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The aim of this work is to compare quality of leachates from regional municipal landfill in different seasons (dry, snowy/rainy) during a three-year monitoring period due to the fact that quality of landfill leachate can rapidly change under different conditions.

Raw leachates were sampled prior to biological treatment at different periods of the year (November 2007, March 2008, May 2008, March 2009, and January 2010) to detect the changes in their composition due to different physico-chemical conditions at the site (temperature, moisture, etc.). Leachates were physico-chemically characterized and the toxicity of chosen leachates was assessed by a battery of biotests.

Most of the investigated raw leachates exceed Slovenian effluent limits. Samples from March 2008 and March 2009 generally showed higher concentration of measured parameters and also higher toxicity. It has been confirmed that the physico-chemical parameters of leachates usually decrease during rainy/snowy seasons, in addition to the change in toxicity.

This paper demonstrates the need to evaluate the physico-chemical parameters and toxicity of landfill leachate during different seasons of the year to achieve an appropriate assessment of its environmental impact.

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.

Unfortunately in India, most landfills are located along the banks of rivers flowing through the cities. The interaction of two big, diverse and delicate ecological systems – rivers and landfills – has been investigated in this paper. During 2000, the estimated quantity of waste generation was more than 9,000 tons per day. This is one of the biggest sources of environmental degradation in Delhi, India's capital. It contributes to river pollution in a significant way through landfill leachate and runoff, especially during the rainy season. Since the 1950s over 12 large landfills have been packed with all sorts of non‐biodegradable and toxic wastes from Delhi. The area covered by landfills is at least 1 percent (14.83 sq.km) of Delhi's total area. All the landfill sites except Tilak Nagar, Hastal and Chattarpur are located close (0‐6 km) to the river Yamuna. Further, these landfills are not engineered sanitary landfills and the waste is dumped at open sites without proper compaction. A high mountain of waste can be seen at all landfill sites without a cover. The leachate produced by landfills finally percolates to the porous ground surface at the landfills or finds its way to nearby drains. A large portion of landfill leachate and runoff produced by these landfill sites finally reaches the Yamuna through ground water flow or surface water flow through the drains. The results of analysis by investigations and environmental mapping during the study clearly indicate that river water quality is affected by the presence of landfill locations, i.e. landfill leachate and landfill surface runoff.

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 most common form of municipal waste disposal in the EU continues to be landfilling, from which leachate could seriously contaminate ground water aquifers that serve as drinking water sources. Constructed wetland is considered as a sustainable option as it facilitates water recycling in landfill sites using closed loop technology. In Slovenia constructed wetlands have been successfully developed and there are already 6 landfills that have been remediated using this technique. An innovative co‐natural approach that has been applied on the landfill site at Ormoz (1.5ha), allows a landfill site to become a bioreactor by permitting controlled infiltration. Leachate is purified using a constructed wetland covering 1,000m². The average hydraulic load is 12m³/d. Purified water will then be recycled through an underground irrigation system to fast growing trees. We assume that this solution will allow rapid stabilisation of the landfill site as the infiltrated water in the landfill site stimulates microbes to mineralise organic waste. There is no risk of leaks as the root systems of trees follow the non‐uniform settling of waste. Owing to the closed hydrological and pollution cycle, the impact on the environment and especially the risk of water contamination will be reduced.

The purpose of this paper is to investigate the physico-chemical properties of the groundwater surrounding the Solous (solid waste dumpsite) at Isheri, Lagos, Nigeria.

In total, 40 groundwater samples were collected from ten pre-determined sampling stations. Three sample stations were established before the dumpsite; three sample stations were located in the vicinity of the dumpsite in the direction of the leachate plume, while the remaining four sample stations were situated further away and acted as a control. Sampling was carried out four times during the study period (twice each in the rainy and dry seasons). The parameters measured in situ were air and water temperatures (using mercury-in-glass bulb thermometer) and pH (using pH meter). Calcium and magnesium contents were measured using the Ca-Mg indicator; sodium content was measured using the flame emission spectrophotometry and phosphate was measured using the flame photometry. The selected heavy metals (copper, iron, lead, cadmium, zinc and manganese) were measured by using the atomic absorption spectrometer. The oxygen parameters, such as dissolved oxygen, biological oxygen demand, chemical oxygen demand and organic matter, were determined titrimetrically. The data obtained were subjected to descriptive statistics and analysis of variance (ANOVA).

The results showed that many parameters had higher values in the dry season than in the rainy season. Temperature (27.75±0.95°C), alkalinity (211.37±82.78 mg/LCaCO₃), phosphate (0.30±0.07 mg/L) and sulfate (2.78±0.35 mg/L), sodium ion (41.95±18.86 mg/L), dissolved oxygen (2.98±0.57 mg/L) and COD (33.54±4.50 mg/L) had higher mean values in the dry season than in the rainy season. On the other hand, the mean values of electrical conductivity (1,224.85±370.63), nitrate (0.01±0.003 mg/L), chloride (98.76±21.58 mg/L), calcium ion (5.38±0.68 mg/L), magnesium ion (3.05±0.05 mg/L), BOD (22.37±2.20 mg/L) and pH (6.31±0.18) were higher in the rainy season than in the dry season. The heavy metals (iron 1.10±0.05 mg/L, lead 0.12±0.07 mg/L, manganese 0.01±0.004 mg/L, copper 0.15±0.003 mg/L, zinc 0.07±0.004 mg/L and cadmium 0.02±0.02 mg/L) were fairly uniform all year round. There was also a marked decline in the values as one moved away from the dumpsite.

The implication of the findings is that human health is remarkably dependent upon safe and clean drinking water. Preserving the water resources and hindering them from pollution is preferred to the treatment of polluted water and rendering it suitable for consumption. The high electrical conductivity values obtained in the groundwater samples near the dumpsites are an indication of the effect of leachate on the groundwater quality. The high concentrations of dissolved solids in the groundwater may decrease the palatability and may cause gastro-intestinal irritation in humans, and laxative effect particularly on transits.

The pollutants from the various waste components disposed at the dumpsite percolate into the ground to pollute the groundwater. The groundwater is transported in the line of flow away from the vicinity of the dumpsite to pollute the groundwater in the area. The extent of contamination level of groundwater quality due to leachate percolation depends upon a number of factors like chemical composition of leachate, rainfall, depth and distance of the well from the dumpsite. Groundwater samples of different depths and distances from dumpsites were analyzed in the present study to understand the level of a combination.

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.”

Somerset County Council's landfill site at Wellington, near Taunton, is making extensive use of thermoplastic pipework from Durapipe for extraction of methane landfill gas and leachate.

The purpose of this paper is to assess sand-bentonite liners (SBL) which could be used as hydraulic barriers with a controllable quality, relatively low cost and easy operation in solid waste landfills.

These barriers have been used successfully in various applications and have attracted much attention in a short period of time. The only precautionary use of SBLs is related to the change of their hydraulic properties in high alkaline chemical environments. The main reason for this phenomenon is the presence of high ion exchange minerals in bentonite. By exposure to these environments, it is also laid open to degradation of the montmorillonite microstructure leads to change in hydraulic behavior. Three different compounds were used for laboratory-scale SBL, and diffusion was considered as the dominant mechanism of contamination transmission in these liners. Chlorine ion has been used as pollutant, and its diffusion coefficient was determined in the tested SBLs.

The sample’s diffusion coefficient for the first experiment containing 3% bentonite and 97% Semnan sand were 2.5 × 10^(−9) (m^2/s) and 2.44 × 10 ^(−9) (m^2/s), respectively. Similarly, for two samples with 6% bentonite and 94% Semnan sand, this parameter was equal to 2.17 × 10 ^(−9) (m^2/s) and 2.22 × 10 ^(−9) (m^2/s) and for two samples with 3% agglacial clay, 12% bentonite and 85% Semnan sand was 5.55 × 10 ^(−10) (m^2/s) and 6.11 × 10 ^(−10) (m^2/s). These values correspond to the range reported in previous studies. Also, it was observed that with comparing the diffusion coefficients of test, it was concluded that with increasing bentonite, the molecular diffusion decreases significantly.

In this study, three laboratory samples with different percentages of bentonite, clay and sand were considered and the results obtained from the laboratory were compared with the results obtained from numerical modeling.