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Pilot-Scale In Situ Treatment of a Chlorinated Hydrocarbons Contaminated Site by Combined Technologies of Electrokinetic Processing-Fenton Process ¡V Catalytic Iron WallChun, Hung-Yuan 27 August 2002 (has links)
This research was to evaluate the treatment efficiency of a chlorinated hydrocarbons contaminated site by combined technologies of electrokinetic processing-Fenton process-catalytic iron wall. The L9 orthogonal arrays were utilized to investigate the effects of four experimental factors (i.e., H2O2 concentration, size fraction of iron particles, mass of iron particles and elapsed time) on the treatment efficiency. The experimental results were further subjected to the analysis of variance (ANOVA) and regular analysis. According to the ANOVA of results of nine experiments conducted under an electric gradient of 1 V/cm, the H2O2 concentration, mass of iron particles and elapsed time were determined to be very significant parameters for the destruction and removal efficiency (DRE) of 1,1,2,2-tetrachloroethane (TeCA) . In this system, the optimal conditions with respect to the DRE of TeCA would be 2¢MH2O2, 50-100 mesh iron, 0.2 wt% iron and 20-day treatment time. Under this optimal conditions, it was able to obtain a DRE of 69.56% and the corresponding operating cost would be 672.9 NT$/m3.
Aside from the constant voltage operation, the constant current operation also was employed in this study. The latter was found to be superior to the former in terms of electroosmotic flow quantity and DRE.
Experimental results of soil column tests showed that TeCA was transformed to trichloroethylene (TCE). TCE could be regarded as a daughter product of TeCA degradation. Results of Tests 17 and 18 showed that destruction dominated the DRE of TeCA, whereas removal played a much more important role in the DRE of Test 19. Regarding the treatment efficiency of a 9-day pilot test using the same combined treatment technologies, it was found to be very satisfactory. DREs of vinyl chloride, dichloroethane, and TCE were found to be >96%, >96%, and >94%, respectively in the anode and cathode wells. The concentrations of TCE in both anode and cathode wells were found to be lower than the regulatory threshold (i.e., 2£gg/L) and the operating cost was determined to be about NT$57.5/m3.
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The legacy of urbanization: historical land use and its impact on current health hazards at a community garden in Charlestown, MassachusettsKim, Baram January 2013 (has links)
INTRODUCTION: The Charlestown Sprouts Community Garden, one of Bostonʼs largest community gardens, comprises 105 plots--all producing food--located in the historic neighborhood of Charlestown. It serves mainly minority and recent immigrant member households who rely on the land as a source of fresh produce. To ensure the safety of food production at the garden, the coordinators sought assistance from the Department of Environmental Health at the Boston University School of Public Health (BUSPH) to: 1. conduct a historical survey identifying past land uses, 2. characterize potential contaminant exposures to gardeners, and 3. furnish health-protective recommendations to minimize gardener hazard exposures. In the process of meeting these aims, broader dimensions of food production in the urban environment emerged from the literature: soil safety for urban agriculture, environmental justice, food security, determining “safe”
levels of contaminants in urban soil, and the expansive policy implications that these issues engendered. For the work presented in this thesis project, the scope of interrelated topics were refined and lended contextual structure for a semi-quantitative characterization of human health risk from potential soil lead (Pb) exposures. This was accomplished by employing probabilistic modeling with the USEPA's Integrated Exposure Uptake Biokinetic Model for Lead in Children (IEUBK) (2010). Under specified assumptions of multimedia Pb exposures, the model predicts a
theoretical young childʼs probability of his or her lead blood concentrationʼs (PbB) exceeding a PbB cutoff. For this analysis, the recently promulgated CDC reference value of 5 μg/dL was used as a cutoff in addition to the model default of 10 μg/dL. The IEUBK was also employed to approximate a range of soil Pb concentrations that could be considered “acceptable,” based on a health-protective approach; that is, to estimate a soil Pb concentration that would not significantly contribute to the exceedance of PbB > 5 μg/dL as a result of exposures to lead in soil. In this evaluation, an acceptable soil Pb concentration is defined as a mean soil Pb concentration that is determined by consideration of minimizing human health risk and maximizing practicability of the
means to achieve the soil criterion—a level that could be reasonably achieved and be
safe for urban agriculture.
METHODS: Research for the historical survey included, but was not limited to, consulting historical fire insurance maps, archived municipal and county records, environmental databases, geographic information systems (GIS), and gathering accounts from local community members, historical societies, and multiple Boston city agencies to build a historical narrative about the garden land and the adjacent properties. For the IEUBK model runs, multimedia exposure parameter values from Boston environmental data (air, water, and soil) were used as inputs for the IEUBK modeling
runs in the absence of suitable site-specific data. Comparison runs were executed with soil Pb concentration data from compost sourced from the City of Boston Department of Public Works Leaf and Yard Waste composting program and from Boston-area private compost facilities.
RESULTS AND CONCLUSIONS: The garden was established at a site with a varied history of
land uses from rail yard, to salt plant, to unknown activities. Community-member accounts, corroborated by photointerpretation data, suggest that the site was possibly an dumping grounds in the 1970ʼs-80ʼs. Based on the findings of the survey, it is likely that a number of potential contaminants exist at the garden, including lead, arsenic and/or polyaromatic hydrocarbons (PAHs). Based on visual inspection, point-source contamination of the soil is likely to be occurring at the garden, stemming from the treated rail ties that compose a majority of the garden plot constructions and of the plots inspected, the timbers appeared to be CCA-treated wood. The accumulation of site-specific knowledge gained through historical research, (GIS), and anecdotal evidence aided in determining what historical hazards were likely to pose a current risk to gardeners through gardening activities.
The IEUBK model predicted a geometric mean blood value of 2.73 μg/dL with an associated risk of a young childʼs PbB exceeding 5 ug/dL as 9.9% using default parameter values. In comparison, to achieve a goal of less than 5% risk, the IEUBK modeling indicated that soil Pb would have to be less than 153 mg/kg. Under the guidance of BUSPH faculty, the findings and consequent recommendations, differing in remediation technique and resource-intensiveness, were summarized in a document for the garden steering committeeʼs development of imminent renovation plans.
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Phosphate reclamation from water using Douglas fir biochar Fe/Mg-LDH CompositesRahman, Sharifur 07 August 2020 (has links)
Eutrophication, caused by phosphate, can be detrimental both for the aquatic environment and human health. This research aims to provide deep knowledge about the adsorption properties of low-cost Fe/Mg layered double hydroxide modified biochar (LDHBC) for removal of phosphate from aqueous solution. Firstly, Fe/Mg layered double hydroxide (LDH) was synthesized by mixing FeCl3 and MgCl2. 6H2O salts in water, followed by NaOH treatment (coprecipitation method). For LDHBC, FeCl3, and MgCl2. 6H2O salts were dissolved in water, and Douglas fir biochar was added to the salts mixture to make a slurry, followed by NaOH treatment. The surface chemistry and elemental composition of both adsorbents and phosphate-laden adsorbents were characterized using Elemental analysis, BET, PZC, TGA, DSC, XRD, SEM, and TEM. Adsorption ability of LDH and LDHBC was studied by pH effects, kinetics, and the highest capacity for the analyte.
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Determining and meeting the educational needs of students and urban gardeners and farmers on urban soil quality and contamination topicsHarms, Ashley Marie Raes January 1900 (has links)
Master of Science / Department of Agronomy / DeAnn Presley / Steve Thien / Interest and participation in urban agriculture is growing in many cities throughout the United States. Urban gardeners and farmers produce food on various types of urban lands. Common soil contaminants of urban areas limit the amount of land on which food may safely be grown. The objective of this study was to assess and meet the informational and technical assistance needs of urban gardeners and farmers as well as students enrolled in the introductory soils science course at Kansas State University on the topics of urban soil quality and contamination. A needs assessment survey of urban gardeners and farmers was conducted in four communities; Tacoma and Seattle, Washington, Kansas City, Kansas and Missouri, Manhattan, Kansas, and Gary, Indiana. The survey generated information about what urban gardeners and farmers know, think they know, and want to know about urban soil quality and contamination. Eighty-eight percent of respondents indicated that they do not have knowledge of the best management practices to minimize health risks involved when growing food crops on soils contaminated with lead, cadmium, arsenic or organic contaminants. Our results suggest that urban gardeners and farmers require and want information and guidance on soil testing for common contaminants, interpretation of testing results, and best management practices for growing food on mildly contaminated soils. The students enrolled in the introductory soil science course at Kansas State University are future agricultural and environmental professionals who need skills to address urban soils issues. Most of the students in the Agronomy 305: Soils course are not Agronomy majors. Furthermore, an increasing number of Agronomy 305 students come from urban and suburban communities and/or have interest in working in urban environments upon completion of their undergraduate degree. An urban soils laboratory was developed in response to the future workforce demands as well as the demographics of students enrolled in the Agronomy 305 course. Throughout the semester students evaluated the physical, chemical, and biological properties of a soil from this urban community garden. Reaction of students to the new urban soils lab offering has been positive with 72% of students enrolled in the course reporting that they have interest and need in learning about the urban soil issues covered in the lab course. Overall, student responses about their learning experience in the urban soils laboratory course were positive, indicating that incorporating urban soil principles enhanced their soil science education. Students who participated in the urban soils lab are better prepared, as future agricultural and environmental professionals, to address the educational and technical assistance needs of urban growers.
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Immunotoxicity of Chromium Contaminated Soil in the Earthworm, Lumbricus TerrestrisMohammadian, Gholamreza 05 1900 (has links)
Objective was to assess the toxicity of chromium (Cr) contaminated soil (CS) using the earthworm Lumbricus terrestris. Specific aims were to determine: (1) survival (LC50); .(2) immunotoxicity as indicated by lysozyme activity, coelomocyte counts, secretory (SR) and erythrocyte rosette (ER) formation, and phagocytosis; and (3) compare effects of CS exposure with those of Cr spiked artificial soil (AS) . CS Cr concentration was 8.78 mg/g with 98.2% being Cr^3+ and 1.8% being Cr^6+. Using 14 d AS protocol the LC50 was 6.49% CS: AS mixture. CS concentrations of 0.5, 1.0, 2.5 and 5.0% were sublethal, whereas 6.25, 12.5, 25, 50 and 100% CS were lethal. Sublethal exposure caused no immuno- modulation. Exposure to 50% CS: AS mixture for 5 d caused reduced SR and ER formation. Exposure to AS spiked with 0.27% Cr for 5 d resulted in immunomodulation equivalent to 50% CS: AS mixtures. Results indicated the CS to be acutely toxic.
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Estudo da resposta IP de solos argilosos contaminados por hidrocarbonetos e chorume / A study on the IP response from clayey soils contaminated by hydrocarbons and inorganic co mpounds.Ustra, Andréa Teixeira 28 June 2013 (has links)
A tese de doutoramento apresenta uma pesquisa que teve como objetivo principal estudar a resposta IP gerada pela contaminação de solos argilosos por compostos orgânicos e inorgânicos. Ensaios de campo e laboratório foram realizados para investigar a sensibilidade do método IP à mudanças na propriedades petrofísicas provocadas pela contaminação. Um experimento controlado investigou o efeito IP gerado em amostras coletadas em torno de um aterro de resíduos urbanos, saturadas por diferentes concentrações de chorume, coletado no próprio local. Os resultados mostram um aumento do efeito IP em amostras ricas em CaCO3, observado mesmo para altas concentrações de chorume. Um segundo experimento controlado investigou o efeito do teor e tipo de argila e da salinidade na resposta IP. Misturas de esferas de vidro e diferentes teores de caulinita e montmorilonita foram saturadas por soluções de diferentes concentrações de NaCl. Os resultados obtidos mostram que o efeito da concentração de sais na resposta IP depende do teor de tipo de argila, sendo esse último dominante em relação ao efeito da salinidade. A concentração de sais e o teor de argila atuam de forma acoplada, intensificando o efeito IP. Em um terceiro experimento, a sensibilidade da resposta IP a presença de tolueno foi investigada. Misturas de areia e montmorilonita foram artificialmente contaminadas por diferentes concentrações de tolueno. Os resultados desse experimento mostram que o efeito desse contaminante na resposta IP é pequeno. Ainda assim, foi possível observar uma dependência da resposta IP com a concentração de tolueno que muda com o tempo, provavelmente devido a mudanças interfaciais químicas após a adição de tolueno. Com o objetivo de estudar o efeito da biodegradação do tolueno em solos argilosos na resposta IP gerada, duas colunas compostas de uma mistura de areia e caulinita, artificialmente contaminadas por tolueno, foram preparadas. Um fluxo de água subterrânea coletada em uma área contaminada foi estabelecido em uma das colunas (ativa), enquanto que uma solução de água deoneizada e NaCl foi estabelecido na outra (controle). A resposta IP das duas colunas foi monitorada por um período de quatro meses e nenhuma mudança na resposta elétrica das colunas que indicasse a ocorrência de biodegradação do tolueno foi observada. Os dados geoquímicos comprovam que não houve mudanças significativas durante o período do monitoramento, mesmo embora a presença de bactérias anaeróbicas vivas tenha sido verificada tanto na solução de entrada como na solução de saída da coluna ativa. Uma possível explicação para o tolueno não ter sido biodegradado de forma eficiente é a sua alta concentração na colunas. O último estudo realizado consiste na utilização do método IP para a investigação de uma área contaminada por BTEX (benzeno, tolueno, etil-benzeno e xileno). A contaminação ocorreu devido a derrames acidentais de quantidade não estimada de solventes no solo não impermeabilizado. O ensaio de campo revela uma zona de anomalia, caracterizada por baixas resistividade e cargabilidade e aumento da cargabilidade normalizada. Amostras de solo foram coletadas na área e tiveram suas propriedades elétricas medidas em laboratório. O contraste elétrico observado em campo não foi observado em laboratório, sugerindo que variações do teor de umidade podem estar contribuindo para a anomalia geofísica observada em campo. O teor de argila, bactérias totais e propriedades magnéticas foram medidas em diversas amostras coletadas na área. Os resultados dessas análises mostram que a distribuição do teor de argila não explica a anomalia observada. Entretanto, a população microbiana encontrada foi cinco ordens de magnitude maior na zona de anomalia. As propriedades magnéticas mostram que as amostras coletadas na zona da anomalia são mais ricas em magnetita. Os estudos realizados nessa pesquisa mostram que a resposta IP observada em estudos ambientais é afetada por propriedades petrofísicas como o teor de argila, teor de umidade, mineralogia e propriedades químicas do fluido dos poros. Entretanto a variação natural dessas propriedades também é esperada em ambientes dinâmicos. Consequentemente, isolar a contribuição de mudanças dessas propriedades devido a contaminação é uma tarefa complexa. / This PhD Thesis presents a research that aimed to study the IP response from soils contaminated by organic and inorganic compounds. Field surveys and laboratory experiments were conducted to investigate the sensibility of the IP method to changes in petrophysical properties due to contamination. A controlled experiment investigated the IP effect generated in soil samples collected around an urban waste disposal site, saturated by the leacheate generated at the site. The results show an IP effect increase on samples rich in CaCO3, observed even for high contaminant concentrations in the saturation solution. A second experiment investigated the effect of clay type and content and salinity on the IP response. Glass beads with varying concentration of kaolin and bentonite mixtures were synthesized and saturated by solutions with varying salt concentration. The results of this experiment show that the effect of salinity on the IP response depends upon clay type and content, being the clay effect dominant over the salinity effect. The effects of ionic concentration and clay content on the IP effect are coupled, enhancing the IP response. In a third experiment, the IP sensibility to toluene contamination is investigated. Sand and montmorillonite mixtures were artificially contaminated with varying toluene concentrations. The results show that the toluene effect on the IP response is small. Even though, there is an IP response dependency on toluene concentration that changes with time, probably due to interfacial chemical properties changes after the addition of toluene. With the purpose of studying the effect of toluene biodegradation on the IP response, two columns were packed with a sand and kaolinite mixture, artificially contaminated with toluene. A contaminated groundwater solution flux was established in one column (active), and a NaCl and deoneized water solution flux was established on the other column (control). The IP response from both columns was monitored for a period of four months. No significant changes in the electrical properties of these columns that could indicate toluene biodegradation was observed. Geochemical data confirmed that no significant changes occurred during the monitoring period, even though live anaerobic microorganisms were verified in the active column inflow and outflow. One possible explanation for the inefficiency in degrading toluene is its high concentration in the columns. The last study presented is a BTEX (benzene, toluene, ethyl benzene and xylene) contaminated area investigated with the IP method. The contamination events took place due to accidental spills directly into the soil, where the exact amount of contaminant disposed is unknown. The geophysical survey revealed an IP response anomaly, characterized by low resistivities and chargeabilities and normalized chargeability enhancement. Soil samples were collected at the site and its electrical properties were measured in the laboratory. The electrical contrast observed in the field was not observed in the laboratory, suggesting that moisture content could be contributing to the geophysical anomaly observed at the field. Clay content, total bacteria and magnetic properties were measured for some of the collected samples. The results show that the clay content distribution in the area does not explain the geophysical response observed. However, the microbial population was found to be over five orders of magnitude higher in the anomaly zone. Magnetic properties of the samples show that the anomaly zone is richer in magnetite. These studies show that the IP response observed in environmental studies is affected by petrophysical properties such as clay content, moisture content, mineralogy and pore fluid chemical properties. However, natural changes of these properties are also expected in dynamic environments. The isolation of the contribution of soil contamination to changes of these properties is a complex task.
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Estudo da utilização de composto orgânico para a remediação de solo contaminado por hidrocarbonetos de petróleo / Study of the use of compost for the remediation of a petroleum hydrocarbons contaminated soilGuimarães, Camila Camolesi 14 September 2018 (has links)
O Estado de São Paulo apresenta, atualmente, mais de 5.900 áreas contaminadas cadastradas, as quais foram ou devem ser submetidas a um processo de remediação. Os principais contaminantes identificados são os combustíveis automotivos, com destaque para os hidrocarbonetos derivados de petróleo. Dentre as técnicas de remediação existentes, e considerando-se a necessidade de inclusão dos princípios da sustentabilidade aos processos de remediação, destaca-se a estratégia de adição de composto orgânico ao solo contaminado. O composto apresenta grande potencial de biorremediação, pois é capaz de sustentar e promover o crescimento de diversas populações de microrganismos com habilidade de degradar uma série de contaminantes. Nota-se, no Brasil, grande potencial de utilização de composto para a remediação, tanto pelas características climáticas e físico-químicas dos solos quanto pela quantidade de resíduos orgânicos gerados no país. Dessa forma, a presente dissertação tem por objetivo estudar a aplicação de composto orgânico na remediação de solo contaminado por hidrocarbonetos derivados de petróleo, em escala laboratorial. Foi realizada a contaminação artificial de um solo argiloso com óleo diesel e uma mistura de óleo BPF, diesel e querosene, em duas concentrações (10 g/kg e 100 g/kg) e adicionado composto orgânico em duas proporções (1:0,1 e 1:0,5). Os resultados indicaram maiores reduções das concentrações de hidrocarbonetos totais de petróleo ao final do experimento para os tratamentos realizados com óleo diesel, da ordem de 60 % a quase 90 % no período de 91 dias. A presença do composto contribuiu para o aumento dos teores de matéria orgânica, sólidos voláteis, pH e condutividade elétrica dos tratamentos, além da melhoria da estrutura do solo e maior desenvolvimento de populações de microrganismos. Dessa forma, o composto atuou como fonte de energia para os microrganismos autóctones de solo e como fonte de novos microrganismos metabolicamente ativos, contribuindo para o aumento das taxas de biodegradação. Os resultados do presente trabalho indicam que a adição de composto se mostra eficaz na remediação de solos contaminados por hidrocarbonetos de petróleo, promovendo a melhoria das condições físicas, químicas e biológicos do solo e apresentando-se como uma técnica sustentável, com impactos positivos dos pontos de vista ambiental, social e econômico. / The State of São Paulo currently has more than 5,900 registered contaminated sites, which were or have to be submitted to a remediation process. The main contaminants identified are automotive fuels, with emphasis on petroleum-derived hydrocarbons. Among the existent remediation techniques, and considering the need to include sustainability principles to remediation processes, the strategy of adding organic compost to the contaminated soil stands out. The compost presents a great bioremediation potential as it is capable of sustaining and promoting the growth of diverse microorganisms populations, with potential to degrade a series of contaminants. In Brazil, there are great opportunities for the use of compost for the remediation of contaminated soils, both due to the climatic and physical-chemical characteristics of the soils and the amount of organic waste generated in the country. Thus, the present research aims to study the application of compost in the remediation of a hydrocarbon contaminated soil, in laboratory scale. It was performed the artificial contamination of a clay soil with diesel oil and a mixture of bunker oil, diesel and kerosene in two concentrations (10 g/kg and 100 g/kg) and the compost was added in two proportions (1:0.1 and 1:0.5). The results showed greater reductions in the concentrations of total petroleum hydrocarbons at the end of the experiment for treatments with diesel oil, ranging from 60% to almost 90% in a period of 91 days. The presence of compost contributed to an increase in the contents of organic matter and volatile solids, as well as in the values of pH and electrical conductivity. It was also observed an improvement of the soil structure and a greater development of microbial populations. Thus, the compost acted as an energy source for autochthonous soil microorganisms and as a source of new metabolically active organisms, contributing to the increase of biodegradation rates. The results of the present work indicate that the addition of compost is effective in the remediation of petroleum hydrocarbons contamination, promoting the improvement of the soil physical, chemical and biological conditions and being a sustainable technique with positive impacts from the environmental, social and economic points of view.
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Estudo da resposta IP de solos argilosos contaminados por hidrocarbonetos e chorume / A study on the IP response from clayey soils contaminated by hydrocarbons and inorganic co mpounds.Andréa Teixeira Ustra 28 June 2013 (has links)
A tese de doutoramento apresenta uma pesquisa que teve como objetivo principal estudar a resposta IP gerada pela contaminação de solos argilosos por compostos orgânicos e inorgânicos. Ensaios de campo e laboratório foram realizados para investigar a sensibilidade do método IP à mudanças na propriedades petrofísicas provocadas pela contaminação. Um experimento controlado investigou o efeito IP gerado em amostras coletadas em torno de um aterro de resíduos urbanos, saturadas por diferentes concentrações de chorume, coletado no próprio local. Os resultados mostram um aumento do efeito IP em amostras ricas em CaCO3, observado mesmo para altas concentrações de chorume. Um segundo experimento controlado investigou o efeito do teor e tipo de argila e da salinidade na resposta IP. Misturas de esferas de vidro e diferentes teores de caulinita e montmorilonita foram saturadas por soluções de diferentes concentrações de NaCl. Os resultados obtidos mostram que o efeito da concentração de sais na resposta IP depende do teor de tipo de argila, sendo esse último dominante em relação ao efeito da salinidade. A concentração de sais e o teor de argila atuam de forma acoplada, intensificando o efeito IP. Em um terceiro experimento, a sensibilidade da resposta IP a presença de tolueno foi investigada. Misturas de areia e montmorilonita foram artificialmente contaminadas por diferentes concentrações de tolueno. Os resultados desse experimento mostram que o efeito desse contaminante na resposta IP é pequeno. Ainda assim, foi possível observar uma dependência da resposta IP com a concentração de tolueno que muda com o tempo, provavelmente devido a mudanças interfaciais químicas após a adição de tolueno. Com o objetivo de estudar o efeito da biodegradação do tolueno em solos argilosos na resposta IP gerada, duas colunas compostas de uma mistura de areia e caulinita, artificialmente contaminadas por tolueno, foram preparadas. Um fluxo de água subterrânea coletada em uma área contaminada foi estabelecido em uma das colunas (ativa), enquanto que uma solução de água deoneizada e NaCl foi estabelecido na outra (controle). A resposta IP das duas colunas foi monitorada por um período de quatro meses e nenhuma mudança na resposta elétrica das colunas que indicasse a ocorrência de biodegradação do tolueno foi observada. Os dados geoquímicos comprovam que não houve mudanças significativas durante o período do monitoramento, mesmo embora a presença de bactérias anaeróbicas vivas tenha sido verificada tanto na solução de entrada como na solução de saída da coluna ativa. Uma possível explicação para o tolueno não ter sido biodegradado de forma eficiente é a sua alta concentração na colunas. O último estudo realizado consiste na utilização do método IP para a investigação de uma área contaminada por BTEX (benzeno, tolueno, etil-benzeno e xileno). A contaminação ocorreu devido a derrames acidentais de quantidade não estimada de solventes no solo não impermeabilizado. O ensaio de campo revela uma zona de anomalia, caracterizada por baixas resistividade e cargabilidade e aumento da cargabilidade normalizada. Amostras de solo foram coletadas na área e tiveram suas propriedades elétricas medidas em laboratório. O contraste elétrico observado em campo não foi observado em laboratório, sugerindo que variações do teor de umidade podem estar contribuindo para a anomalia geofísica observada em campo. O teor de argila, bactérias totais e propriedades magnéticas foram medidas em diversas amostras coletadas na área. Os resultados dessas análises mostram que a distribuição do teor de argila não explica a anomalia observada. Entretanto, a população microbiana encontrada foi cinco ordens de magnitude maior na zona de anomalia. As propriedades magnéticas mostram que as amostras coletadas na zona da anomalia são mais ricas em magnetita. Os estudos realizados nessa pesquisa mostram que a resposta IP observada em estudos ambientais é afetada por propriedades petrofísicas como o teor de argila, teor de umidade, mineralogia e propriedades químicas do fluido dos poros. Entretanto a variação natural dessas propriedades também é esperada em ambientes dinâmicos. Consequentemente, isolar a contribuição de mudanças dessas propriedades devido a contaminação é uma tarefa complexa. / This PhD Thesis presents a research that aimed to study the IP response from soils contaminated by organic and inorganic compounds. Field surveys and laboratory experiments were conducted to investigate the sensibility of the IP method to changes in petrophysical properties due to contamination. A controlled experiment investigated the IP effect generated in soil samples collected around an urban waste disposal site, saturated by the leacheate generated at the site. The results show an IP effect increase on samples rich in CaCO3, observed even for high contaminant concentrations in the saturation solution. A second experiment investigated the effect of clay type and content and salinity on the IP response. Glass beads with varying concentration of kaolin and bentonite mixtures were synthesized and saturated by solutions with varying salt concentration. The results of this experiment show that the effect of salinity on the IP response depends upon clay type and content, being the clay effect dominant over the salinity effect. The effects of ionic concentration and clay content on the IP effect are coupled, enhancing the IP response. In a third experiment, the IP sensibility to toluene contamination is investigated. Sand and montmorillonite mixtures were artificially contaminated with varying toluene concentrations. The results show that the toluene effect on the IP response is small. Even though, there is an IP response dependency on toluene concentration that changes with time, probably due to interfacial chemical properties changes after the addition of toluene. With the purpose of studying the effect of toluene biodegradation on the IP response, two columns were packed with a sand and kaolinite mixture, artificially contaminated with toluene. A contaminated groundwater solution flux was established in one column (active), and a NaCl and deoneized water solution flux was established on the other column (control). The IP response from both columns was monitored for a period of four months. No significant changes in the electrical properties of these columns that could indicate toluene biodegradation was observed. Geochemical data confirmed that no significant changes occurred during the monitoring period, even though live anaerobic microorganisms were verified in the active column inflow and outflow. One possible explanation for the inefficiency in degrading toluene is its high concentration in the columns. The last study presented is a BTEX (benzene, toluene, ethyl benzene and xylene) contaminated area investigated with the IP method. The contamination events took place due to accidental spills directly into the soil, where the exact amount of contaminant disposed is unknown. The geophysical survey revealed an IP response anomaly, characterized by low resistivities and chargeabilities and normalized chargeability enhancement. Soil samples were collected at the site and its electrical properties were measured in the laboratory. The electrical contrast observed in the field was not observed in the laboratory, suggesting that moisture content could be contributing to the geophysical anomaly observed at the field. Clay content, total bacteria and magnetic properties were measured for some of the collected samples. The results show that the clay content distribution in the area does not explain the geophysical response observed. However, the microbial population was found to be over five orders of magnitude higher in the anomaly zone. Magnetic properties of the samples show that the anomaly zone is richer in magnetite. These studies show that the IP response observed in environmental studies is affected by petrophysical properties such as clay content, moisture content, mineralogy and pore fluid chemical properties. However, natural changes of these properties are also expected in dynamic environments. The isolation of the contribution of soil contamination to changes of these properties is a complex task.
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AVALIAÇÃO DOS INDICADORES DE SUSTENTABILIDADE PARA OS RESÍDUOS SÓLIDOS DE BURITI ALEGRE/ GO: SUBSÍDIO AO DESENVOLVIMENTO SUSTENTÁVELRodrigues, Grazzielle Coelho 07 February 2013 (has links)
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Previous issue date: 2013-02-07 / The city of Buriti Alegre - Goiás is one of the municipalities that do not contain adequate
infrastructure at the disposal of waste in the city, 14 km to the dump houses municipal
waste, construction and electronics, among electronic mestais stand the heavy elements
that can contaminate soil and local hydrology, losses of contamination of municipal
waste cause problems in the health, economic and social / environmental sustainability
ruling in favor of the welfare of the population. The objective of this study is to assess
the Municipal Solid Waste (MSW) from the city of Goiás-Buriti Alegre, as improvement in
the urban environment and highlight the damage that the city may face a policy
sustainable without, from that offer subsidies for training a plan for solid waste
management for the city. For the study of MSW, we used the methodology proposed by
Milanez, specific for RS 2002. The 12 indicators were worked as an interview with public
officials and opinion leaders as teachers and traders of the city. They analyzed the
indicators and from this it was possible to evaluate the indicators such as favorable,
unfavorable and very unfavorable, as the application of sustainability indicators in Buriti
Alegre-Goiás, seven (70%) tended very unfavorable, three (30%) and two negative
(20%) in favor, which explains the lack of assessment and the lack of an MSW landfill.
To implement the results identified himself as the relationship gets lost in the fauna and
flora of a certain place with the incidence of a dump, we assessed the level of soil
contamination by heavy metals by analyzing physical chemistry at the dump, the goal of
analysis identified the level of contamination of heavy metals such as lead, manganese,
cadmium, mercury and tin in and out of the landfill and the interference of these
chemicals in the ecosystem. / A cidade de Buriti Alegre Goiás constitui um dos municípios brasileiros que não
contém infraestrutura adequada na disposição dos resíduos da cidade, o lixão a 14 km
aloja resíduos urbanos, de construção civil e eletrônicos, dentre os eletrônicos se
destacam os mestais pesados, elementos que podem trazer desvantagens ao
ambiente, os prejuízos da contaminação de resíduos urbanos provocam problemas no
âmbito da saúde, econômico e ambiental descartando a sustentabilidade em prol do
bem estar da população. O objetivo deste trabalho consiste em avaliar os Resíduos
Sólidos Urbanos (RSU) da cidade de Buriti Alegre - Goiás, como melhoria no ambiente
urbano e destacar os prejuízos que a cidade possa enfrentar sem uma política
sustentável, a partir disso oferecer subsídios para formação de um plano de gestão de
resíduos sólidos urbanos para a cidade. Para o estudo dos RSU, utilizou-se a
metodologia proposta por Milanez, (2002) específica para RS. Os 12 indicadores foram
trabalhados em forma de entrevista com gestores públicos, comerciantes e professores
da cidade. Os mesmos analisaram os indicadores e a partir disso foi possível avaliar os
indicadores como favoráveis, muito desfavoráveis e desfavoráveis, quanto à aplicação
dos indicadores de sustentabilidade para os gestores de Buriti Alegre- Goiás, (70 %)
apresentou tendência muito desfavorável, (30%) desfavorável e (20 %) favorável, o que
explica a falta de avaliação de RSU e a ausência do aterro sanitário. Para implementar
os resultados identificou-se o quanto se perde em relação a fauna e flora de
determinado local com a incidência de um lixão, avaliou-se o nível de contaminação do
solo para metais pesados através da análise físico química no lixão, o objetivo da
análise permitiu identificar o nível de contaminação de metais pesados de dentro e fora
do lixão e a interferências desses elementos químicos no ecossistema.
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BIODEGRADAÇÃO DE NAFTALENO EM SOLOS CONTAMINADOS POR DERIVADOS DE PETRÓLEO EM CARATINGA MG / Biodegradation of naphthalene in contamined soil by diesel hydrocarbons in Caratinga city, Minas Gerais state.Bruno Marques Gonçalves Alves 17 August 2007 (has links)
lt;p align="justify"gt; Na cidade de Caratinga existem postos de abastecimento de
combustíveis cuja vida útil dos tanques de armazenamento de combustíveis é
estimada em aproximadamente 25 anos. Ao longo do tempo os tanques,
podem apresentar desgastes, podendo ocorrer vazamentos e possíveis
contaminações do ambiente. Os maiores problemas da contaminação do solo e
das águas subterrâneas por combustível são atribuídos aos hidrocarbonetos
aromáticos, estes são os constituintes mais solúveis e móveis da fração do
diesel, tais como Benzeno, Tolueno, Naftaleno (HPAs). Estes compostos
podem atingir as águas subterrâneas e contaminá-las. Os compostos HPAs
são muito tóxicos ao sistema nervoso central do homem, apresentando
toxicidade crônica, mesmo em pequenas concentrações. O objetivo desta
pesquisa foi determinar a existência de microrganismos no solo de um Terminal
de Combustíveis em Caratinga e avaliar a capacidade dos microrganismos em
biodegradar o diesel. Foi aplicada uma metodologia para a identificação da
biodegradação do naftaleno. Os ensaios foram realizados em bancada, utilizando-se microrganismos típicos do local e exógenos para comparação. Os
resultados obtidos mostraram que ocorreu maior redução da quantidade do
naftaleno adicionado, quando foram utilizados microrganismos nativos.lt;/pgt; / lt;p align="justify"gt; In the Caratinga city many fuel supplying facilities exist and the estimated
lifetime of the fuel storage tanks are of approximately 25 years. In the long run,
these fuel tanks show signs of wearing leading to leaks and possible
environmental contaminations. The greatest problem of soil and groundwater
contamination by fuel is due to the aromatic hydrocarbons, which are the most
soluble and mobile compound of the diesel, such as Benzene, Toluene,
Naphthalene (PAHs). These compounds can reach the groundwater, and
contaminate them. The compounds of PAHs are very toxic to the central
nervous system of the human body, showing signs of chronic toxicity, even in
small concentrations. The purpose of this research was to determine the
existence of microorganisms in the soil of the Fuel Terminals in Caratinga city
and to evaluate the capacity of the micro-organisms in biodegrade diesel. A
methodology was applied study of the biodegradation of the naphthalene in
contaminated soils. Using a known mass of soil collected in the area of study,
and adding the typical microorganisms of the area as well as exogens,
previously selected and enriched. The obtained results showed greater degradation of naphthalene by typical microorganisms isolated from local
contaminated soils.lt;/pgt;
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