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The purpose of this paper is to compare various landfill gas (LFG) and leachate treatment technologies in a life‐cycle perspective.

Since a landfill causes emissions for a very long‐time period, life‐cycle‐based environmental assessment was carried out to compare different technological options for sustainable leachate treatment and LFG collection and utilization. WAMPS, the life‐cycle assessment (LCA) model for waste management planning, was used for the environmental assessment of selected leachate and LFG treatment technologies.

Results of both direct measurements in the studied landfills and LCA support the fact that leachate treatment with reverse osmosis has the best environmental performance compared to aerobic‐activated sludge treatment. Recently, the collection efficiency of LFG in the studied landfills is relatively low. In order to improve the overall environmental performance of LFG management the gas collection rate should be improved. LFG utilisation for energy recovery is an essential part of the system. The results of the study show that the avoided impacts of energy recovery can be even greater than direct impacts of greenhouse gas emissions from landfills. Therefore, measures which combine LFG collection with energy generation should be preferred to treatment in flare.

It should be noted that the results of this study do not express the total environmental impacts of the entire landfill system, but only the eutrophicating impacts and global warming related to the studied leachate and LFG management options. Therefore, it is recommended that further LCAs investigate also other relevant impact categories.

The results of LCA modelling show that it is important to ensure the highest collection and treatment efficiency of leachate and LFG, since poor capture compromises the overall environmental performance of a landfill.

The paper provides a site‐specific data on sustainable leachate and LFG management in selected Estonian conventional municipal solid waste landfills. As such, the paper contributes to the development of the regional reference input data for LCA in waste management.

The purpose of this paper is to investigate changes in the environmental state of Pääsküla landfill in the post‐closedown period, especially changes in the soil and groundwater quality, composition of leachate water and air quality, and to analyse the effects of the works carried out and the measures implemented during the closing down of the Pääsküla landfill on the surrounding environment.

The study is based on the official environmental monitoring reports (EERC 2005‐2009) combined with the practical work experience and observations of the author on the landfill.

The study reveals that the most evident changes, which have taken place in the environmental state in the Pääsküla landfill were those in the quality of surface water. Remarkable improvement of the water quality of the Pääsküla River was detected after installation of the vinyl pile wall around the landfill body. After capping of the landfill, a drop in the content of methane in landfill gas was detected, as well as a decrease of the total gas production in the landfill.

The conclusions justify the efforts made in the course of closing down works of the Pääsküla landfill and the chosen technical solutions. It is necessary to continue the environmental monitoring of the landfill leachate water, ground water and surface water as well as monitoring of air quality and subsidences on the landfill.

The paper provides a detailed overview of the post‐closedown environmental monitoring and maintenance activities in the landfill as well as progress in the state of environment regarding the measures taken in order to decrease the negative environmental impact of the landfill. The experience of closing down the landfill can be used for similar projects, especially the impacts of capping the landfill on the methane production and installation of the protection wall and leachate collection drainage around the landfill on the suface water.

The paper is an excerpt from a more comprehensive study by the Florida Department of Environmental Protection comparing the technical elements of offset projects in forestry, agriculture, and waste management, as well as some miscellaneous project types. The authors compare and contrast design elements of three specific offset projects: afforestation/reforestation, manure management, and landfill gas capture. The technical review for each offset project is concluded with a look at the potential applicability for that project in Florida in the context of the protocols evaluated.

Offset projects that may be employed in Florida are first broken up into comparable design elements specific to the selected offset project type. Focusing on the design elements, a discussion of the similarities and differences among the protocols for each offset project is presented. Each section begins with general findings then moves on to assessments of the detailed design elements. Finally, the project's general applicability to Florida is considered, highlighting specific strengths of particular protocols from the analysis of the design elements.

Protocols tend to vary from highly specific requirements to a more general set of recommendations. Interestingly, no one program's set of protocols is the most opportunistic for Florida, but rather various protocols may have distinctive strengths depending on the project type.

Many comparative studies of offset protocols evaluate protocols in the context of program‐level policies. This study uniquely values the technical details in the protocols and does not consider policy or program‐level issues.

The purpose of this paper is to examine a greenhouse gas (GHG) emission reduction potential from different waste management practices in Croatia. Energetic, environmental and economic benefits can be accomplished by utilizing municipal solid waste (MSW) and landfill gas as fuel in industry and energy sector, which is emphasized in this paper. The paper gives an overview of measures for energy recovery from MSW and landfill gas that could be implemented in Croatia. These measures also represent measures for an additional GHG emission reduction by decreased use of fossil fuels.

A methodology used for emission calculation (kinetic model) is explained. Three different scenarios of GHG reduction in waste management were defined. Implementation of best available techniques in waste management is envisaged by cross‐sectoral impact and effect of respective measures. Findings –This paper gives maximum achievable potential of GHG emission reduction with defined measure implementation dynamics. It was calculated that around one million ton of CO₂ can be avoided in 2020, which is 2.7 percent of projected GHG emissions in Croatia. The energy that could be recovered from waste (8.34 PJ in 2020) is relatively small in relation to the total final energy consumption in Croatia (about 3 percent).

The novelty of this work is achieved through integrated approach to GHG emission reduction and energy potential from MSW management in Croatia. The GHG reduction potentials are calculated by taking into account dependencies and interactions between the measures.

Explains the problems and opportunities created by the production of gas by decomposition in landfill sites. Describes the infrared and electrochemical methods by which gas can be detected and the typical manner in which these methods are applied. Also describes a PC‐controlled programmable sample system from Crowcon, which is designed for use in landfill sites.

Waste disposal is big business. Some 20 million tonnes of household and commercial waste is disposed of each year in the United Kingdom. A similar quantity of industrial waste — some of it hazardous — requires treatment and disposal. Household, commercial and industrial wastes as defined in the Control of Pollution Act 1974 are known as controlled wastes. In addition there are vast quantities of mining and quarry wastes. Approximately 90 per cent of all these materials is landfilled in its crude state. Much of the remainder is landfilled after treatment. Clearly, then, the proper selection, preparation, operation and aftercare of landfill sites is of paramount importance. Landfill is popular because it is significantly less costly than other methods of disposal — indeed it is the only option for a wide range of wastes. It must not, however, be regarded or perceived as a cheap and nasty option. Many professional disciplines and skills are involved in the sequence from site selection through to aftercare. Among these are geology, hydrogeology, property purchase, civil, mechanical and gas engineering, chemistry and agriculture. If landfill is to retain and deserve its pre‐eminent position, every step must be taken to the highest professional standards.

Describes the use of landfill for the disposal of waste and the gas generated by the waste. Details the engines fuelled by this gas and the special lubricants used to combat the aggressive chemicals some of the gases contain. Lists the properties of a proprietary range of natural gas engine lubricants.

In 1987, Campbell Soup Company introduced the Souper Combo, a line of frozen soup and sandwiches. Melvin Druin, vice‐president for packaging, called it “the perfect combination of old‐fashioned good taste and today's convenience. No mess. No fuss. Easy to use. All you have to do is clean your spoon. Everything else just throw away.” Unfortunately, the multi‐layered plastic‐coated packaging does not just disappear when thrown away. Plastics packaging, particularly from convenience products, has become a waste disposal nightmare. Garbage, an environmental magazine, gave the Souper Combo an “in the dumpster” award, saying, “It's precisely the kind of product that's created the municipal landfill monster.”

The purpose of this paper is to interrogate the fate of landfills as waste disposal option in Accra. This becomes imperative since for a long time, efficient disposal of waste remains a neglected issue and potential source environmental hazard.

The study adopted content analysis of literature, in-depth interview schedules with key stakeholders and direct field observations.

Landfills in Accra are in a state of ambivalence due to mismanagement. Improper designing and siting of dumpsites, often in close proximity to water sources and human settlements have created aesthetic and odour nuisances and increase health risks, attracting the wrath, disaffection and distrust of residents.

The study provides an insight into broader issues of landfills and demonstrates Accra's vulnerability to health hazard due to improper waste disposal, which becomes apparent with the least downpour and the subsequent flooding which exposes most drains as de facto receptacles for waste.

From all indications, Accra appears to be on the brink of a landfill void. Though this issue has been an open secret since 2000, it remains unattended to till date and calls for an immediate, well-planned and concerted attention.

This paper adopts qualitative research techniques to delve into a subject matter whose implication has citywide consequences. The method allows for in-depth assessment of the intent and commitment of all key stakeholders, which brings to the fore that landfills will no longer be the cheapest or simplest waste disposal option.

Landfill capping is a mandatory post closure procedure in Australia to isolate the deposited wastes from the outside environment, mainly water. Compacted clay caps are predominantly used in Australian landfills. Recent studies have shown that clay caps have shorter life span and fail to prevent percolation of water due to cracking. This paper aims to discuss a new technology called “Phytocapping” that has been trialled at Lakes Creek landfill in Rockhampton.

In this technique, trees were used as “bio‐pumps” and “rainfall interceptors” and soil cover as “storage” of water. The field performance of the phytocapping system was measured based on its ability to minimise water percolation into waste. Tree growth, transpiration, canopy rainfall interception and methane emission were monitored over three years. The percolation rate was modelled using HYDRUS 1D code for two different scenarios (with and without vegetation) for the thick (1,400 mm soil) and thin (700 mm soil) phytocaps respectively.

Results from the modelling showed percolation rates of 16.7 mm yr⁻¹ in thick phytocap and 23.8 mm yr⁻¹ in thin phytocap, both of which are markedly lower than those expected from a clay cap. Results from monitoring and observations showed that 19 of 21 tree species grew well in the harsh landfill environment. However, the correct species selection is very important for the long‐term sustainability of the phytocap. Results also show that phytocaps can reduce a significant amount of methane emission from landfills.

The cost of landfill capping is escalating and is putting a lot of financial and legal pressure on the small and medium sized local governments in Australia. The phytocapping technique not only offers financial benefits but also has some environmental and commercial benefits.

The paper focuses on a new technology being used in waste management.