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Nitrogen and phosphorus modification within a petroleum contaminated biopile at the Oneida County Sanitary Landfill /Nieuwenhuis, Jenifer M. January 2004 (has links) (PDF)
Thesis--University of Wisconsin--Stevens Point, 2004. / Includes bibliographical references (leaves 108-110).
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Influences of particulate-associated petroleum conversion products on the interactions of trace metals with Kuwait marine sedimentsAl-Ya'koob, Sami Ne'mah Mohammad. January 1990 (has links)
Thesis (DR. P.H.)--University of Michigan.
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Bioremediation of petroleum hydrocarbon contaminated soil /Vogdt, Joachim, January 1992 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 108-111). Also available via the Internet.
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Atmospheric fluxes and the geochemistry of n-alkanes in Crystal Lake (Vilas County), WisconsinDoskey, Paul Vincent. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 142-153).
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Using algae as environmental impact indicators in urban freshwater pondsJohnstone, Claire January 2003 (has links)
Urban freshwater ponds are bodies of water that sustain a diversity of higher plants, vertebrates, invertebrates, amphibians and algae. The importance of ponds in the enhancement of diversity in urban habitats is little understood due to a lack of available knowledge of the processes and interactions that operate within the biotic components of these small aquatic ecosystems. The objectives of this study were to explore the use of algae as indicators of the biotic and abiotic challenges that occur in Sustainable Urban Drainage Systems (SUDS) and to investigate the relationships between algal population dynamics, and stress physiology and water chemistry and quality. An output of this study is the recommendation of management strategies which support the sustainable enrichment of diversity in SUDS. A longer-term consideration is to explore the potential for developing algae as potential phytoremediators in SUDS ponds. Three ponds were studied in Duloch Park, Dunfermline, Fife. Water quality and algal distribution studies indicated that excessive nutrient loads from surface water runoff, caused the ponds to become eutrophic during most of the course of the study. The ponds were particularly impacted by periodic inputs of suspended solids, road salts, and runoff from construction sites and soil erosion incidents. <i>Cladophora glomerata</i> (filamentous blanket weed) was the major algal species present in the ponds and was thus selected as the key indicator organism throughout the study. Due to the short pond retention times, planktonic microalgal populations were extremely low despite adequate nutrient supplies being available. Chlorophyll <i>a/b</i> ratios for <i>C. glomerata</i> fell below the normal chlorophyll ratio of 2.6:1 indicating excessive exposure to high irradiance. A relationship may also exist between the decline in <i>C. glomerata</i> abundance and heavy metal accumulation in the sediments, competition effects due to excessive plant growth of <i>Phragmites australis</i> and duckweed and pond turbidity. At the biochemical level the investigation of a total antioxidant assay (based on the chemical reagent ABTS) was developed for <i>C. glomerata</i> to assess sub-cellular stress responses as markers of environmental change. Fluctuations in total antioxidant activity were assigned to combinations of biotic and abiotic stress, life cycle changes and turbidity impacts within the ponds. More detailed studies of individual antioxidants (superoxide dismutase, catalase, peroxidase, glutathione reductase and glutathione-stransferase) demonstrated that <i>C. glomerata</i> had increased SOD activities. Enzymes associated with the removal of toxic H<sub>2</sub>O<sub>2</sub> were detected in samples from specific locations and time frames. Depletion in protective non-protein and protein bound SH groups in certain pond samples indicated a significant level of oxidative stress possibly caused by xenobiotics. High levels of glutathione reductase activity were detected in all <i>C. glomerata</i> samples suggesting efficient enzyme recycling. It is proposed that this helps protect algal cell membranes from further oxidative damage. As sampling of algae from ponds is restricted to seasonal growth patterns and availability of algal mats an <i>in vitro</i> assay was devised to detect oxidative markers of stress ( OH) <i>in vitro</i>. This was developed using the microalga <i>Euglena gracilis</i> and comprised a non-destructive gas chromatographic technique. Experiments were constructed to simulate xenobiotic stresses <i>in vivo</i>. Cells exposed to high iron and salt concentrations at levels similar to those detected in the ponds, demonstrated high antioxidant activities, suggesting that algae and specifically <i>E. gracilis</i> may be a suitable candidate for phytoremediation programmes in SUDS. The study concludes by presenting an integrated scheme demonstrating the importance of understanding SUDS biotic components at environmental, physiological and biochemical levels. Using this scheme recommendations for improving pond management strategies are made with a view to maximising the biological potential, diversity and sustainability of SUDS ponds in the Scottish urban landscape.
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Total emission analysis of sewerage systems and wastewater treatment plantsJack, Andrew G. January 1999 (has links)
The proposed methodology to most effectively manage intermittent combined sewage discharges into urban watercourses in the UK is given in the Urban Pollution Management (UPM) manual. The method is based on the use of detailed computer models of the sewerage system, wastewater treatment plant and receiving watercourse. Solving intermittent discharge problems using UPM, often requires the installation of in-sewer storage tanks. However, recent research from Germany and elsewhere (e.g. Austria and Denmark) has shown that this type of solution may be of little benefit with respect to the total emissions discharged from the entire system, where emissions from both the Combined Sewer Overflows (CSOs) and the Wastewater Treatment Plant (WTP) are considered together. This is because, in certain situations, WTP efficiency can be compromised by the prolonged periods of dilute (low nutrients and substrate) inflows which can result from the draining down of in-sewer storage tanks. The earlier research in Germany and elsewhere has been concerned with long term total emissions (annual loads) and not the problems specific to individual sites, or the benefits and/or limitations of storage with respect to acute pollution. Thus the principal objective of the research described here has been to substantiate and quantify the total emission problem by means of detailed modelling, via an evaluation of the likely storage volumes which could give rise to total emissions problems for the Perth wastewater system. Following this, a general method has been developed to investigate and resolve total emission problems related to acute pollution effects. As WTP disruption due to flow dilution can last for a prolonged period after even a single rainfall event, computational simulation times need to be long enough to represent the delay in WTP performance returning to normal operating conditions. As long term continuous simulation is usually impractical due to protracted computational times, a method referred to as the Total Emission Analysis Period (TEAP) has been developed. This will define the minimum required computational time and rainfall inputs to be used to ensure that the effect of in-sewer storage on total emissions could be modelled. Utilising the TEAP method to analyse total emissions it has been concluded that increasing volumes of storage would not be expected to create a total emission XXVI problem with respect to the Biochemical Oxygen Demand (BOD). Consequently, it was concluded that the best storage volume with respect to BOD was the minimum volume which would allow compliance with receiving water quality standards. No direct comparison could be made with the conclusion derived from the German research due to the long term nature of their analysis, however, it would appear from an interpretation of their results, that similar findings were obtained. With respect to ammonia, it was found that increases in total emissions can occur as, ammonia concentrations, unlike BOD, do not increase at the start of a storm due to first foul flush effects. Consequently, any increased emissions from the WTP would not be offset via a reduced CSO spill load. It was also found, however, that increasing volumes of storage would not be expected to exacerbate acute pollution problems within a receiving watercourse and that both large and small storage volumes had the potential to give rise to very similar degrees of WTP disruption. This was due to the way in which different hydraulic loading conditions (caused by the different volumes of storage) affected the bacterial concentrations in the reactor. The conclusion that storage would not provide a significant benefit for ammonia total emissions was supported by the Austrian and Danish research.
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Modelling nitrification in the River Zarka of JordanAbumoghli, Iyad January 1993 (has links)
No description available.
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Development and evaluation of multistage filtration plants : an innovative, robust and efficient water treatment technologyGalvis, Gerardo January 1999 (has links)
1. This thesis addresses the major problem of providing 'safe' drinking water to small rural and urban populations, which are dependent upon polluted surface water sources. The problem is addressed in the context of the Andean highlands of Colombia and based on gravity flow systems, but the solutions proposed may be applicable in other parts of the world. 2. The central hypothesis of the thesis is that the appropriate combinations of different type of filtration stages provide a uniform quality of water of low risk to consumers. Where institutional and community development make chemical disinfection constantly reliable, the addition of low dose terminal disinfection should be enough to ensure that the drinking supply is safe. 3. The hypothesis was initially tested in the Cauca River valley at pilot scale. A range of designs of upflow, downflow and horizontal flow coarse gravel filters followed by slow sand filtration were compared in an intensive evaluation for their ability to remove key water quality parameters. A novel dynamic fine gravel filter was developed by the author and introduced in advance of the coarse gravel filters to cope with peaks of suspended solids. 4. Highly improved filtrates were achieved during the pilot scale trials and detailed comparative analyses demonstrated the strengths and weaknesses of all component stages. Bacteriological and turbidity removals were particularly impressive compared with earlier studies in Peru and elsewhere. The most efficient combinations of filtration stages consistently achieved five-log faecal coliform removal and this contributed to the full-scale application of the technology within the region. 5. Full scale systems in a range of locations in the Cauca Valley, and elsewhere in Colombia, have demonstrated convincingly that the combination of dynamic gravel filtration, single or multistage coarse gravel filtration and slow sand filtration provide a robust, reliable and efficient technology. It can be successfully operated and maintained at community level, and even without terminal disinfection, multistage filtration provides a consistently low risk drinking water. The inclusion of terminal disinfection provides a fail-safe barrier against occasional high peaks of pollution. 6. The work carried out during the course of this thesis has established multistage gravel filtration as an essential technology when dealing with polluted waters of highly variable quality, and more appropriate and economical than so-called 'conventional' water treatment for small to medium size rural and urban communities. 7. The research has introduced and established dynamic fine gravel filters as a vital and economical component in multistage filtration, which is capable of dealing with occasional high peaks of pollution within established routines of maintenance. 8. The studies on full-scale systems over the past 5 to 10 years have demonstrated that the technology is sustainable in the hands of local operators as a result of a participatory and joint- learning project approaches. 9. The limits of the technology with respect to extremes of raw water quality have been defined. A selection procedure to identify and combine filtration stages in a treatment plant is proposed. It is based on a set of treatment objectives, contamination levels in raw water sources, and removal efficiencies expected at each treatment stage.
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Long-term assessments of some vessel-source marine pollutantsDixon, Trevor January 1997 (has links)
Accidental and deliberate discharges from maritime transportation activities have been widely perceived as major sources of pollution. Preventive and control management strategies have therefore been progressively introduced internationally to reduce and eliminate these inputs to the marine environment. The long-term effectiveness of these measures, applied to vessels operating in the waters around the British Isles, is the research question that has been under investigation by the author since 1971. Following analyses of stakeholders' interests and concerns, and associated information requirements, the aims and objectives of a phased work programme were identified. These focused primarily upon three vessel-source marine pollutants; oil or oily mixtures, packaged dangerous or harmful goods and garbage. After a review of the literature, assessment strategies, designs, methodologies and analytical techniques were devised and applied over varying spatial and temporal scales. A data acquisition and management system, utilising questionnaire returns from 13 reporting organisations, was employed to support an annual survey on marine oil pollution. A similar approach, combined with published information, facilitated a characterisation of packaged chemical incidents around the coastline and changes over time. To determine different sources and other attributes of marine litter, an ocean-focused beach survey design was devised and applied on the shores of the English Channel, Irish Sea, North-East Atlantic Ocean and North Sea. A series of surface drift experiments and an open-water sighting survey provided further information on movements and densities of marine litter in the open sea. Research outputs, including the publications submitted, have been reviewed and identified as authoritative sources of information by the competent authorities and other interested parties. These include the Department of the Environment, Transport and the Regions, European Commission, International Maritime Organisation, Royal Commission on Environmental Pollution, Smithsonian Institution for Short-Lived Phenomena and the United States National Oceanic and Atmospheric Administration.
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Microcolumn field sampling and flow injection techniques for mercury speciationWei, Jian January 1993 (has links)
Mercury is one of the most toxic heavy metals, and many serious incidents have resulted from mercury poisoning. The methylation of mercury and its amplification by marine life have aggravated this pollution problem. Studies over the last three decades have shown that the toxicity of mercury is related to chemical form. A basic aim of the research has been to devise new methodology for the measurement and speciation of mercury. Key points of the investigation reported were the literature review of methodologies and techniques for mercury speciation and the development of a novel manifold which incorporates microcolumns of sulphydryl cotton which have a relatively high affinity and selectivity for inorganic and / or organomercury, and to utilise a continuous flow procedure for mercury speciation based on flow injection-atomic fluorescence spectrometry. This new and novel system has been used for the determination and speciation of mercury in a variety of water samples. The other column packing materials, eg. xanthate cotton, activated alumina and 8-hydroxy-quiniline were also investigated. A further aspect of element speciation concerns the development of a field sampling technique using sulphydryl cotton columns. Sample collection and preconcentration using microcolumns at the site of sampling was successfully performed. Preliminary experiments indicated that the field sampling technique in combination with FIA-AFS was a robust and potentially useful speciation tool. Field surveys on mercury distribution and speciation in the Manchester Ship Canal and the River Rother have been intensively carried out in collaboration with the National Rivers Authority (North West Region). The analytical data on different mercury species in waters of the Manchester Ship Canal are reported for the first time. A high correlation between organomercury and organolead in the Manchester Ship Canal is found and the related data have been assessed in order to clarify the possible origins for organomercury. Related work concerning participation in interlaboratory studies is reported in the Appendices.
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