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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.
1

An analysis of public participation in the Alcan aluminum smelter review process

Hendrickson, Lorna Y.R. January 1984 (has links)
This report discusses public participation in a Megaproject Environmental Assessment and Review Process, specifically, the Alcan aluminum smelter review process. Two methods are employed to assess the Alcan process - the first, a review of related literature on public participation and environmental assessment processes. Secondly, a survey of public attitudes and concerns towards the megaproject assessment and review process. A set of ideal guidelines for government, industry or proponent, and the public to follow in an environmental assessment and review process is developed. These guidelines are discussed in chapter seven of the report, along with a critique of the events that occurred in the Alcan review process. A modified megaproject environmental assessment and review process is developed, based on the results of the review of related literature; attitude survey; and an examination of the Manitoba Environmental Assessment and Review Process and the review process formulated to review the Alacan proposal. This modified Megaproject Environmental Assessment and Review Process is presented and discussed in chapter seven. Four recommendations are advanced in chapter eight specific to the Alcan process. These recommendations apply more generally to the Manitoba Environmental Assessment and Review Process. In summary, I recommend: 1) A legislative basis to the Manitoba Environmental Assessment and Review Process; 2) An expanded definition of environment to include the socio-economic environment; 3) Financing of legitimate interest groups; and 4) A clear definition of the Environmental Assessment and Review Process. This should outline all opportunities for public involvement; information for the public on the review process; opportunity for the public to participate in the development and review of the EIA guidelines and completed environmental impact statement; and requiring both government and industry to involve the public in the review process.
2

Rationality and politics in bureaucratic decision-making: a study of thesecond aluminium decision to establish a smelter in New Zealand

Miller, Anthony John January 1982 (has links)
In July 1980 the National Government selected a proposal by the Fletcher-Alusuisse-Gove consortium for the establishment of an aluminium smelter which would take up the last and greatest part of a 5000 Gigawatt-hour electricity concession. This decison provides a convenient end-point for a long and complicated period of energy planning where a major concern has been the utilisation of surplus energy resources. The history of this decision will be traced in this study beginning with the discovery of the surplus energy resources in 1978. A considerable part of this decision-making has been conducted inside the government bureaucrary and in secret. This study focuses exclusively on this bureaucratic decisionmaking providing a detailed discussion of the energy planning issues and also endeavouring to treat the decision as the outcome of organisational processes. It is an important theoretical concern that only through an understanding of behavioural processes can the importance of managing the decision process be fully appreciated. Some of the circumstances in which this study was undertaken must be mentioned in order to explain the approach that has been adopted. The structure of this study has been largely determined by the requirements of a second report which is a detailed chronology of events commissioned by the Treasury. It has been through producing this Treasury report that access has been permitted to departmental files providing by far the greatest amount of research material. Access to government officials has also been assisted. However, because of the requirements of the Treasury report and the sensitivity of the issues covered, it has not been possible to interview key participants in the decision outside the government bureaucracy. It should also be noted that the controversy which has marked the public debate on the aluminium smelter and associated issues has also been evident in the bureaucratic decisionmaking where sharp interdepartmental differences appeared. This context has meant that when the interviewing was carried out in late 1980 and early 1981, many officials still felt unable to give a completely frank and detailed account of events. Despite these circumstances, many officials have been of considerable assistance to me and have been very generous with their valuable time. In particular I wish to acknowledge the assistance given to me by Mr Rob Laking and Mr Howard Fancy. I am also grateful for the kind and patient supervision offered to me by Professor Keith Jackson and for the generous services of Mr Richard Kennaway and Dr. Keith Ovenden.
3

The use of soil amendments in the revegetation of smelter-impacted soils near Flin Flon, MB/Creighton, SK

2014 June 1900 (has links)
Some areas near Flin Flon, MB and Creighton, SK are devoid of vegetation due to a variety of mining, smelting, forestry activities and forest fires that have occurred since the 1930’s. This study investigated the use of soil amendments to enhance revegetation in these areas. The study was comprised of two main components, an in situ study and a growth chamber trial. The in situ component was conducted to determine the efficacy of soil amendments that could be utilized in a revegetation program. The growth chamber trial examined if the amount of moisture present in the soil would have an influence on the success of vegetation survival and growth. The in situ study was conducted near Flin Flon, MB and Creighton, SK over two growing seasons and consisted of replicated treatments imposed at 12 sites. Tree seedlings [trembling aspen (Populus tremuloides Michx.) and jack pine (Pinus banksiana Lamb.)] and understory species [tufted hairgrass (Deschampsia cespitosa L.) and American vetch (Vicia americana Muhl.)] were planted at each site. Each site also received soil amendments; bone meal and meat biochar (BMB), compost, commercial mycorrhizal inoculant (EMF) and, willow biochar (WB) in combination with dolomitic limestone and fertilizer. Each site also had a control that received an application of only dolomitic limestone and fertilizer. The growth chamber trial utilized the same plant species and soil amendments as the field trial with the exclusion of willow biochar. In general, soil amendments did not influence the survival or growth of the tree seedlings in situ or in the growth chamber trial. However, the compost amendment increased survival and growth of the tufted hairgrass significantly in the growth chamber trial and to a lesser extent in the field trial. Compost also positively influenced the pH and base saturation of the soil compared to the other amendments. The mycorrhizal inoculant increased the rate of mortality of tree species in the growth chamber trial. Moisture did not influence the survival and growth of the seedlings or understory species or the efficacy of the amendment treatments in this study.
4

Sulphur Isotope Fractionation in Smelter Emission Streams and Precipitation Sudbury, Ontario

Snyder, Warren 04 1900 (has links)
<p> International Nickel Company's 1250 ft. stack located in Sudbury, Ontario emits an estimated 3,000 tons of sulphur oxide daily. The purpose of this study is to investigate the use of stable sulphur isotopes as a means of tracing the movement of these sulphur oxide emissions. Sulphur isotope analysis were done for lakewater, rainwater and sediment samples taken from the Sudbury-Timagami district and also for particulate and gas samples taken from the 600 ft. level of the International Nickel Company's 1250 ft. stack. </p> <p> The s s^34 values of lake surface samples showed a decrease related directly to the increase of the logarithm of the distance from Sudbury. The maximum s s^34 value for the lakewater samples was + 8.49 p.p.t. at a distance of 7 miles from Sudbury. The minimum s s^34 value for lakewater samples was+2.97 p.p.t. at a distance of 55 miles from Sudbury. </p> <p> The rainwater s s^34 values vary from + 4.85 p.p.t. recorded for a station 5 miles north of Sudbury to + 2.07 p.p.t. for a station 60 miles east north east of Sudbury. </p> <p> The increase in s s^34 values in the lakewater relative to rainwater strongly suggest that the oxidation of so2(g) to s4^2- is occurring in the lakes in the Sudbury-Timagami district. </p> / Thesis / Bachelor of Arts (BA)
5

Development of an air quality model for BCL Limited

Tshukudu, Tiroyaone 04 May 2005 (has links)
In order to understand the impact from a point source of pollution a comprehensive air quality monitoring programme must be in place. Measurement stations are at fixed locations and can only measure the relevant concentration if the wind is blowing in a particular direction. With changing wind direction, a measurement station needs to be coupled with a dispersion model to predict the impact from a point source, such as the BCL Limited smelter. The smelter produces 55 500 tonnes per annum of nickel/copper granules; in the process emitting waste gases to the atmosphere through a 153 m stack. The EEGAIR-BCL1. dispersion model was developed for BCL Limited to complement the air quality monitoring programme in the Selebi-Phikwe area. The model was developed for the smelter specifically, using local meteorological data at Selebi-Phikwe and smelter specific emission data. Results from the model were tested against data obtained from existing measurements stations at Selebi-Phikwe for May 2002, using statistical analyses. The average index of agreement indicates that the model predictions were more accurate for Kopano (0,44) and SPSS (0,25) stations than for WUC (0,08) station. Yearly averaged emission data was used for model input and better correlation can be expected when using actual hourly and/or monthly emission data. Based on the EEGAIR-BCl1 dispersion model results, it was found that the highest impact from the smelter stack was at a distance of 4 km to 7 km west from the stack. The model results indicate that, on average, the impact from the smelter stack in residential areas of Selebi-Phikwe was between 0 and 50 µ/m3 for May 2002. / Dissertation (MEng(Environmental Engineering))--University of Pretoria, 2006. / Chemical Engineering / unrestricted
6

Base metal losses to furnace slag during processing of platinum-bearing concentrates

Andrews, Lesley 22 January 2009 (has links)
The base metal distribution in, and losses to, Anglo Platinum six-in-line and slag cleaning furnace slags were characterised to coincide with various process changes at Waterval Smelter from 1999 to 2009. The base metals are presumed to be reliable indicators of PGE losses and are easier to detect and measure than these elements are. In addition, base metal and sulphur levels are used to monitor and control many smelter processes, including slag cleaning and converting. Some losses to slag are recoverable but others are not – these have been quantified during this study. Slag composition and smelting temperatures have varied substantially, and optimisation of the slag cleaning furnace – a first for the South African platinum industry – has produced a wide variation in oxidation conditions. Most of the base metal losses in the slag cleaning furnace are mechanically entrained matte particles, the largest of which should be recovered. These have been examined to establish any relationship between composition, size, and depth within the furnace so that recommendations can be made to limit these types of losses. In the six-in-line furnaces, over half of base metal losses to slag are as dissolved phases, which are not recoverable. Levels of dissolved metals have been measured and related to furnace operating conditions and slag composition. The prediction of such base metal losses is not easy, because the slag compositions are so complex. One aspect of the project has been to compare the measured distribution of the base metals with those calculated using the FactSage equilibrium model, to identify problem areas, and to recommend actions which could improve the predictions of this and similar modelling programs for base metal dissolution in slag. New electron microbeam techniques have been developed to quantify base metal distribution in slag, and novel combinations of these techniques with analytical chemistry and Mössbauer Spectroscopy have been pioneered. / Dissertation (MSc)--University of Pretoria, 2009. / Materials Science and Metallurgical Engineering / unrestricted
7

Evaluation of thermal desorption as an alternative technique for the measurement of coal tar pitch volatiles / Cornelius Johannes van der Merwe

Van der Merwe, Cornelius Johannes January 2011 (has links)
Motivation: The accurate and reliable measurement of the concentration of coal tar pitch volatiles (CTPVs) in ambient air has proved to be a challenge for occupational hygienists. The challenge must however be confronted due to, amongst others, the carcinogenic properties of some poly–aromatic hydrocarbons (PAHs) contained in CTPVs. Aim: To determine the feasibility of a thermal desorption (TD) technique based method as an alternative method to be used for the measurement of the concentration of CTPVs in ambient air by assessing it along criteria such as ease of use, cost, accuracy and precision by comparing it to NIOSH’s Method 5515 and OSHA’s Method 58 and to determine the level of exposure to CTPVs on the anode paste floor of an electric furnace, used for the smelting of platinum group metals (PGMs) concentrate. Methodology: To satisfy the research objective, two accepted methods the National Institute of Occupational Safety and Health’s (NIOSH) method 5515 and the Occupational Safety and Health Administration’s (OSHA) method 58 were used for the measurement of the concentration of CTPVs with a TD technique based method used as a third, alternative method. All three methods were used concurrently to measure the concentration of CTPVs in ambient air, at the anode paste floor of a platinum group metals (PGMs) concentrate smelter. Results and conclusions: The NIOSH method proved to be the most precise method while the TD technique based method proved to be the most accurate. The TD technique based method proved to measure the widest range of individual CTPVs and were able to measure the highest concentration of Benzo(a)pyrene, an individual CTPV that is classified as a Group 1 (carcinogenic to humans) chemical substance by the International Agency for Research on Cancer (IARC). The OSHA method measured on average almost four times less total CTPVs than either the NIOSH or the TD technique based method and failed to readily measure individual CTPVs with a molecular weight lower than that of Phenanthrene. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2012.
8

Evaluation of thermal desorption as an alternative technique for the measurement of coal tar pitch volatiles / Cornelius Johannes van der Merwe

Van der Merwe, Cornelius Johannes January 2011 (has links)
Motivation: The accurate and reliable measurement of the concentration of coal tar pitch volatiles (CTPVs) in ambient air has proved to be a challenge for occupational hygienists. The challenge must however be confronted due to, amongst others, the carcinogenic properties of some poly–aromatic hydrocarbons (PAHs) contained in CTPVs. Aim: To determine the feasibility of a thermal desorption (TD) technique based method as an alternative method to be used for the measurement of the concentration of CTPVs in ambient air by assessing it along criteria such as ease of use, cost, accuracy and precision by comparing it to NIOSH’s Method 5515 and OSHA’s Method 58 and to determine the level of exposure to CTPVs on the anode paste floor of an electric furnace, used for the smelting of platinum group metals (PGMs) concentrate. Methodology: To satisfy the research objective, two accepted methods the National Institute of Occupational Safety and Health’s (NIOSH) method 5515 and the Occupational Safety and Health Administration’s (OSHA) method 58 were used for the measurement of the concentration of CTPVs with a TD technique based method used as a third, alternative method. All three methods were used concurrently to measure the concentration of CTPVs in ambient air, at the anode paste floor of a platinum group metals (PGMs) concentrate smelter. Results and conclusions: The NIOSH method proved to be the most precise method while the TD technique based method proved to be the most accurate. The TD technique based method proved to measure the widest range of individual CTPVs and were able to measure the highest concentration of Benzo(a)pyrene, an individual CTPV that is classified as a Group 1 (carcinogenic to humans) chemical substance by the International Agency for Research on Cancer (IARC). The OSHA method measured on average almost four times less total CTPVs than either the NIOSH or the TD technique based method and failed to readily measure individual CTPVs with a molecular weight lower than that of Phenanthrene. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2012.
9

Aerosol Physicochemical Properties in Relation to Meteorology: Case Studies in Urban, Marine and Arid Settings

Wonaschuetz, Anna January 2012 (has links)
Atmospheric aerosols are a highly relevant component of the climate system affecting atmospheric radiative transfer and the hydrological cycle. As opposed to other key atmospheric constituents with climatic relevance, atmospheric aerosol particles are highly heterogeneous in time and space with respect to their size, concentration, chemical composition and physical properties. Many aspects of their life cycle are not understood, making them difficult to represent in climate models and hard to control as a pollutant. Aerosol-cloud interactions in particular are infamous as a major source of uncertainty in future climate predictions. Field measurements are an important source of information for the modeling community and can lead to a better understanding of chemical and microphysical processes. In this study, field data from urban, marine, and arid settings are analyzed and the impact of meteorological conditions on the evolution of aerosol particles while in the atmosphere is investigated. Particular attention is given to organic aerosols, which are a poorly understood component of atmospheric aerosols. Local wind characteristics, solar radiation, relative humidity and the presence or absence of clouds and fog are found to be crucial factors in the transport and chemical evolution of aerosol particles. Organic aerosols in particular are found to be heavily impacted by processes in the liquid phase (cloud droplets and aerosol water). The reported measurements serve to improve the process-level understanding of aerosol evolution in different environments and to inform the modeling community by providing realistic values for input parameters and validation of model calculations.
10

Mortality and morbidity in lead smelter workers with concomitant exposure to arsenic

Lundström, Nils-Göran January 2007 (has links)
Arsenic is a well-known lung carcinogen in humans. In 2006, IARC upgraded inorganic lead as a possible human carcinogen (2A). The aim of this thesis has been to evaluate the lung cancer mortality and incidence in long-term exposed primary lead smelter workers and also to estimate present exposures to arsenic and lead in relation to those occurring in the past. The basic cohort (N=3832 workers; hired before 1967 and followed up from 1950-1981; SMR comparisons with general and local reference populations) showed an excess of deaths for total mortality, malignant neoplasms (e.g. lung and stomach cancer), ischaemic heart diseases, and cerebrovascular diseases compared to the general population. In a subcohort of lead workers (N=437; regular blood lead sampling since 1950) only the raised SMR for lung cancer (162) was sustained. In a follow-up study of the basic cohort (N=3979), a subcohort of lead exposed workers (N=1992) was formed. The expected mortality in 1955-1987 and cancer incidence in 1958-1987 were calculated relative to county rates. A cumulative blood lead index (CBLI) was used for dose-response analyses. The lung cancer incidence was raised in the total cohort (SIR 2.8; 95 % CI 2.1 3.8). A higher lung cancer risk was observed in workers hired before 1950 (SIR 3.6; 95 % CI 2.6-5.0). The increased lung cancer risks were further elevated in the subcohort of lead exposed workers, especially in the highest exposed subgroup (SIR 5.1; 95 % 2.0-10.5; latency period of 15 y). No excesses of other malignancies were observed. The increased relative risks for lung cancer may have been caused by interactions between inorganic lead and other substances at the smelter, e.g. arsenic. To further analyze the effects from inorganic lead, two subcohorts of workers at the lead departments were formed from the original cohort (N=3979), one of 710 workers and the other of 383 workers. The lung cancer incidence was raised in both subcohorts (Lead subcohort 1; SIR 2.4; 95 % CI 1.2-4.5; Lead subcohort 2; SIR 3.6; 95 % CI 1.2-8.3). Among the 10 workers that had developed lung cancer in lead subcohort 1 all but one had a considerable exposure also to arsenic. Thus, a possible interaction effect between lead and arsenic may explain the increased lung cancer risks. To further elucidate the impact from lead and arsenic a case control study was undertaken. In the basic cohort (N=3979), 46 male workers had contracted respiratory malignancies. They were compared with 141 agematched male referents from the primary smelter by conditional logistic regression analysis using smoking habits, cumulative blood lead and air arsenic exposure as predictor variables. The lung cancer cases showed a significantly higher smoking rate than referents (Odds ratio, OR = 4.0; 95 % CI 1.6-10.1; p=0.003). When restricted to smokers, the cumulative arsenic air exposure index, but not the lead exposure indices, were significantly higher among the cases (OR=1.07; 95 % CI 1.02-1.11; p = 0.005). Accordingly, cumulative arsenic exposure and smoking were identified as significant risk factors for the development of lung cancer in the final analyses, while lead exposure was not a significant risk factor. However, inorganic lead still may play a minor role in the multifactorial genesis of lung cancer. These studies describe risks from exposures occurring from time periods before 1950 up to 1981. Because of the long latency period for lung cancer, exposures after 1970 probably have had limited impact on the reported results. Compared to the levels in the early 1970´s present exposures to arsenic are lower by a factor of ten or more and risks probably correspondingly lower.

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