSW possesses lower hydraulic conductivity than fresh MSW due to increased finer particles resulting from degradation. The decreasing hydraulic conductivity with increasing dry unit weight is expressed by an exponential decay function. [ABSTRACT FROM AUTHOR]

The article presents abstracts on city planning-related topics, including visions of waterfront development in postindustrial Philadelphia, the construction of a town planning perception of Colombo, and city planning and the U.S. census.

Abstract: A method to record the shape, size, and spacing of gravel contacts that act on a geomembrane from an overlying granular drainage layer is presented. The gravel contacts acting on a 1.5-mm thick, high-density polyethylene geomembrane are then quantified for two poorly graded, angular gravels (GP1 and GP2 with nominal grain sizes of 50 and 25mm) with compacted clay beneath the geomembrane and when subjected to an applied pressure of 250kPa. The geomembrane indentations and strains are also reported. Five types of contacts were defined: point, edge, area, perimeter and composite. Point contacts were the most frequent and, along with edge contacts, caused the steepest indentations and the largest strains. The average spacings between gravel contacts were found to be 55mm for GP1 and 37mm for GP2. Without a protection layer, the largest tensile strains in the geomembrane were 32 and 16% for GP1 and GP2, respectively. A nonwoven needle-punched geotextile was found to reduce the contact pressure acting on and the resulting strains in the geomembrane. However, none of the geotextiles tested (with masses up to 2240g/m2) were able to limit the tensile strains below proposed allowable levels for long-term strain even for the short-term conditions examined. [Copyright &y& Elsevier]

Presents several abstracts featured in various journals as of August 2006. "Creating the Public Domain: Nineteenth-Century Local State Formation in Britain and the U.S.," by Alan Digaetano; "The Significance of Color Declines: A Re-Analysis of Skin Tone Differentials in Post-Civil Rights America," by Aaron Gullickson; "Deconstructing the City of Culture: The Long-Term Cultural Legacies of Glasgow 1990," by Beatriz García.

Nowadays, health-care waste management is a challenging issue for both the public and government sectors because it contains infectious, radioactive, or hazardous waste. Selecting a suitable method for health-care waste disposal is known as a complex decision-making problem due to the existence of several multiple criteria that may in conflict with each other. In this paper, we propose a novel method called evaluation based on distance from average solution framework based on parametric divergence measures with the context of intuitionistic fuzzy sets to evaluate and rank the health-care waste disposal alternative. To do this, first, novel parametric intuitionistic fuzzy divergence measures are developed, and various desired properties have also been examined. Second, the decision experts are evaluated, and the criteria weights are computed by developed parametric divergence measure method. Third, the preference order of the alternatives is illustrated by the developed framework. The proposed framework is based on the positive and negative distances from the average solution. Moreover, the health-care waste disposal alternative selection problem is considered to elucidate the applicability of the proposed framework. Four health-care waste disposal alternatives, including incineration, steam sterilization, microwave and landfill disposal, are considered in this study. The health-care waste disposal alternatives considered in this study include. The outcome illustrates that, the steam sterilization was the highest appraisal score (0.7025) and therefore, it should be chosen as the most suitable health-care waste disposal method in this study. Also, a comparison with existing approaches is shown to illustrate the validity and practicability of the developed framework. Image 1 • Extended a new EDAS approach under intuitionistic fuzzy set called IF-EDAS. • A new IF-EDAS approach is proposed to evaluate health-care waste disposal. • Novel parametric divergence measures for intuitionistic fuzzy sets are developed. • To evaluate weights of criteria, new parametric divergence measures is implemented. • A real health-care waste disposal evaluation problem is considered. [ABSTRACT FROM AUTHOR]

This study was performed in order to evaluate the effect of the leachate from a landfill, in the Athens region (Greece), on the underground water of the surrounding area A field study was performed and various samples were taken from various wells in a way that an area up to3 km from the landfill was covered. The physical chemical characteristics of the underground water were measured. The experimental results indicate that the underground water has been greatly affected by the leachate, since most of the parameters examined show increased concentrations which are very much related to the leachate characteristics. [ABSTRACT FROM AUTHOR]