Each year a large number of wooden pallets are manufactured, recycled, and disposed of during the transportation of goods throughout the United States. The production of these pallets consumes a significant amount of wood and a large number of pallets also end up in landfills at the end of their useful life cycle. However, these pallets can be recovered through repair, broken apart into components, ground into mulch, fuel, animal bedding, or used by landfills for day to day operations. The purpose of this research was to investigate the total number of pallets and crates reaching landfills in the United States as well as to gain a better understanding of the overall waste stream. This was done by surveying all licensed Municipal Solid Waste (MSW) and Construction and Demolition (CandD) landfills in the continental United States. A questionnaire was sent to these landfills, and this entire study was intended to build upon previous Virginia Tech landfill surveys conducted in 1995 and 1998 with some changes made after careful review. Overall, it was found the average MSW facility in the United States received 185,077 tons of waste and the average CandD facility received 74,911 tons. This results in a total national estimate of 253 million tons of MSW and 76.9 million tons of CandD waste. Approximately 18.3 million pallets were landfilled and an additional 13.8 million were recovered, repurposed, or reused at MSW facilities. At CandD facilities, approximately 19.2 million pallets were landfilled while 38.3 million were recovered. / Master of Science / Millions of wooden pallets are involved in the transportation of goods each year and have a major role in the global distribution system. The production of these pallets consumes large volumes of wood that may end up in landfills when their life cycles have been completed. Generally, wood is a desirable natural resource and landfilling is the least desirable method of waste management. However, pallets can be recovered through repair, broken apart into components, or ground into mulch, fuel, animal bedding, or used by landfills for day to day operations. The purpose of this research was to investigate the total number of pallets and crates reaching pallets in the United States as well as to gain a better understanding of the overall waste stream. This was done by surveying over 2500 licensed Municipal Solid Waste (MSW) and Construction & Demolition (C&D) landfills in the continental United States through mail questionnaire with an option to be completed online. Overall, it was found the average MSW facility in the United States received 185,077 tons of waste per year and the average C&D facility received 74,911 tons. This results in a total national estimate of 253 million tons of MSW and 76.9 million tons of C&D waste. Approximately 18.3 million pallets were landfilled and an additional 13.8 million were recovered, repurposed, or reused at MSW facilities. At C&D facilities, approximately 19.2 million pallets were landfilled while 38.3 million were recovered. This represents a decrease in the number of pallets landfilled and an increase in the number recovered when compared to the surveys conducted in 1995 and 1998 by Corr et al.

Orientador: Orlando Luis Goulart Peres. / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin. / Made available in DSpace on 2018-08-12T10:38:02Z (GMT). No. of bitstreams: 1 BastoGonzalez_VictorSaul_M.pdf: 1541009 bytes, checksum: b798dea659147d5050c68800d40ceb0a (MD5) Previous issue date: 2008 / Resumo: Com este trabalho buscamos entender o fenômeno de oscilações de neutrinos na matéria. Para isto, estudamos a propagação de neutrinos em Supernovas. O estudo é feito nestes objetos astrofísicos, pois são produzidos neutrinos de todos os sabores quando a estrela progenitor da Supernova é muito massiva. Além de isto, estes corpos celestes atingem densidades muito maiores que a densidade solar. Uma razão adicional muito importante é que os neutrinos são mensageiros ideais e poderão ser observados antes mesmo da observação óptica da explosão de Supernova, assim eles podem fornecer informação sobre os processo que levam à formação de Supernova. Para fazer esse estudo consideramos os valores atuais dos parâmetros de oscilações de neutrinos e um perfil de densidade para a matéria da estrela moribunda. Encontramos que os neutrinos experimentam o efeito Mikheyev-Smirnov-Wolfenstein (MSW) em dois regimes de densidades diferentes. A existência destas regiões dependerá da hierarquia nas massas dos neutrinos e se é partícula/antipartícula. Encontramos que para no caso de antineutrinos eletrônicos o fluxo na Terra dependerá do tipo de hierarquia e do valor do ângulo de mistura q13, esse ângulo de mistura modificará o tipo de transição pela zona de ressonância de densidades altas na Supernova. Encontramos que o número de eventos, para esses antineutrinos, è diferente se a hierarquia na massa é normal ou invertida. A diferença é mais notória se a luminosidade em neutrinos não está equipartida. Também encontramos que o número de eventos no detector Super-Kamiokande dependerá do tipo de propagação na região mais interna de Supernova para hierarquia invertida e caso q 13 10-3 , podemos ter informação sobre esses ângulo de mistura caso conseguiremos diferenciar o espectro sem oscilação e com oscilação induzido por efeito puramente adiabático. Neste estudo não tivemos em conta o efeito da matéria na Terra. / Abstract: In this work we study the behaviour of the neutrino oscillations in the matter. To do so, we studied the propagation of neutrinos in Supernovae. The study is done on this astrophysical objects because there are produced all avor of neutrinos when the Supernova progenitor star is very massive. Moreover, this celestial bodies reach much higher densities than the solar density. An additional and very important reason to study neutrinos in Supernova is because neutrinos are ideal messengers, thus they could be detected even before of the optical observation of the Supernova explosion. We considered the updated oscillation parameter values for neutrinos and a density profile of the matter in the dying star. Also, we consider that in the neutrino propagation in a medium it is modified by the medium density, being known as Mikheyev-Smirnov-Wolfenstein (MSW) effect. The existence of regions in which the MSW effect is very relevant will depend on the mass hierarchy of the neutrinos/antineutrinos and if they are neutrinos or antineutrinos. We found in the case of anti electron neutrinos that the ux in the Earth will depend on the type of hierarchy and on the value of the mixing angle q 13, that angle will modify the kind of transition in the resonance zone in the regime of high densities in the Supernova. We calculated the number of events for those antineutrinos and we have found that the value depend if the mass hierarchy is normal or inverted. The difference is even more evident if the total luminosity of the neutrinos is not equally distributed between the all neutrino avors. Finally, we also found that the number of events in the Super-Kamiokande detector will depend on the propagation in the Supernova inner region for the inverted hierarchy and when the mixture angle q 13 10-3. In this study we will not consider the Earth¿s matter effect. / Mestrado / Física das Particulas Elementares e Campos / Mestre em Física

A relatively new concept of Municipal Solid Waste treatment is known as bioreactor landfill technology. Bioreactor landfills are sanitary landfills that use microbiological processes purposefully to transform and stabilize the biodegradable organic waste constituents in a shorter period of time. One of the most popular types of bioreactor landfills is the landfill with leachate recirculation. However, it is observed that ammonia rapidly accumulates in landfills that recirculate leachate and may be the component that limits the potential to discharge excess leachate to the environment. In the facultative landfill, leachate is nitrified biologically using an on-site treatment plant and converted by denitrifying bacteria to nitrogen gas, a harmless end-product. In this research, three pilot-plant scale lysimeters are used in a comparative evaluation of the effect of recirculating treated and untreated leachate on waste stabilization rates. The three lysimeters are filled with waste prepared with identical composition. One is being operated as a facultative bioreactor landfill with external leachate pre-treatment prior to recirculation, the second is being operated as an anaerobic bioreactor landfill with straight raw leachate recirculation, and the third one is the control unit and operated as a conventional landfill. Apart from environmental restrictions, geotechnical constraints are also imposed on new sanitary landfills. The scarcity of new potential disposal areas imposes higher and higher landfills, in order to utilize the maximum capacity ofthose areas. In this context, the knowledge of the compressibility of waste landfills represents a powerful tool to search for alternatives for optimization of disposal areas and new solid waste disposal technologies. This dissertation deals with and discusses the environmental and geotechnical aspects of municipal solid waste landfills. In the Environmental Engineering area, it compares the quality of the leachate and gas generated in the three lysimeters and discusses the transfer of the technology studied through lysimeters to procedures for full-scale operation. In the geotechnical area, this dissertation discusses the compressibility properties of the waste and provides a state-of-the-art review of MSW compressibility studies. It also evaluates the compressibility of MSW landfills for immediate and long-term settlements and proposes a new model for compressibility of waste landfills.

In USA, the Municipal Solid Waste (MSW) landfills accumulate about 130 million tons of solid waste every year. A significant amount of biodegradable solid waste is converted to landfill gas due to anaerobic stabilization by bacteria. These biochemical reactions produce volatile organic compounds (VOCs) like methane and others. Due to heterogeneity in refuse composition, unpredictable distribution of favorable environmental conditions for bacterial actions and highly uncertain pathway of gases, estimation of landfill gas emission for a particular landfill is complex. However, it is important to quantify landfill gases for health risk assessment and energy recovery purposes. This research is based on the monitoring and modeling methodology proposed by researchers at University of Central Florida is reported in this thesis. River Birch Sub-title D landfill, Westwego, LA was selected as the study area. The total emission calculated using the mathematical model ran on MATLAB is comparable with the result obtained from EPA LandGEM model, using historical waste deposition records

The purpose of this study was to explore healthy and maladaptive coping strategies among MSW students. The data was collected using self‑reported questionnaires. A total of 47 students participated in this study. Using the Transactional Model of Stress and Coping as a theoretical framework, this study assessed stress levels using the Perceived Stress Scale. The Brief COPE instrument measured coping strategies. The study found relationships between stressors and maladaptive coping and perceived stress. The study recommends that future research on coping strategies among MSW students include greater attention to training MSW students how to deal with stress during their MSW educational programs.

This study utilized a quantitative survey design in order to explore the perceptions and preparedness of Master of Social Work (MSW) students in regards to substance using clients. The study was exploratory and the data that was collected focused on the perceptions, attitudes, and level of preparedness of forty MSW students. The study used a self-report survey that included demographic questions in order to identify factors such as age, gender, ethnicity, cohort placement, current year in the program, formal training, and declared specialization. This study found that the perceptions and attitudes of MSW students were mixed and varied across the board. Results indicated that formal training contributed to level of preparedness and that a large majority of the sample felt that taking a substance use course would contribute to preparedness. The study also found that the majority of the sample felt that their MSW program did not contribute to preparedness. The study recommends that future studies on perceptions and preparedness of MSW students collect data from more than one MSW program and include qualitative interviews in order to gain a better understanding of MSW students’ perceptions.

The purpose of this study was to examine trends in MSW graduate student's self-reported levels of healthy habits, family support and relationships during education, self-care, personal standards, as well as time management, and what the implications of those things are related to student burnout. The hypothesis was that students are burned out before they enter the social work field professionally. This poses a problem because the social work field has an already high level of burnout, turnover, and compassion fatigue. This study examines the trends in both the online pathways program and the on-the- ground ground program.

Social workers are being sought out more often to treat traumatized individuals. In turn, social workers are at risk of vicarious traumatization. Vicarious trauma is a form of indirect trauma that may occur by working with traumatized clients. Master of Social Work (MSW) students should be educated on vicarious trauma as they will have many responsibilities when they begin their work in the field; including treating traumatized individuals. Education on vicarious trauma could lessen the risks of experiencing the pathology. The purpose of this study is to explore the perception of vicarious trauma among MSW students. Sixty-seven students from the MSW program at California State University, San Bernardino participated in this study and completed the Vicarious Trauma Questionnaire (VTQ). The study showed that on average the students scored moderate to low on each category of the questionnaire. Suggestions for future research and the social work curriculum are discussed in this project.

Production of biogas through anaerobic digestion (AD) from the organic fraction of minucipal solid waste (OFMSW) was compared to incineration of the waste. At the moment, almost all of the OFMSW in Singapore is incinerated. Three different scales of biogas plants were compared to incineration: one large-scale biogas plant that can treat half of all OFMSW in Singapore; one medium- scale biogas plant about 15 times smaller than the large one; and one small-scale biogas plant that can treat waste from e.g. a shopping centre or food centre. Two alternatives for utilization of the biogas were also compared, generation of electricity and the use of the biogas in heavy vehicles. The combination of the different scales and the different utilization gives the six different scenarios. By using life cycle assessment (LCA) the different scenarios were compared in terms of global warming potential (GWP), acidification, eutrophication, energy use and land use. The results show that biogas production creates less environmental impact than incineration. The use of the gas as a vehicle fuel creates a bigger decrease of GWP, acidification and eutrophication than when using the gas for electricity generation. The prevention of leakage of biogas during production and upgrading is crucial for the environmental impact on GWP. A leakage of only a few percent of the produced gas will lead to a loss of all the gain in saved GHG-emissions.

Several catastrophic failures have occurred during the past two decades, both in engineered as well as non-engineered landfills. In addition, there are numerous instances of significant deformations, although not failure in the sense of significant and rapid downslope mass movement, which may cause sufficient damage to buried gas and leachate collection infrastructure. One such instance was observed in 1999 near the toe of a 75 m high 4H:1V slope at the Brock West Landfill in Ontario, Canada. Significant distortion of gas collection laterals was observed at this site. The present research is an in-depth study intended to examine deformation in landfills based on a detailed study of the mechanical properties of municipal solid waste. Four research objectives were defined based on identified shortcomings and knowledge gaps in the existing literature pertaining to mechanical properties of MSW viz; (a) to develop a method for obtaining intact samples of MSW and to examine the significance of using intact and recompacted samples in characterizing the stress-deformation behaviour of MSW; (b) to characterize MSW shear strength and Youngs modulus of elasticity from interpretation of triaxial test results and to determine the parameters of a non-linear elastic constitutive model as applied to MSW; (c) to measure the evolution of compressibility behaviour of MSW with degradation and verify the mechanism of secondary compression in waste; (d) to develop a simple design chart for predicting lateral deformations in landfills. A comprehensive research program was carried out to address various research objectives - field monitoring of deformations at the Brock West site; triaxial compression tests on large intact and recompacted samples of waste; simulating waste degradation in a large laboratory compression cell; analyzing stress-strain data from various published studies and a numerical modelling study. Interpretation of the effective stress paths followed during shearing in triaxial compression tests suggested that while recompacted samples may be sufficient to characterize shear strength parameters for use in stability analysis of landfill slopes, there might be a benefit in obtaining intact samples to evaluate the deformation characteristics of MSW. A hyperbolic model is proposed to describe the stress-deformation response of waste. The required parameters for this model were determined from evaluation of the results of numerous triaxial tests, both from this study and from the published literature. Observations from the long-term degradation test suggested that degradation has a significant effect on the compressibility of waste and further verifies the mechanism of secondary compression in waste. The coefficient of at-rest lateral pressure was observed to maintain an essentially constant value during combined compression and degradation.<p>The results obtained from the experimental work were combined with the findings of a stochastic numerical modelling study and a statistical evaluation of published data and used to propose a simple design chart for estimating the maximum lateral displacement in a landfill slope. The design chart was developed using results of a finite element parametric study in which the behaviour of the municipal solid waste was modeled using a non-linear elastic hyperbolic model. The design chart incorporates nonlinear variation in unit weight as well as Youngs modulus with depth. The predictions from the design chart were compared with the results of field monitoring of lateral displacement in the instrumented slope at the Brock West landfill and were found to be in good agreement.