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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.
391

Awakening the city of seven hills: a transportation hub to enhance mobility for wellness in Kampala Uganda

Namutebi, Sheila Sarah January 2019 (has links)
A research report proposal submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, in partial fulfillment of the requirements for the degree of Masters of Architecture (Professional). January, 2019 / In recent years, research studies have shown an increase in stress levels especially among people living in cities. Clear links have been established correlating wellbeing with the environment. Studies show that urban environments increase tendencies of unhappiness and stress among people. This study identifies inefficiency in systems that facilitate mobility as one of the causes of stress among city users. It recognises mobility as a core component of any system that facilitates the efficient flow of things between points. Inadequacy in systems of mobility can therefore cripple a system by preventing the free movement of things from one point to another. Like so many developing cities, the urban environment of Kampala, the capital of Uganda that is undergoing rapid urbanisation and often unchecked development faces challenges regarding mobility. In Kampala, majority of the population either walk or rely on public transportation and yet the inadequate infrastructure and systems of mobility denies them the right to freely and easily access and navigate their city. This both directly and indirectly results in physical and psychological stress in city users leading to frustrations and financial losses and consequently prevents wellbeing. The study focuses on the Old Taxi Park which is the most frequently used public transportation facility for daily short trips around the city of Kampala. Recognising that the failing state of infrastructure and inadequate systems of organising the movement of vehicles and people in and around the park render it one of the black spots that contribute to and often escalate the problems regarding mobility presents the Old Taxi Park as a suitable site for a project to address the city’s navigational challenges. This is aimed at mitigating stress among the people who engage with the city. The project thus proposes a revamp of the Old Taxi Park to facilitate efficient movement of people within Kampala. In order to further enhance wellness, the project draws on the healing and restorative power of nature. Although nature has been linked to improved well being, having been found to have numerous restorative benefits especially for people who constantly interact within densely inhabited fast paced settings, the city centre of Kampala which has the highest population density and fastest pace of life in the entire city critically lacks instances where people can interact with and so benefit from the nurture of the elements of nature. Therefore this research project takes an approach of reintroducing various elements of nature to the urban fabric through the design of the transportation hub and how it integrates with Kampala’s urban fabric. The main objectives for the project are hence to promote efficiency in the systems of mobility and to reintroduce nature within the urban sphere in order to promote wellness for the people who interact with the concrete jungle that was once the City of Seven Hills / MT 2019
392

The effects of low-level flying military aircraft on the reproductive output of osprey in Labrador and northeastern Québec /

Thomas, Peter W., 1969- January 1999 (has links)
No description available.
393

Size and shape of airborne asbestos fibres in mining and mineral processing environments

Hwang, Chung-Yung. January 1981 (has links)
No description available.
394

Educating for sustainable development : a case study of an environmental immersion school

Samuel, Hilary R. (Hilary Ruth) January 1991 (has links)
No description available.
395

Evaluation of heavy metals in soil : a case study of platinum tailing dam site

Nkobane, Molebogeng Precious 09 1900 (has links)
Mining industry has been identified as the main sustenance of the South African economy, however the negative impacts of the industry on the ecological systems cannot be over emphasized due to the released waste which is mostly heavy metals into the environment. The study evaluated six heavy metal (A1, Cu, Fe, Ni, Pb and Cr) contents in a tailings dam from a specific mine site. Two sets of samples for the investigation were measured, that is, one in year 2012 and the other in year 2013. In the year 2012, the sample set was only taken at a distance profile of 500 meters from the foot of the dam, whereas the sample set taken in the year 2013 was for the 500 and 1500 meter distance profiles from the foot of the dam. The year 2012 and 2013 sample sets for the 500m distance profile were sampled very similarly to each other. A kilogram of each sample was taken as per grid format. The samples at varied depths were taken at 0-cm depth for the top layer, 20cm depth for the second layer, and 30cm depth for the third layer. The samples for the surface varied distance were taken at 1 m, 2m, 3m, and 4m away from each 500m and 1500 sampling points. The 2012 samples were analysed using characterization methods namely ICP MS and The 2013 samples were analysed using the ICP OES. The comparison of the field results for the six heavy metals studied (A1, Fe, Pb, Cu, Ni and Cr) was performed using statistical analytical methods, namely ANOVA. The statistical analysis results for heavy metals (A1, Fe, Pb, Cu, Ni and Cr) from sample and 2013 revealed that the group means are not significantly different from each other which means that there is no significant difference in (A1, Fe, Pb, Cu, Ni and Cr) concentrations with respect to both depth and distance. The observations from both 2012 and 2013 indicate the results of the samples are in agreement. In addition, the comparative average concentrations of the three results obtained reach the same conclusion that the tailing dam probably does not introduce considerable or significant amounts of these metals (A1, Fe, Pb, Cu, Ni and Cr) into the surrounding soils. / Chemical Engineering / M. Tech. (Chemical Engineering)
396

Natural building in South Africa : assessing the niche-regime relationship through a 'latent niche' mediation

O'Rourke, Eamonn Christopher 04 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: In this thesis I examine the natural building movement in South Africa in an attempt to determine the systemic influences that appear to confine it to a small market operating at the very edge of the mainstream building sector. I make use of the conceptual framework of the multi-level perspective to explore the interrelationships between natural building as a technological niche and the mainstream building sector as the dominant regime. I extend the concept of a technological niche by appending the term 'latent' to form the term 'latent technological niche', to describe a technology with sustainability credentials that fails to break into the mainstream market, despite achieving technological maturity and constant though minimal market share. The research objectives of this thesis are to: identify pathways for the natural building niche to move beyond its latent state; to determine how the translations of natural building practices to the building sector might occur; and how this might transform the building sector regime. I explore how action research involving knowledge sharing between multi-stakeholder, niche and regime actors might stimulate debate and subsequent action to overcome entry barriers; and serve as a catalyst to advance a latent technological niche beyond its confined market. I present an action research method, a 'latent technological mediation', of facilitated 1st and 2nd order social learning. This is used as a mechanism of tapping into the immediate knowledge of actors in the socio-technical regime. The purpose being to identify the external forces and internal processes of a latent technological niche. The status of a latent technological niche is assessed by comparing these processes in the context of external forces against seven processes, presented in this thesis. These seven processes are considered crucial for a technology to break into the mainstream market and are adapted from the internal processes of success, described in the literature on strategic niche management and the characteristics of a successful 'bounded socio-technical experiment' (BSTE) described in the conceptual work on BSTE's. The potential for natural building systems to enter the mainstream building sector, particularly in South Africa, is used as a case study to apply the latent technological mediation method. The findings of this research suggest that the mainstream building sector is undergoing a transition following the path of socio-techical transformation. The uncertainty introduced by the parallel system of informal settlement, which may drive transition along the more dramatic technological substitution or de-alignment and re-alignment transition pathways is briefly explored. / AFRIKAANSE OPSOMMING: In hierdie tesis ondersoek ek die natuurlike gebou beweging in Suid-Afrika in 'n poging om die sistemiese invloede te bepaal, wat neig om dit te beperk tot 'n klein mark teen die rand van die hoofstroom gebou sektor. Ek maak gebruik van die konseptuele raamwerk van die multi-vlak perspektief om die onderlinge verband tussen natuurlike geboue, as 'n tegnologiese nis, en die hoofstroom gebou sektor, as die dominante regime, te verken. Ek brei die konsep van 'n tegnologiese nis uit, deur die aanbring van die word 'latente' om die term 'latente tegnologiese nis' te vorm. 'n Latente tegnologie nis het volhoubaarheid potensiaal maar slaag nie daarin om in die hoofstroom mark in te breek nie, ten spyte van die bereiking van tegnologiese volwassenheid en 'n konstante maar minimale mark aandeel. Die navorsing doelwitte van hierdie tesis is om: roetes te identifiseer waarlangs die natuurlike gebou nis buite sy latente toestand kan beweeg; om te bepaal hoe die 'vertalings' van natuurlike gebou praktyke aan die gebou sektor kan voorkom; en hoe dit die gebou sektor regime kan verander. Ek bestudeer hoe aksie navorsing waarby kennis tussen verskeie belanghebbendes, nis en regime betrokkenes gedeel is, kan debatteer en die daaropvolgende aksie stimuleer inskrywing hindernisse te oorkom; en dien as 'n katalisator om 'n latente tegnologiese nis te bevorder buite sy beperkte mark. Ek bied 'n aksie-navorsing metode, 'n 'latente tegnologiese bemiddeling' van gefasiliteerde 1st en 2de order sosiale leerervaring aan. Dit dien as 'n meganisme van deling in die onmiddellike kennis van die spelers in die sosio-tegniese regime. Die doel is om die eksterne kragte en interne prosesse van 'n latente tegnologiese nis te identifiseer. Die status van 'n latente tegnologiese nis is beoordeel deur hierdie prosesse te vergelyk in die konteks van eksterne kragte teen sewe prosesse, wat in hierdie tesis aangebied is. Hierdie sewe prosesse word beskou as noodsaaklik vir 'n tegnologie om in die hoofstroom mark in te breek en is aangepas uit die interne prosesse van sukses, soos beskryf in die literatuur oor strategiese nis bestuur en die eienskappe van 'n suksesvolle 'begrensde sosio-tegniese eksperiment' (BSTE) beskryf in die konseptuele literatuur oor BSTE. Die potensiaal vir natuurlike gebou stelsels om die hoofstroom gebou sektor te betree, veral in Suid-Afrika, word gebruik as 'n gevallestudie om die latente tegnologiese bemiddeling metode toe te pas. Die bevindinge van die navorsing dui daarop dat die hoofstroom gebou sektor 'n verandering ondergaan op die pad van n sosio-tegniese transformasie. Die onsekerheid veroorsaak deur die parallelle informele nedersetting, wat 'n meer dramatiese tegnologiese substitusie, of ontsporing en herbelyning kan veroorsaak, word kortliks ondersoek.
397

An empirical investigation of environmental performance and the market value of JSE listed companies

Schoeman, Pieter Stephanus Johannes Albertus 04 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: In the recent past, there has been increasing awareness of, and concern for, the impact that many companies are having on the natural and social environment. This has seen the emergence of a triple bottom line approach to business, with environmental and social metrics being used in addition to financial metrics when evaluating company performance. Despite the growing level of investment in corporate sustainability, it is not clear whether these investments are viewed positively by the market, and to what extent it creates shareholder value. To shed light on the relationship between environmental performance and financial performance, this research assignment used the event study methodology to investigate whether there is statistically significant stock market reactions to announcements relating to the environmental performance of companies listed on the Johannesburg Stock Exchange. A total of 260 news announcements related to environmental performance were collected from a variety of news sources. The 260 news announcements represented 67 different companies across 11 different industry sectors. News announcements were collected from several prominent business news sources including the Business Day, Financial Mail and the Johannesburg Stock Exchange News Service. Abnormal share returns were estimated for a three day event window around the announcement date by using the market model approach. Results were aggregated based on four different categories of environmental performance, including corporate environmental initiatives, environmental awards and certificates, negative environmental publicity and, environmental reporting, permits and licences. Consistent with related research in developed countries, this study found that the market rewards certain categories of positive environmental performance but penalises certain categories of negative environmental performance more severely. The results show that there is a significant positive market reaction to announcements of corporate environmental initiatives on the trading day following the announcement. This result indicates a positive relationship between corporate environmental initiatives and financial performance, as measured by market value. In terms of negative environmental performance, it was found that the market responds negatively to the broad category of negative environmental publicity. In particular, negative announcements from civil society and environmental groups seem to result in more significant market reactions than negative announcements from local or national government. In contrast to some studies done in developed countries, no statistically significant relationship was found between announcements of environmental awards and certificates and the market value of companies. Neither was there a statistically significant relationship between environmental reporting, permits and licences and the market value of companies. These results therefore indicate that the market is selective in its response to announcements of environmental performance.
398

Ecological relevance of suborganismal and population responses of terrestrial oligochaeta to the fungicide copper oxychloride

Maboeta, Mark Steve 12 1900 (has links)
Thesis (Ph.D)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: Copper oxychloride is a fungicide that is extensively used in vineyards in the Western Cape to treat and prevent fungal diseases. It is however not clear what the effects are on soil organisms, which play an important role in soil fertility, in South African soils. There is paucity of data linking results obtained in the laboratory to effects observed in the field, which will only become useful if a clear relation can be demonstrated. The aims of this study were to: ~ Determine the effects of copper oxychloride on field populations of earthworms and simultaneously monitor lysosomal membrane stability, measured as neutral red retention time (NRRT). ~ Validate experimental field studies by doing inventories of earthworm populations in long-term sprayed vineyards. ~ Determine the LC50 of copper oxychloride and simultaneously measuring NRRT, and linking them to the experimental field studies. ~ Conduct bioassays, burrowing activity- and soil-avoidance experiments to investigate their relations to earthworm population responses in the experimental field studies. Earthworms were sampled by hand-sorting in the field tests on treated and untreated field plots in the Western- (October 1998 - July 1999) and Northern Cape (April 1998 - October 1999). Soil samples and worms were analysed for copper contents and coelomocytes of live earthworms were used to conduct the neutral red retention assays. Acute toxicity tests were conducted over a period of 28 days during which the earthworms (Eisenia fetiday were exposed to different concentrations of copper oxychloride. Change in biomass and mortality were measured as endpoints, as well as NRRT. Bioassays, burrowing activity and soil-avoidance were conducted by exposing Aporrectodea caliginosa to grassland- and vineyard soil as well as grassland soil spiked with 60 J.1g.g-1copper in the form of copper oxychloride. Growth and mortality were recorded in the bioassays as well as copper concentrations In earthworm body tissues and substrates used over a period of28 days. Burrowing activity and soil-avoidance were determined by measuring the length of tunnels burrowed by A. caliginosa in soil profiles over a period of 4 days under different exposure regimes. Results from the field tests showed that spraying of copper oxychloride had a negative effect on earthworm populations at the prescribed application rates. NRR T in earthworms from the exposure plots was significantly (p<0.05) lower after just one spraying application. It was concluded that spraying copper oxychloride at prescribed application rates caused a decrease in field populations of earthworms and that NRRT was an early and reliable biomarker since it was indicative of later effects observed at the population level. Results obtained from the field inventory of earthworms in vineyards at Nietvoorbij, Robertson end Worcester confirmed data from the two field studies. The calculated LC50 of 882.78 I1g.g-1 for copper oxychloride and 519.40 I1g.g-1 for copper was ecologically relevant if a safety factor of 10 was applied. NRRT which manifested earlier than effects on biomass change in the acute toxicity tests, were significant when viewed against the background of responses of field populations of earthworms. From the bioassay experiments it was found that A. caliginosa exposed to copper oxychloride spiked soil had significantly (p<0.05) higher weight loss and mortality than those in grassland- and vineyard soil. This indicated that changes in biomass and mortality were indicative of population responses in the field and can be considered as ecologically relevant. Burrowing activity of A. caliginosa was significantly (p<0.05) lower in vineyard and copper oxychloride spiked soil than in grassland soil. Similarly in the soil avoidance experiments it was found that A. caliginosa avoided vineyard- and copper oxychloride contaminated soil. It is therefore concluded that burrowing activity and soil avoidance were ecologically relevant endpoints since they corresponded with population responses in the field. The study thus revealed that the long-term usage of copper oxychloride could have negative effects on earthworm populations. The spraying of copper oxychloride can have important implications on the sustainable use of agricultural soils since earthworms and other soil organisms play such an important role in soil fertility. The use of biomarkers and other ecotoxicological indicators can provide an early warning that soil organisms are under environmental stress. / AFRIKAANSE OPSOMMING: Die fungisied koperoksichloried word wyd gebruik in die Wes-Kaap om swamsiektes in wingerde te beheer en te voorkom. Dit is egter nie bekend wat die effek daarvan op Suid Afrikaanse grondbiota, wat 'n belangrike rol speel in grondvrugbaarheid, is nie. Daar is ook 'n tekort aan inligting wat die resultate van laboratoriumondersoeke in verband bring met veldstudies. Die doelstellings van die studie was om: ~ Die effek van koperoksichloried op erdwurmpopulasies in die veld te ondersoek en terselfdertyd membraanstabiliteit, as moontlike biomerker, gemeet as neutraal rooi retensietye (NRRT), te monitor. ~ Die geldigheid van eksperimentele veldstudies te toets deur ook grondanalises te doen in wingerde wat oor langtermyn met koperoksichloried bespuit is. ~ Die LC50 van koperoksichloried vir erdwurms te bepaal en terselfdertyd NRR T te meet asook om dié gegewens in verband te bring met die resultate van seisoenale veldstudies oor die uitwerking op erdwurmpopulasies. ~ Bio-evaluerings ("bioassays"), tonnelaktiwiteit- en vermydingseksperimente te onderneem en die verband tussen die toksiteitstoetse en populasieresponse, soos waargeneem in die veld, te ondersoek. Erdwurms is versamel deur handsortering tydens die veldtoetse in die Wes- (Oktober 1998 - Julie 1999) en Noord-Kaap (April 1998 - Oktober 1999) op kontrole en bespuite persele. Grondmonsters en erdwurms is spektrofotometries geanaliseer om koperinhoude te bepaal. Die selomosiete van lewende wurms is gebruik om NRR T te bepaal. Akute toksisiteitstoetse is uitgevoer oor 'n tydperk van 28 dae waartydens Eisenia fetida blootgestel is aan verskillende koperoksichloried konsentrasies. Veranderinge in biomassa en mortaliteit is bepaal asook NRRT. Bioevaluerings ("bioassays"), tonnelaktiwiteit- en vermydingseksperimente IS uitgevoer deur Aporrectodea caliginosa bloot te stel aan grasveld- en wingerdgrond asook grasveldgrond wat met koperoksichloried gekontamineer is. Groei en mortalitiet is bepaal in die "bioassays" asook koperkonsentrasies in die grond en erdwurm liggaamsweefsels oor 'n tydperk van 28 dae. Tonnelaktiwiteit en grondvermyding is bepaal deur die lengte van tonnels wat deur A. caliginosa gegrawe is te meet oor 'n tydperk van vier dae vir die verskillende blootgestelde groepe. Die resultate het aangedui dat koperoksichloriedbespuiting 'n negatiewe invloed het op erdwurmpopulasies teen die voorgeskrewe toedieningsprogram. NRRT in erdwurms van die blootstellingperseel, was beduidend (p<0.05) laer na 'n enkele bespuiting. Daar is verder bevind dat NRR T 'n betroubare en vroeë biomerker is, aangesien dit 'n aanduiding gegee het van latere effekte wat op populasievlak na vore getree het. Veldopnames in Nietvoorbij, Robertson en Worcester het die geldigheid van data verkry uit die veldstudies ondersteun. Die berekende LC50 van 882.78 ug.g" vir koperoksichloried en 519.40 ug.g" VIr koper was ekologies relevant indien 'n veiligheidsfaktor van 10 toegepas is. NRRT se ekologiese relevansie is bevestig deur dit te vergelyk met response wat in die veldtoetse waargeneem is. Deur bioevalueringseksperimente is bevind dat gewigsverlies en mortaliteit van A. caliginosa beduidend hoër was in koperoksichloried gekontamineerde grond as in die grasveld- (kontrole) en wingerdgronde. Veranderinge in biomassa en mortalitiet was aanduidend van populasieresponse soos waargeneem in die veldstudies en kan dus as ekologies relevante eindpunte beskou word. Tonnelaktiwiteit van A. caliginosa was beduidend (p<0.05) laer in wingerd- en koperoksichloried gekontamineerde grond as in grasveldgrond. Dieselfde is gevind in die grondvermydingstoetse waar A. caliginosa wingerd- en koperoksichloried gekontamineerde grond vermy het. Dit kan dus afgelei dat tonnelaktiwiteit en grondvermyding ook ekologies bruikbare eindpunte is aangesien dit verband hou met populasieresponse soos waargeneem in die veldstudies. Hierdie studie het getoon dat die herhaalde gebruik van koperoksichloried 'n nadelige invloed kan hê op erdwurmbevolkings. In die lig van die belangrike rol wat erdwurms en ander grondorganismes speel in grondvrugbaarheid kan die oormatige gebruik van hierdie fungisied ernstige implikasies inhou vir volhoubare benutting van landbougronde. Die gebruik van biomerkers en ander ekotoksikologiese eindpunte kan egter as vroeë waarskuwingsmetode dien dat die grondorganismes onder omgewingstres verkeer.
399

MODIFICATION OF AN EXISTING BENTHAL MODEL FOR PAPER MILL WASTES.

Bauer, Elizabeth Nanette. January 1985 (has links)
No description available.
400

Mine water geochemistry and management : two case studies and a new treatment method

Love, David 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Mine water, that is all forms of water associated with and affected by mining operations is probably the largest area of concern in the environmental geology of mining. This study looks at the inter-relationship between mine water geochemistry and mine water management. The objectives of this study are: 1. To examine major geochemical processes influencing mine water; 2. To apply new national water and environmental legislation to the mining industry and discover how mine water management will be regulated; 3. To examine the approach of Integrated Catchment Management, and discover how this approach can be applied to the mining industry; 4. To conduct two case studies, where environmental geochemistry, general geochemistry and multivariate analyses are used as tools to investigate groundwater contamination problems in mining areas, and therefore suggest mine water management interventions; and 5. To, considering mine water problems discovered in the case studies, develop a newly-patented chemical treatment method for possible application in the mining industry. The changing legal framework - principally the implementation of the National Water Act (Act No 36 of 1998) and the National Environmental Management Act (Act No 107 of 1998) - is leading to the responsibilities of a mine becoming substantially clearer, and responsibilities which in the past could have been ignored until public outcry will now be difficult to escape. Two case studies are investigated. In both cases, general geochemistry and hydrogeochemistry, coupled with factor analysis are used to determine the major signatures in groundwater chemistry and the major sources of contamination. On the basis of this, management interventions are suggested. In the first case study, Sishen Iron Ore Mine of the Northern Cape, three signatures are identified in the groundwater: a clean dolomitic water signature, and a contamination signature from the mine and one from agriculture. The extent of nitrate and diesel contamination is shown to be related to agriculture, the use of explosives and to mine workshops and depots. Surface water controls may help reduce these problems. In the second case study, West Driefontein Gold Mine of the Far West Rand, two signatures are identified in the groundwater: a clean dolomitic water signature and a signature relating to contamination from the mine. Cluster analysis is used to suggest three groundwater zones, the chemistry of one being fairly clean dolomitic aquifer, the chemistry of the second affected by the mine and the chemistry of the third affected by granites. Contamination is shown to be related to mining operations, especially the slimes dams, and agriculture. Rehabilitation of dams and dumps, as well as surface water controls may help reduce these problems. Considering mine water problems discovered in the case studies, a newly-patented chemical treatment method is examined and tested for possible application in the mining industry. It is shown to be extremely effective for the removal of calcium from water, but less effective for the removal of iron and manganese. More broadly, this study shows the inter-dependence between mine water geochemistry and mine water management, and the need to be multi-disciplinary in approach. / AFRIKAANSE OPSOMMING: Mynwater, dit is aile soorte water wat geaffekteer en geassosieer word met mynbou bedrywighede, is moontlik die grootste rede tot kommer in omgewingsgeologie van mynbou. Hierdie studie stel ondersoek in na die verhouding tussen mynwater geochemie en mynwater bestuur. Die doelwitte van die studie is soos volg: 1. Om die hoof geochemiese prosesse te ondersoek wat mynwater beinvloed: 2. Om die nuwe nasionale water- en omgewingswette toe te pas op die mynboubedryf en te ondersoek hoe die bestuur van mynwater gereguleer sal word; 3. Om die benadering van Gerntegreerde Opvangs Bestuur ("Integrated Catchment Managemement") te ondersoek, en te ondersoek hoe hierdie benadering op die mynbou industrie toegepas kan word' 4. Om twee gevallestudies te doen, waar omgewingsgeochemie, algemene geochemie en multivariant analise gebruik word as middels om grondwater besoedeling in mynbougebiede te ondersoek, en daarvolgens om mynwater bestuurswysigings voor te stel; en 5. Om, nemende in ag die mynwater probleme wat ontdek is in die gevallestudies, 'n nuutgepatenteerde chemiese behandelingsmetode, vir moontlike toepassing in die mynbou industrie, te ontwikkel. Die veranderende regtelike raamwerk - hoofsaaklik die implementering van die Nasionale Waterwet (Wet No. 36 van 1998) en die Nasionale Omgewingsbestuur Wet (Wet No.1 07 van 1998) - lei daartoe dat 'n myn verantwoordelik moet wees om opmerklik skoner te word, verantwoordelikhede wat in die verlede maklik gergnoreer kon word maar wat nou te moeilik is om te ignoreer as gevolg van publieke uitroepe. Twee gevalle is ondersoek. In be ide studies word algemene geochemie en hidrogechemie, saam met faktoranalise, gebruik om die hoof kenmerke te bepaal in grondwaterchemie en die hoof bronne van besoedeling. Deur dit as basis te gebruik word bestuurswysigings voorgestel. In die eerste gevallestudie, Sishen Ystererts Myn in die Noordkaap, is drie kenmerkende samestellings qeidentitiseer in die grondwater: 'n skoon dolomitiese samestelling, en een elk van 'n myn en landbou gekontamineerde samestelling. Die omvang van nitraat en diesel kontaminasie word aangedui as geassosieerd met landbou, die gebruik van plofstowwe, mynwerkswinkels en depots. Oppervlak waterbeheer mag help om hierdie probleme te beheer. In die tweede gevallestudie, Wes Driefontein Goudmyn in die Ver Wesrand, is twee kenmerkende samestellings in die grondwater gerdentifiseer: 'n skoon dolomitiese samestelling en 'n samestelling geassosieer met kontaminasie van die myn. "Cluster" analise is gebruik om drie grondwatersones te identifiseer, die eerste een se chemie stem redelik ooreen met 'n skoon akwifer, die tweede een se chemie is bernvloed deur die myn en die derde se chernie is deur granite bemvloed. Kontaminasie word aangedui as geassosieer met mynboubedrywighede, veral die slikdamme, en landbou. Rehabilitasie van damme en afvalhope, asook oppervlak waterbeheer mag help om die probleem te verminder. Deur die mynwater probleme wat in die gevallestudies ontdek is in ag te neem, word 'n nuutgepatenteerde chemiese behandeling ondersoek en getoets vir moontlike toepassing in die mynboubedryf. Dit word aangewys as uiters effektief vir die verwydering van kalsium, maar minder effektief in die verwydering van yster en mangaan. In die algemeen, wys hierdie studie inter-afhanklikheid tussen mynwater geochemie en mynwater bestuur, en 'n behoefte aan 'n rnultidissiplinere benadering.

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