A decision support tool for landfill methane generation and gas collection

This study presents a decision support tool (DST) to enhance methane generation at individual landfill sites. To date there is no such tool available to provide landfill decision makers with clear and simplified information to evaluate biochemical processes within a landfill site, to assess performance of gas production and to identify potential remedies to any issues. The current lack in understanding stems from the complexity of the landfill waste degradation process. Two scoring sets for landfill gas production performance are calculated with the tool: (1) methane output score which measures the deviation of the actual methane output rate at each site which the prediction generated by the first order decay model LandGEM; and (2) landfill gas indicators’ score, which measures the deviation of the landfill gas indicators from their ideal ranges for optimal methane generation conditions. Landfill gas indicators include moisture content, temperature, alkalinity, pH, BOD, COD, BOD/COD ratio, ammonia, chloride, iron and zinc. A total landfill gas indicator score is provided using multi-criteria analysis to calculate the sum of weighted scores for each indicator. The weights for each indicator are calculated using an analytical hierarchical process. The tool is tested against five real scenarios for landfill sites in UK with a range of good, average and poor landfill methane generation over a one year period (2012). An interpretation of the results is given for each scenario and recommendations are highlighted for methane output rate enhancement. Results demonstrate how the tool can help landfill managers and operators to enhance their understanding of methane generation at a site-specific level, track landfill methane generation over time, compare and rank sites, and identify problems areas within a landfill site

Assessment of municipal opened landfill and its impact on environmental and human health in central Thailand

Purpose: Non-sanitary landfill or open dumping stored both non-hazardous and hazardous waste disposed from households, restaurants, agricultural activities, and industrial sectors that could contaminated to the environment. This study aimed to assess the environmental status and its impact of opened solid waste landfill located nearby agriculture and natural resources in municipal area of central Thailand. Methods & Materials: Soil and water samples were collected from six locations of landfill and surrounding areas such as paddy field and water reservoir at two-month interval for six consecutive months. Heavy metal contamination and quality of soil and water including physical, chemical, biological parameters were analyzed by using standard methods. Agricultural activities of the land nearby the landfill and practice behavior of workers in the landfill have been observed. Results: We found Salmonella spp. and Clostridium perfringens contaminated in soil samples collected from both inside and outside of landfill. Heavy metals such as Iron (Fe), Magnesium (Mg) and Aluminum (Al) were found in high level, additionally, contamination of Copper (Cu) in soil collected inside the landfill was presented. Water collected from leachate and natural resource was contaminated by coliform bacteria and Salmonella spp. Level of Fe in all water samples was high, however this amount was not above limited value. Inappropriate self-protective and non-hygienic behavior of workers in the landfill was also found. Conclusion: Soil and water samples collected from the opened landfill were contaminated with bacteria. Occupational hazard, protective awareness and protective measure of people who exposed to the landfill such as garbage collectors and farmers should be concerned. Level of heavy metals in soil and water, especially in paddy fields around the landfill should be periodically monitored

Voluntary waste industry protocol for the handling of early collected carbon charges in the landfill sector

The landfill industry, through the Australian Landfill Owners Association and the Australian Local Government Association, has developed this voluntary protocol to ensure that the early collected carbon charges are returned for consumer benefit. Individual landfill owners will have the option to accept to be bound by the protocol. Those who accept shall be identified on the Department of the Environment’s website. The protocol will not override contractual arrangements between landfill operators and their customers. The Minister for the Environment has issued a statement supporting the protocol and calling for wide participation by the landfill industry and other groups in the protocol. The Australian Competition and Consumer Commission (ACCC) has also encouraged landfill industry participants to work with the Government to negotiate an appropriate solution for the handling of early collected carbon charges

Public health and landfill sites

Landfill management is a complex discipline, requiring very high levels of organisation, and considerable investment. Until the early 1990’s most Irish landfill sites were not managed to modern standards. Illegal landfill sites are, of course, usually not managed at all. Landfills are very active. The traditional idea of ‘put it in the ground and forget about it’ is entirely misleading. There is a lot of chemical and biological activity underground. This produces complex changes in the chemistry of the landfill, and of the emissions from the site. The main emissions of concern are landfill gases and contaminated water (which is known as leachate). Both of these emissions have complex and changing chemical compositions, and both depend critically on what has been put into the landfill. The gases spread mainly through the atmosphere, but also through the soil, while the leachate (the water) spreads through surface waters and the local groundwater. Essentially all unmanaged landfills will discharge large volumes of leachate into the local groundwater. In sites where the waste accepted has been properly regulated, and where no hazardous wastes are present, there is a lot known about the likely composition of this leachate and there is some knowledge of its likely biological and health effects. This is not the case for poorly regulated sites, where the composition of the waste accepted is unknown. It is possible to monitor the emissions from landfills, and to reduce some of the adverse health and environmental effects of these. These emissions, and hence the possible health effects, depend greatly on the content of the landfill, and on the details of the local geology and landscape. There is insufficient evidence to demonstrate a clear link between cancers and exposure to landfill, however, it is noted that there may be an association with adverse birth outcomes such as low birth weight and birth defects. It should be noted, however, that modern landfills, run in strict accordance with standard operation procedures, would have much less impact on the health of residents living in proximity to the site

Landfill aeration for emission control before and during landfill mining

The landfill of Modena, in northern Italy, is now crossed by the new high velocity railway line connecting Milan and Bologna. Waste was completely removed from a part of the landfill and a trench for the train line was built. With the aim of facilitating excavation and further disposal of the material extracted, suitable measures were defined. In order to prevent undesired emissions into the excavation area, the aerobic in situ stabilisation by means of the Airflow technology took place before and during the Landfill Mining. Specific project features involved the pneumatic leachate extraction from the aeration wells (to keep the leachate table low inside the landfill and increase the volume of waste available for air migration) and the controlled moisture addition into a limited zone, for a preliminary evaluation of the effects on process enhancement. Waste and leachate were periodically sampled in the landfill during the aeration before the excavation, for quality assessment over time; the evolution of biogas composition in the landfill body and in the extraction system for different plant set-ups during the project was monitored, with specific focus on uncontrolled migration into the excavation area. Waste biological stability significantly increased during the aeration (waste respiration index dropped to 33% of the initial value after six months). Leachate head decreased from 4 to 1.5m; leachate recirculation tests proved the beneficial effects of moisture addition on temperature control, without hampering waste aerobization. Proper management of the aeration plant enabled the minimization of uncontrolled biogas emissions into the excavation area

Risk of low birth weight near EUROHAZCON hazardous waste landfill sites in England.

Few studies have investigated the occurrence of both low birth weight (LBW) and congenital anomalies in populations living near hazardous waste landfill sites. The authors investigated the risk of LBW near 10 English hazardous waste landfill sites included in a previous European study, which reported an increased risk of congenital anomalies. Odds ratios, adjusted for sex, deprivation, year of birth, and study area (pooled ORs), were estimated for LBW (< 2500 gm) within 0-3 km compared with 3-7 km zones around the landfill sites. The authors found a small and not statistically significant increase in risk of LBW (OR = 1.03, 95% confidence interval = 0.98-1.08) within 3 km of hazardous waste landfill sites. Their findings suggest that previously reported results for congenital anomalies should not be extrapolated to a wider range of pregnancy outcomes but should be evaluated separately for each

An Economic Analysis of the Packaging Waste Recovery Note System in the UK

In order to cope with the increasing scarcity of final dump sites for household wastes, the UK recently introduced an environmental policy targeted at the firms that produce and sell products that generate packaging wastes. This policy requires such businesses to hold predetermined numbers of tradable credits called gPackaging waste Recovery Notesh (PRNs). This article provides insights into the economic implications of such a policy through a simple analytical model of a recyclable product and the PRN markets. Our analysis yield two particularly interesting results. First, an increase in the required recycling rate dampens the output and landfill waste levels, while the effect on the level of recycling activities is ambiguous. Second, an increase in the landfill tax always leads to an increase in the landfill waste. We also discuss how the socially optimal landfill tax in the presence of the PRN market should be chosen.PRNs, Recycling, Landfill Tax, Comparative Statics

Sonochemical Degradation of Perfluorooctane Sulfonate (PFOS) and Perfluorooctanoate (PFOA) in Landfill Groundwater: Environmental Matrix Effects

Perfluorinated chemicals such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are environmentally persistent and recalcitrant to most conventional chemical and microbial treatment technologies. In this paper, we show that sonolysis is able to decompose PFOS and PFOA present in groundwater beneath a landfill. However, the pseudo first-order rate constant for the sonochemical degradation in the landfill groundwater is reduced by 61 and 56% relative to MilliQ water for PFOS and PFOA, respectively, primarily due to the presence of other organic constituents. In this study, we evaluate the effect of various organic compounds on the sonochemical decomposition rates of PFOS and PFOA. Organic components in environmental matrices may reduce the sonochemical degradation rates of PFOS and PFOA by competitive adsorption onto the bubble−water interface or by lowering the average interfacial temperatures during transient bubble collapse events. The effect of individual organic compounds depends on the Langmuir adsorption constant, the Henry’s law constant, the specific heat capacity, and the overall endothermic heat of dissociation. Volatile organic compounds (VOCs) are identified as the primary cause of the sonochemical rate reduction for PFOS and PFOA in landfill groundwater, whereas the effect of dissolved natural organic matter (DOM) is not significant. Finally, a combined process of ozonation and sonolysis is shown to substantially recover the rate loss for PFOS and PFOA in landfill groundwater

Are white storks addicted to junk food? Impacts of landfill use on the movement and behaviour of resident white storks (Ciconia ciconia) from a partially migratory population

Background: The migratory patterns of animals are changing in response to global environmental change with many species forming resident populations in areas where they were once migratory. The white stork (Ciconia ciconia) was wholly migratory in Europe but recently guaranteed, year-round food from landfill sites has facilitated the establishment of resident populations in Iberia. In this study 17 resident white storks were fitted with GPS/GSM data loggers (including accelerometer) and tracked for 9.1 ± 3.7 months to quantify the extent and consistency of landfill attendance by individuals during the non-breeding and breeding seasons and to assess the influence of landfill use on daily distances travelled, percentage of GPS fixes spent foraging and non-landfill foraging ranges. Results: Resident white storks used landfill more during non-breeding (20.1 % ± 2.3 of foraging GPS fixes) than during breeding (14.9 % ± 2.2). Landfill attendance declined with increasing distance between nest and landfill in both seasons. During non-breeding a large percentage of GPS fixes occurred on the nest throughout the day (27 % ± 3.0 of fixes) in the majority of tagged storks. This study provides first confirmation of year-round nest use by resident white storks. The percentage of GPS fixes on the nest was not influenced by the distance between nest and the landfill site. Storks travelled up to 48.2 km to visit landfills during non-breeding and a maximum of 28.1 km during breeding, notably further than previous estimates. Storks nesting close to landfill sites used landfill more and had smaller foraging ranges in non-landfill habitat indicating higher reliance on landfill. The majority of non-landfill foraging occurred around the nest and long distance trips were made specifically to visit landfill. Conclusions: The continuous availability of food resources on landfill has facilitated year-round nest use in white storks and is influencing their home ranges and movement behaviour. White storks rely on landfill sites for foraging especially during the non-breeding season when other food resources are scarcer and this artificial food supplementation probably facilitated the establishment of resident populations. The closure of landfills, as required by EU Landfill Directives, will likely cause dramatic impacts on white stork populations

Measurement of representative landfill gas migration samples at landfill perimeters: a case study

This paper describes the development of a fully integrated autonomous system based on existing infrared sensing technology capable of monitoring landfill gas migration (specifically carbon dioxide and methane) at landfill sites. Sampling using the described system was validated against the industry standard, GA2000 Plus hand held device, manufactured by Geotechnical Instruments Inc. As a consequence of repeated sampling during validation experiments, fluctuations in the gas mixtures became apparent. This initiated a parallel study into what constitutes a representative sample of landfill gas migration as reported to the Environmental Protection Agency. The work described in this paper shows that gas mixture concentrations change with depth of extraction from the borehole well, but with evidence of a steady state after a time