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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Determining suitable locations for landfill development

Chan, Zenith., 陳仕廉. January 1997 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
42

Die strafrechtlichen Bezüge des Bundes-Bodenschutzgesetzes /

Laski, Markus. January 2003 (has links) (PDF)
Univ., Diss.-2003--Göttingen, 2002.
43

Aluminum chemistry and its implications on pretreatment and disposition of Hanford waste sludge

Ruff, Timothy Joe, January 2007 (has links)
Thesis (M.S.)--Mississippi State University. Dave C. Swalm School of Chemical Engineering. / Title from title screen. Includes bibliographical references.
44

An analysis of hazardous waste across different land use zones in Musina Local Municipality, Limpopo Province, South Africa

Nematshavhawe, Happy Andani January 2021 (has links)
Thesis (M.Sc. (Geography)) -- University of Limpopo, 2021 / Hazardous wastes (HW) refer to wastes that may or tend to cause adverse health effects on the ecosystem and human beings. These wastes pose present or potential risks to human health or living organisms, due to the fact that they are: (i) non-degradable or persistent in nature, (ii) can be biologically magnified, (iii) are highly toxic and even lethal at very low concentrations. Various types of production activities in South Africa generate many by-products, which are usually discarded but often turn out to be sources of acute environmental hazards. If not contained and handled appropriately, waste, including HW can cause significant problems. Unattended HW lying around leads to unhygienic conditions resulting in health problems. Increasing population growth, accompanied by rapid urbanization and industrialization, increases the volume of HW generated in the country. Improper waste management is aesthetically unattractive and impacts negatively on tourism by creating blight on South Africa’s beautiful landscape. The aim of the study is to assess how HW is discarded across different land use zones in the Musina Local Municipality in order to reduce and manage the negative impacts that they exert to the environment and human health. The objective was to: (i) analyse the state and management of hazardous waste discarded by beauty salons of the central business district of Musina; (ii) Elucidate the state and management of hazardous waste discarded by households located in the suburbs of Musina; (iii) Document the state and management of hazardous waste discarded by automotive workshop located in the Industrial zone of Musina and (iv) Develop tailor-made recommendations for the safe management of hazardous waste in the town of Musina, Limpopo Province, South Africa The study was conducted in Musina Local Municipality in Limpopo province, South Africa. Musina is the northern town in the Limpopo Province of South Africa. The study sites were divided into three land use zones; central business district (CBD), suburban area, and industrial zone. In terms of methodology observations, a datasheet and a semi-structured questionnaire were used to collect data on HW management across three different land use zones. A total of 73 semi-structured questionnaires (55 in suburban area and 10 in industrial zone and 8 in the Central Business District) were employed to document quantitative and qualitative data. Observations were used to identify the types and document quantity of HW discarded by all participants. The researcher opened the weekly municipal refuse bags that stored discarded products to list and count HW products. The information was captured on a datasheet, which recorded data on type, quantity and separation of hazardous waste from general waste. Data was analysed via descriptive statistics. Results from Central Business District (Salons) shows that nail varnish bottles were the most discarded HW product with 250 discarded per week by all eight salons. Other HW products discarded include artificial nails, hair dye containers, plastic combs, vinyl gloves and disinfectant containers. All salons practice the same disposal method; making use of municipal refuse bags for temporary storage, which is then transported to the municipal landfill site for final disposal. None of the participants separate waste; reasons being lack of awareness of separation management. Shop owners and employees’ attitude towards HW management was neutral while their level of knowledge on the environmental and human health impact was rated low. Seventy-five percent of the respondents were not aware that the products they discard are hazardous. Results from Suburban area (household hazardous waste) shows that home cleaning products were the most discarded Household Hazardous Waste (HHW) product with 237 discarded per week by all 55 sampled households. Other HHW products discarded include personal cleaning products, miscellaneous items, automotive maintenance and gardening products. The 50 households practice the same disposal method; making use of house bin (usually pedal bins). Once the bin is full, they dispose it to the outdoors wheelie bins. The remaining five household dispose of their waste directly to the outdoor bin. None of the participants separated waste; main reasons being lack of awareness of separation management. Participants’ attitude towards HW management was neutral while their level of knowledge on the environmental and human health impact was rated medium. Seventy-three percent of the respondents were aware that the products they discard are hazardous. Results from Industrial Zone (hazardous waste) shows that plastic components were the most discarded hazardous waste (HW) product with 31 discarded per week by all 10 sampled automotive workshops. Other HW products discarded include lead-acid batteries, automotive used oil and paint containers. Automotive workshops practice different storage and disposal method; making use of drums, large containers and old scrap car as a temporary storage place. Once the temporary storage is full, 50% opted for recycling while 30% dispose of their waste to the landfill site; the remaining 20% burn their waste in their premises. A large majority (80%) did not separate their waste; main reasons being a lack of awareness of separation management. Participants’ attitude towards HW management was positive while their level of knowledge on the environmental and human health impact was rated low. Half of the respondents were aware that the products they discard are hazardous. Many studies have looked at the comparison between wastes discarded in the rural versus urban area with little attention on specific enterprises. It is more realistic to consider other enterprises because different activities generated different waste. This study was able to assess how waste is discarded in different enterprises such as salons and automotive workshop with an addition of residential waste. To the best of our knowledge this is the first study of this kind. Future research can look at other enterprises such as HW from restaurant or as far as HW discarded by mining sector. The study recommends that the salon enterprise obtains a HW certificate prior to operating a salon, this will increase awareness and make employees more knowledgeable on issues relating to the management of HW. Most of the wastes discarded by sub-urban area were recyclable materials. The municipality can look into collecting recyclable materials separately and taking it to the recycling facilities. It was shocking to find out that there are automotive industries that burn their waste (without even separating). This poses a serious danger in terms of air pollution and the possibilities of containers exploding; therefore, there is an urgent need to educate people in the automotive industry. Keywords: Hazardous waste, Household Hazardous Waste, Musina, Central Business District
45

Community-based environmentalism in transitional South Africa: social movements and the development of local democracy

Buchler, Michelle 30 January 2017 (has links)
A dissertation submitted to the Faculty of Arts at the University of the Witwatersrand, Johannesburg, in partial fulfilment for the degree of Master of Arts. Johannesburg 1995. / This report explores co llect+ve ect+on around opposition to a propo..;ed hazardous waste 1andf t 11. Of concern ;s the role that social movement organisations and social movement activists, organising around environmental issues, can play in entrenching a participatory, non-racial democracy in South Africa's present transitional political phase. The analysis makes use of theories of social movements which argue that collective action is rooted in previous cycles of mobilisation, and that the role of social movement entreprenbJrS or activists is crucial in coll,ctive action mob'l Hsat ton. Data was collected through the use of participant observation and semi-structured interviews, Various documentary sources were also used. This report argues that mobilisation around environmental issues can best be understood by locating such mobilisation in the heritage of previous cycles of mobilisation, most notably in the period of the 19805. Furthermore, this report highlights the fact that the structure and form of ~he transitional state at national, regional and local levels presents certain constraints with regard to the extension and entrenchment of participatory democracy, Finally, it will be argued that while the Chloorkop Coalition demonstrates the pctent ial that environmental issues have for uniting communities across traditional racial and ideological barriers, it ;s not clear whether a lasting cross~racial cooperation can be achieved. / MT2017
46

Hazardous Waste Site Proximity and Type 2 Diabetes: From Youths to Adults

Johnson, Theresa Ann 01 January 2019 (has links)
Type 2 diabetes has reached epidemic proportions in adults and youths. Persistent organic pollutants and endocrine-disrupting chemicals (EDCs), such as pesticides, dioxins, and organochlorines, are omnipresent and persist in the environment with potential for human exposure via contaminated air, waterways, soil, and human food supply. EDCs have been correlated with diabetes incidence and risks. Residential proximity to hazardous waste sites (HWS) has been correlated with increased hospital admission rates for diabetes. The study used a sample population (N = 1,724), ages ≥ 12 years from the 2005-2012 Continuous NHANES and HWS data from the National Priorities List of Superfund Sites. The ecosocial theory of disease distribution, and geocoordinates provided theoretical support. Mann-Whitney U test and binary logistic regression analysis were used to investigate the relationship between residence ≤ 1 mile compared with residence >1 mile from a HWS in NHANES surveyed counties of NJ, PA, NY, and CA on the outcome abnormal A1c ≥ 5.7% while controlling the effect of the moderators: abnormal body mass index (BMI), age, sex, and race/ethnicity on the relationship. Participants with a BMI ≥ 28.95 kg/m2 were 1.8 times and persons ≥ 58 years of age were 2.1 times more likely to have an A1c ≥ 5.7%. Also, non-Hispanic Whites residing >1 mile of a HWS had 82.1 % reduced risk of abnormal A1c compared with the same group residing ≤ 1 mile of a HWS. The results forge opportunities for future studies to consider border distance between residence and HWS. In addition, the results may promote positive social change through diabetes risks education, environmental health education, and practices and raise dialogue about social justice and the geographic distribution of hazardous waste sites.
47

Surfactant-Assisted Zerovalent Iron Dechlorination Of Polychlorinated Biphenyl In Contaminated Sediment / Remédiation de sédiment contaminé par des polychlorobiphényls par déchloration réductive au fer zérovalent assistée par tensioactif

Wu, Yingxin 24 May 2016 (has links)
La contamination des sols et sédiments par les polychlorobiphényls (PCB) pose un problème sanitaire et environnemental à l’échelle mondiale, en raison de la récalcitrance et de la toxicité de ces composés. L’objectif de cette thèse est de chercher un procédé de remédiation de sédiments contaminés aux PCB en utilisant le fer zérovalent (Fe0). D’abord, une campagne de prélèvement a été menée sur des sites contaminés par le recyclage des déchets électroniques en Chine du sud. La contamination en PCB n’était pas aussi forte que prévue, mais la présence de métaux lourds accentue la difficulté de la remédiation. Ensuite, a été étudiée la déchloration des PCB par le Fe0 en solution aqueuse, en présence de métaux et surfactants. Les résultats ont montré la déchloration progressive des PCB et révélé l’itinéraire réactionnel avec la spécificité des congénères et la régio-spécificité. L’importance relative des facteurs qui influent se classe selon : tensioactif > acide humique > pH > Ni2. La décontamination du sédiment a été étudiée par 1) lavage avec une solution aqueuse de tensioactif suivie de la déchloration des PCB en solution et 2) mélange direct avec le Fe0 et les tensioactifs. La seconde approche s’est avérée prometteuse pour la remédiation / Soil and sediment contamination by polychlorinated biphenyls (PCBs) is a global health and environmental concern, since PCBs are toxic and recalcitrant. The aim of this thesis is to find a remediation process to PCBs contaminated sediments by using zerovalent iron (ZVI). To begin the studies on remediation, a survey was conducted on sites contaminated by e-waste recycling activities in south China. PCBs contamination was not as severe as previously, whereas the co-existence of PCBs and heavy metals increases the difficulty of remediation. Afterwards, the feasibility PCBs degradation by ZVI in aqueous solutions was investigated. Results confirmed the stepwise dechlorination of PCBs by ZVI and the major pathway with congener specifity and regiospecifity. The relative importance of the influential factors to ZVI degradation of PCBs was in the order of surfactants > humic acid > pH > Ni2+. Sediment decontamination was studied by 1) washing with an aqueous solution of surfactant followed by ZVI dechlorination of PCBs and 2) direct mixing with ZVI and surfactant solution. The second approach gave promising results for remediation
48

Assessing Environmental Inequality in Portland, Oregon: An Exploration of Local Environmental Justice Struggles

Folks, Jordan Douglas 01 January 2012 (has links)
This thesis explores patterns of environmental inequality in Portland, Oregon; both the existence of spatial environmental inequalities and the structural and local forces which contribute to them. Research on environmental inequality, or inequitable exposure to toxins, has shown that minority and low-income populations experience the bulk of the exposure to environmental hazards. Although Portland is often cited as the archetype of a sustainable city, environmental inequality is a pervasive issue. This thesis examines the health inequalities that characterize underserved communities in Portland. Utilizing a mixed methods approach, the researcher uses 1) logistic regression to statistically assess the relationship between race, poverty, and Superfund site locations, and 2) in-depth interviews with members of Oregon's environmental justice movement to help understand the historical, social, political, and economic conditions of Portland and their subsequent influence on environmental inequalities. Quantitative data is pooled from 2000 census and 2011 Environmental Protection Agency (EPA) sources. The quantitative findings demonstrate that environmental inequality is present in Portland, with African Americans being particularly overrepresented in tracts with Superfund sites. The quantitative analyses ultimately suggest that minimally populated, highly impoverished tracts with approximately 11% African American residents are most likely to house a Superfund site. The qualitative findings show that a variety of structural and local forces play prominent roles in the formation of Portland's environmental inequalities. The qualitative analyses reveal this to be a multifaceted and complex process that is indicative of Portland's history of racial inequality, contemporary free market and business forces, and governmental interests which culminate in trends of inequitable development.
49

Fighting the growth machine : can minorities be saved from its harmful effects?

Reale, Nicole 01 July 2003 (has links)
No description available.
50

Characterization And Lime Stabilization Studies On Artificially Lead Contaminated Soils

Gaurave, Kumar 07 1900 (has links) (PDF)
Hazardous waste substances are solid, semi-solid or non-aqueous liquids that exhibit characteristics of corrosivity, reactivity, ignitability, toxicity and infectious property. Major available options for management of hazardous waste include direct disposal into landfill or chemical treatment/stabilization of wastes prior to landfill disposal. Hazardous wastes are accepted for direct disposal in engineered landfills if they conform to the chemical concentration limit criterion (determined by water leach test followed by estimation of the concentration of the contaminant) and compressive strength (the material should have compressive strength > 50 kPa) criterion. Lead is classified as extremely toxic metal. Elevated levels of lead in water (surface and ground water) primarily arise from industrial discharges, and aerial deposition. During its residence in surface water bodies, the lead may interact detrimentally with aquatic life or be abstracted into public water supplies. According to National drinking water standards, the permissible limit of lead in drinking water is 0.05 mg/l. Deposition of air-borne lead, disposal of sewage sludge on land and disposal of industrial effluents on lands are major sources of lead contamination of soils. When incorporated in soil, lead is of very low mobility. Lead retained in soils can be slowly leached to the groundwater thereby impacting human health if consumed for potable needs. Alternatively lead deposited in soils can be absorbed by vegetation (crops/trees) and can impact human health on their consumption. Given the negative impacts of lead contamination on human health, the strong affinity of soils to retain deposited lead and the possible release for human consumption, this thesis focuses on characterization and chemical stabilization of artificially lead contaminated soils in the context of their disposal in hazardous waste landfills. The main objectives of the thesis are: characterize artificially lead contaminated soils for water leachability of lead and undrained strength characteristics as per CPCB (Central Pollution Control Board) guidelines in the context of disposal criteria in hazardous waste landfills. Artificially lead contaminated soils in compacted and slurry states are used in the thesis. Red soil (from Bangalore District, Karnataka) and river sand are used in the preparation of compacted and slurry specimens. The red soil and red soil-sand specimens are artificially contaminated in the laboratory by employing aqueous lead salt solutions as remolding fluids. Lead concentrations of 160 to 10000 mg/l are used in this study. The results of characterization studies with artificially lead contaminated soils help identify contaminated soil materials that require chemical stabilization prior to disposal into engineered landfills. Based on the results of characterization studies with artificially lead contaminated soils, lime stabilization coupled with steam curing technique is resorted to immobilize lead in the red soil-sand slurry specimens and mobilize adequate undrained strength to meet the criteria for disposal of lead contaminated soils in hazardous landfills. After this first introductory chapter, a detailed review of literature is performed towards highlighting the need to undertake chemical stabilization of artificially lead contaminated soils in Chapter 2. Chapter 3 presents a detailed experimental program of the study. Chapter 4 presents the physico-chemical and mechanical characterization of the artificially lead contaminated soils. The ability of artificially contaminated soils to release (artificially added) lead during water leaching is explained using lead speciation results performed using the Visual MINTEQ program. Experimental results illustrated that contamination of compacted red soil and red soil + sand specimens with significant lead concentrations (21 to 1300 mg/kg) resulted in major fractions of the added lead being retained in the precipitated state. Results of water leach tests revealed that lead concentrations released in the water leachates are far less than (0.0011 to 0.48 mg/l) limits prescribed by CPCB (2 mg/l) for direct disposal of lead contaminated materials into hazardous waste landfills. Unconfined compressive strengths developed by the lead contaminated red soil and red soil-sand specimens were significantly higher (100-2700 kPa) than the strength requirement (> 50 kPa) for direct disposal of hazardous wastes in engineered landfills. Lead contamination did not affect the unconfined compression strengths of the specimens as matric suction prevalent in the unsaturated compacted soils had an overriding influence on the cementation bond strength created by the lead precipitates. Visual Minteq tool was helpful in predicting the amount of added lead that was converted to insoluble precipitate form. However the amounts of water leachable lead determined experimentally and predicted by Visual Minteq were very different-Visual Minteq predicted much higher amounts of water leachable lead than experimentally determined. Experimental results revealed that the levels of lead released by the red soil-sand slurries in water leach tests were in excess (13 to 36 mg/l) of the permissible lead concentration (2 mg/l) for direct disposal of hazardous waste in landfills. Owing to water contents generally being in excess of their liquid limit water contents (w/wL ratio > 1) the slurry specimens exhibited undrained strengths below 1 kPa. Lime stabilization and steam curing of the contaminated slurry specimens was therefore resorted to control the leachibility of lead and increase undrained strengths to acceptable limits. Chapter 5 deals with lime stabilization of artificially contaminated slurries that do not meet the leachate quality (lead concentration in water < 2 mg/l) or compressive strength (> 50 kPa). Procedures are evolved for lime stabilization of such artificially contaminated soils to meet both the water leachate quality and compressive strength criteria. Lime stabilization together with steam curing of the lead contaminated slurry specimens effectively immobilized the added lead (2500 mg/kg) and imparted adequate compressive strengths to the contaminated red soil-sand slurry specimens. The lime stabilized contaminated specimens released marginal lead concentrations (0.03 to 0.45 mg/l) in the water leach; these values are much lower than permissible limit (2 mg/l) for disposal in hazardous landfills or values exhibited by the unstabilized specimens (13 to 38 mg/l). Lime addition rendered the contaminated specimens strongly alkaline (pH values ranged between 10.68 and 11.66). Combination of the experimental and Visual Minteq results suggested that precipitation of lead as hydrocerrusite in the alkaline environments (pH 10.68 to 11.95) is not the sole factor for marginal release of lead in water leach tests of the 4, 7 and 10 % lime stabilized contaminated specimens. It is possible that fraction of lead ions are entrapped within the cemented soil matrix. Water leach tests performed at range of pH values (pH 2.5 to 9.6) with 7 % lime stabilized specimens suggested that immobilization of lead as hydrocerrusite or as entrapment in the cemented soil mass in the lime stabilized specimens is practically irreversible even on exposure to extreme pH conditions. The lime stabilized contaminated specimens developed unconfined compressive strengths ranging from 100 kPa (4 % lime stabilized 40 % red soil-60 % sand specimen) to 1000 kPa (10 % lime stabilized 100 % red soil specimen). The significant growth of compressive strength upon lime stabilization is attributed to growth of inter-particle cementation bonds by the CAH (calcium aluminate hydrate) and CSH (calcium silicate hydrate) compounds formed by lime-clay reactions, slight reduction in void ratios and growth of strong inter-particle cementation bonds the during steam curing at 800C. The results of this thesis bring out a procedure to immobilize high concentrations of lead and develop adequate compressive strength of lead contaminated slurry specimens by lime stabilization + steam curing technique. The red soil acted as pozzolana in reactions with lime, while, steam curing accelerated the lime-soil reactions. The procedure can be extended to non-organic slurry wastes that are devoid of pozzolanic material (example, lead contaminated smelting sands). In slurry wastes devoid of pozzolana, materials such as fly ash can be added and the reactions between lime and fly ash would immobilize lead + develop adequate compressive strength. Also, similar to the methodology being adaptable for any non-organic slurries, it can also be extended to other toxic metal bearing wastes, example, zinc, cadmium and nickel.

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