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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

Uranium mining, primitive accumulation and resistance in Baker Lake, Nunavut: recent changes in community perspectives

Bernauer, Warren 17 March 2011 (has links)
Historically, the Inuit of Qamani’tuaq (Baker Lake) have expressed strong opposition to uranium mining in their territory, in part due to concerns that it would be detrimental to their harvesting practices. During these struggles, the Inuit of Qamani’tuaq had the support of various Inuit Organizations. The first decade of the 2000s saw the relevant Inuit Organizations change their policies from ones which opposed uranium mining to ones which support it. This thesis is an attempt to understand if Inuit at the community level have changed their opinions about uranium mining and, if so, why. During my time in Qamani’tuaq, it became apparent that the shift in policy has been followed by a gradual change in perspective among some members of the community. While opposition to uranium mining is by no means dead, the seemingly united stance the community previously held has become fragmented. This change is due to a number of factors, including an increased astuteness on the part of the mining industry, certain aspects of the Nunavut Land Claims Agreement and ongoing economic dependency upon the market economy.
2

Uranium mining, primitive accumulation and resistance in Baker Lake, Nunavut: recent changes in community perspectives

Bernauer, Warren 17 March 2011 (has links)
Historically, the Inuit of Qamani’tuaq (Baker Lake) have expressed strong opposition to uranium mining in their territory, in part due to concerns that it would be detrimental to their harvesting practices. During these struggles, the Inuit of Qamani’tuaq had the support of various Inuit Organizations. The first decade of the 2000s saw the relevant Inuit Organizations change their policies from ones which opposed uranium mining to ones which support it. This thesis is an attempt to understand if Inuit at the community level have changed their opinions about uranium mining and, if so, why. During my time in Qamani’tuaq, it became apparent that the shift in policy has been followed by a gradual change in perspective among some members of the community. While opposition to uranium mining is by no means dead, the seemingly united stance the community previously held has become fragmented. This change is due to a number of factors, including an increased astuteness on the part of the mining industry, certain aspects of the Nunavut Land Claims Agreement and ongoing economic dependency upon the market economy.
3

Respiratory health status in relation to occupational exposure in uranium mining and recovery

Swiegers, Wotan Reynier Siegfried 20 September 2010 (has links)
Objective The objective of this study is to examine the exposure- response relationship between prolonged exposure to low levels of silica, uranium, radon progeny and criteria pollutants and the respiratory health of uranium workers. Method Initially two pilot studies were done on selected groups of high-risk workers to determine the prevalence of alpha-1-antitrypsin deficiency and the retained burden of uranium in the lungs of exposed workers. The value of sputum cytology was also evaluated. A cross-sectional study was conducted in 1984 to determine the prevalence of spirometric abnormalities among uranium miners. The data from non-smokers without symptoms was used to develop lung function reference values relevant for the present population. Follow up analytical cross-sectional and case control studies were done in 1996 and 1999 to determine the mean independent effect of uranium on the respiratory health of miners and to detect abnormalities in both smokers and non¬smokers. Data was collected on employment history, smoking habits, pulmonary function and chest radiographs. To determine the independent mean effect of uranium mining on the respiratory health of workers, only data of non-smokers in exposed cohorts were compared with unexposed control cohorts. Results The prevalence of alpha-1-antitrypsin appeared to be high in workers with abnormal spirometric indices. The lung burden of retained uranium in workers in the final product recovery area was within normal limits. The sputum cytology was abandoned because it was found worldwide that cytological screening had no impact on population survival rates. Lung function prediction equations derived from multiple linear regressions were calculated for the study population which differed from Schoenberg et al prediction equations. The data from the analytical cross-sectional study in1996 suggests that the level of exposure in this study group (without the confounding effect of cigarette smoking) is not associated with statistically significant impairment of lung function, increased prevalence of silicosis, tuberculosis and respiratory cancer. Only the FEF75 was found to be an indicator of early lung abnormality. Data from the 1999 study supports the hypothesis that there is a small but significant exposure-response relationship between prolonged exposure to low levels of silica dust, and lung function abnormalities (in the absence of radiologically diagnosed silicosis). The prevalence of chronic obstructive pulmonary disease (COPD) and small airways disease (SAD) was small but significantly higher in exposed workers. The risk of developing COPD was 2.7 times higher for exposed workers. The risk for non-smokers was small but significant. The incidence of tuberculosis and lung cancer was not higher than expected (probably because ex-employees were not fully investigated). Conclusion Calculation of location specific prediction equations, for different ethnic groups is advocated to enable the earliest detection of lung function abnormalities. FEF75 could be used as an early indicator of lung function impairment (provided strict quality control is maintained). Exposure to a combination of silica dust, radon progeny and smoking was associated with an increased risk of lung function abnormalities, but not with tuberculosis, silicosis and lung cancer. Conclusive assessment must await sufficient latency, and ex-employees must be investigated to establish the true magnitude and distribution of the effects of siliceous and uranium dust on the health of workers (which may continue after exposure cease). / Thesis (PhD)--University of Pretoria, 2010. / School of Health Systems and Public Health (SHSPH) / Unrestricted
4

Investigating the cause(s) of benthic macroinvertebrate community impairment downstream of two Saskatchewan uranium operations

Robertson, Erin Lee 29 December 2006
Past monitoring has noted benthic macroinvertebrate community impairment downstream of both the Key Lake and Rabbit Lake uranium operations in northern Saskatchewan, Canada. The objective of this research was to try to identify the cause(s) of these impacts using a weight-of-evidence approach. Given that sediments generally accumulate contaminants that are related to metal mining activities (such as metals and radionuclides), the initial hypothesis for this research was that contaminated sediments were the primary cause of benthic community impairment at both operations.<p>In 2003 and 2004 a Sediment Quality Triad (SQT) approach confirmed the presence of an effect on benthic community structure, in addition to significant differences in surface-water, pore-water and whole-sediment chemistry at the immediate down-stream exposure sites at both uranium operations. However, no significant adverse effects were noted in 10-d whole-sediment bioassays with <i>Hyalella azteca</i>, although this lack of response could be partially due to sediment pore-water dilution resulting from the automated clean overlying water renewal process employed. Potential causes of benthic community impairment identified through the 2003 and 2004 SQTs for Key Lake include physical sediment composition, surface water pH and total ammonia, in addition to pore-water total ammonia and arsenic. Potential stressors identified at Rabbit Lake included high surface water manganese and uranium concentrations, and increases in pore-water total ammonia, manganese, iron, arsenic, and uranium levels.<p>In the summer of 2004, 4-d in-situ bioassays using <i>H. azteca</i> were conducted along with the SQTs to investigate the role both contaminated surface water and sediment played in benthic community impairment in-situ. Results from the Key Lake in-situ bioassay demonstrated that surface-water was the primary cause of acute toxicity to <i>H. azteca</i>. Results from the Rabbit Lake in-situ study also demonstrated that surface water as the primary cause of acute toxicity to <i>H. azteca</i>, although the relationship was not as strong. The cause of in-situ toxicity at Key Lake could not be correlated with any of the variables measured within the in-situ study, including trace metals, total ammonia, and pH. Of the measured constituents at Rabbit Lake, only concentrations of uranium in both surface water and pore-water were suspected of causing the observed in-situ mortality. Two data sets from two methods of surface water and pore-water collection supported these conclusions.<p>Due to time constraints and stronger cause-effect relationships, efforts were focused on the in-situ toxicity observed at Key Lake. Surface water collected in 2004 at the time of the related in-situ study was also found to be acutely toxic to <i>H. azteca</i> in separate laboratory surface water bioassays, thus verifying that contaminated surface water, not sediment, was the primary cause of the observed in-situ <i>H. azteca</i> mortality. Further information revealed that organic mill-process chemicals, which have been previously linked with sporadic effluent toxicity, were released at the Key Lake operation during the time of the in-situ experiment and associated surface water collection. Additional surface water samples collected in June and August, 2005, were not acutely toxic to <i>H. azteca</i>. Furthermore, a second bioassay with archived surface waters from the initial 2004 collection demonstrated that the water was no longer acutely toxic (i.e., acute toxicity disappeared after one-year storage). Chemistry comparisons of the toxic and non-toxic surface water samples, verified that trace metals, ammonia, pH, and major ions, including sulphate, were not the cause of toxicity, leaving only organic mill-process chemicals as a possible cause. Subsequent 4-d laboratory toxicity tests demonstrated that these process chemicals (kerosene, amine, and isodecanol) are toxic to H. azteca at the levels released in 2004, and are therefore believed to be the cause of the <i>H. azteca</i> mortality seen in the earlier in-situ experiment.<p>In short, this weight-of-evidence research provided new information on the possible causes of benthic macroinvertebrate community impairment downstream of both the Key Lake and Rabbit Lake uranium operations.
5

Mining and Sustainability? Systems and Stakeholder Analyses of Uranium Mining in Namibia

Pietrzela, Mateusz January 2013 (has links)
Roughly 10% of the Namibian GDP and over 40% of total exports are dependent on themining sector. Namibia is one of the five leading uranium producing countries worldwide withperspectives to triple the production in the following years. This study aims to identify the implicationsto sustainable development of the country carried by such a strategy to stimulate the economic growth.The complexity of the issue is addressed by an interdisciplinary set of methods leading to a betterunderstanding of processes linking uranium mining in Namibia with the environment, society and theglobal economy. Regulatory, trade and production systems are outlined and assessed, after which astakeholder analysis is conducted in order to determine who are the most influential actors as well asparties affected by the uranium production in Namibia. The results reveal a great dependence of the Namibian uranium mining sector on external factors, with the government perceived as the most affected stakeholder.
6

Investigating the cause(s) of benthic macroinvertebrate community impairment downstream of two Saskatchewan uranium operations

Robertson, Erin Lee 29 December 2006 (has links)
Past monitoring has noted benthic macroinvertebrate community impairment downstream of both the Key Lake and Rabbit Lake uranium operations in northern Saskatchewan, Canada. The objective of this research was to try to identify the cause(s) of these impacts using a weight-of-evidence approach. Given that sediments generally accumulate contaminants that are related to metal mining activities (such as metals and radionuclides), the initial hypothesis for this research was that contaminated sediments were the primary cause of benthic community impairment at both operations.<p>In 2003 and 2004 a Sediment Quality Triad (SQT) approach confirmed the presence of an effect on benthic community structure, in addition to significant differences in surface-water, pore-water and whole-sediment chemistry at the immediate down-stream exposure sites at both uranium operations. However, no significant adverse effects were noted in 10-d whole-sediment bioassays with <i>Hyalella azteca</i>, although this lack of response could be partially due to sediment pore-water dilution resulting from the automated clean overlying water renewal process employed. Potential causes of benthic community impairment identified through the 2003 and 2004 SQTs for Key Lake include physical sediment composition, surface water pH and total ammonia, in addition to pore-water total ammonia and arsenic. Potential stressors identified at Rabbit Lake included high surface water manganese and uranium concentrations, and increases in pore-water total ammonia, manganese, iron, arsenic, and uranium levels.<p>In the summer of 2004, 4-d in-situ bioassays using <i>H. azteca</i> were conducted along with the SQTs to investigate the role both contaminated surface water and sediment played in benthic community impairment in-situ. Results from the Key Lake in-situ bioassay demonstrated that surface-water was the primary cause of acute toxicity to <i>H. azteca</i>. Results from the Rabbit Lake in-situ study also demonstrated that surface water as the primary cause of acute toxicity to <i>H. azteca</i>, although the relationship was not as strong. The cause of in-situ toxicity at Key Lake could not be correlated with any of the variables measured within the in-situ study, including trace metals, total ammonia, and pH. Of the measured constituents at Rabbit Lake, only concentrations of uranium in both surface water and pore-water were suspected of causing the observed in-situ mortality. Two data sets from two methods of surface water and pore-water collection supported these conclusions.<p>Due to time constraints and stronger cause-effect relationships, efforts were focused on the in-situ toxicity observed at Key Lake. Surface water collected in 2004 at the time of the related in-situ study was also found to be acutely toxic to <i>H. azteca</i> in separate laboratory surface water bioassays, thus verifying that contaminated surface water, not sediment, was the primary cause of the observed in-situ <i>H. azteca</i> mortality. Further information revealed that organic mill-process chemicals, which have been previously linked with sporadic effluent toxicity, were released at the Key Lake operation during the time of the in-situ experiment and associated surface water collection. Additional surface water samples collected in June and August, 2005, were not acutely toxic to <i>H. azteca</i>. Furthermore, a second bioassay with archived surface waters from the initial 2004 collection demonstrated that the water was no longer acutely toxic (i.e., acute toxicity disappeared after one-year storage). Chemistry comparisons of the toxic and non-toxic surface water samples, verified that trace metals, ammonia, pH, and major ions, including sulphate, were not the cause of toxicity, leaving only organic mill-process chemicals as a possible cause. Subsequent 4-d laboratory toxicity tests demonstrated that these process chemicals (kerosene, amine, and isodecanol) are toxic to H. azteca at the levels released in 2004, and are therefore believed to be the cause of the <i>H. azteca</i> mortality seen in the earlier in-situ experiment.<p>In short, this weight-of-evidence research provided new information on the possible causes of benthic macroinvertebrate community impairment downstream of both the Key Lake and Rabbit Lake uranium operations.
7

Long term heavy metal contamination from leakage water sediments

Brodd, Patrick January 2004 (has links)
No description available.
8

Long term heavy metal contamination from leakage water sediments

Brodd, Patrick January 2004 (has links)
No description available.
9

Relationships between water quality, species composition, biodiversity and ecosystem function in lakes and flooded pits exposed to uranium mining activities in Northern Saskatechewan

Helps, Devin Murray 25 May 2009
Uranium mining activities have the potential to impact aquatic systems through mine drainage (runoff) and the release of treated effluent into nearby watersheds. Such anthropogenic exposure can lead to elevated concentrations of metals and major ions, which may impact aquatic biota. Previous studies have looked at the effects of water quality on aquatic biota within flooded pit lakes and natural lakes that have been exposed to various mechanisms of mining exposure. However, the literature often only examines the effects of a limited number of contaminants on a limited number of species. Researchers have rarely looked at the effects of multiple contaminants on species composition, biodiversity and ecosystem function in aquatic systems. This study uses a multivariate approach to look for relationships between water quality (24 variables), plankton species composition and abundance, biodiversity (richness and evenness) and ecosystem function among lakes exposed to mining activities (n = 18) and non-exposed reference lakes (n = 8). Lake water quality data was used to cluster lakes into groups. Lake groups were then overlain onto multivariate ordinations derived from species composition-abundance data to determine if species composition was related to water quality. Ecosystem function variables included planktonic phosphorus cycling and planktonic respiration. The classified lake groups clustered well on ordinations derived from species composition-abundance data suggesting that relationships exist between water quality and plankton species composition. However, ecosystem function was similar among the majority of lakes and flooded pits despite differences in species richness, species composition and species abundance. Only a small number of aquatic systems had ecosystem function properties that were different from the majority of lakes and pits. These systems had the greatest concentrations of contaminants and had very low biodiversity (richness and evenness) compared to the other systems. Despite having differences in plankton species composition and species richness, all lake groups were functionally similar. This suggests that functional redundancy in species composition may be present in the majority of lakes and pits in such a way that ecosystem function is maintained.
10

The relationship between environmental agreements and environmental impact assessment follow-up in Saskatchewan's uranium industry

Birk, Jasmine Angie 27 May 2009
Environmental Impact Assessment (EIA) is a planning process used to predict, assess, mitigate, and monitor the potential environmental and social impacts that may be associated with a proposed development project. Essential to the efficacy of EIA is follow-up - a post-decision process that attempts to understand EIA outcomes and provides feedback on project development and learning processes to improve environmental management practices. While considerable literature on follow-up related themes exists, the actual implementation and engagement of all stakeholders involved with follow-up in post-consent decision stages lacks or is not done well. That being said, in northern Canada, and in the mining sector in general, much of this post-decision activity is occurring under a new institutional arrangement: privatized community-industry Environmental Agreements and associated community-based monitoring programs. Based on a case study of follow-up in northern Saskatchewans uranium mining industry, this thesis examines both the institutional development of EIA follow-up and the role and contribution of community-based Environmental Agreements to EIA follow-up and impact management practices. This thesis adopted a manuscript-style format; both utilized a combined methodology of document review and semi-structured interviews. The first manuscript focuses on the institutional development of follow-up in the northern Saskatchewan uranium mining industry, giving context to the current situation. Results demonstrate that follow-up in Saskatchewans uranium industry has transformed and is characterized by four themes ranging from little or no follow-up to a new system that now includes a participatory yet privatized process based on privatized agreements. Results suggest that follow-up has evolved to a current emphasis on environmental management incorporating a community-centric approach, recognition of socioeconomic issues in monitoring programs, and an increased community and industry presence in follow-up and monitoring activities. The second manuscript examines the nature and scope of the northern Saskatchewan uranium industrys Environmental Agreement and its potential role in EIA follow-up. Results indicate that although privatized Environmental Agreements and community-led monitoring programs complement and supplement formal EIA follow-up processes and contribute to environmental management practices, they do not have the capacity to replace EIA follow-up. Results from this thesis advance current knowledge and understanding of the evolution of EIA follow-up and the current role and contribution of privatized agreements to post-decision follow-up and impact management practices.

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