To see the other types of publications on this topic, follow the link: Mine closure and rehabilitation.

Dissertations / Theses on the topic 'Mine closure and rehabilitation'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Mine closure and rehabilitation.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Nel, Johannes Hendrik. "An investigation of mine closure : gold mine case studies on the East Rand in South Africa / J.H. Nel." Thesis, North-West University, 2008. http://hdl.handle.net/10394/4088.

Full text
Abstract:
This research is on mines that struggle to obtain closure from the state departments. The closure process at the footprints of five Tailings Storage Facilities (TSFs) of a South African gold mine was investigated. They are situated in the Germiston, Brakpan, Springs and Nigel suburbs of the East Rand region of Johannesburg. Very limited scientific research has been done in South Africa on the management of mine closure. The most recent performed research was completed at Coal mines and only one was at an underground gold mine. The history of the case studies at a surface gold mine revealed similar problems, as confirmed in previous research, during the interviews with mine management and the review of operational documents. There is a whole array of causes giving rise to the struggle to obtain closure by a mine, that will be subsequently discussed. Major causes are the lack of estimation of closure costs and the lack of a proper Project Life Cycle (PLC) process for closure by mine management. Previous investigations indicated a general shortfall in estimated closure costs, mining operations that are not planned with closure in mind, closure objectives that are not set at all management levels, final land use after mine closure that is not defined properly, residual and latent impacts that are not dealt with, the post-closure period when the final impact will occur that is not defined and a proper risk assessment based on detailed information that is not properly done and communicated. Another cause is that the integrated process of making closure part of the Environmental Management Programme Report (EMPR) process is not followed. The result of not following the correct process is that mines do not obtain closure. Another reason why mines do not obtain closure is because of an underdeveloped mine infrastructure, e.g. tailings facilities, waste rock dumps, shafts and plants that are not constructed in an environmentally friendly way during the operational phases to facilitate closure. Therefore, these structures need to be changed in terms of their topography and growth medium to ensure an improvement in environmental parameters. This will assist in obtaining sustainability and final closure. Significantly more trust fund money than initially estimated during operations needs to be spent to ensure the above change. Specific issues defined from the case studies were the adaptation of the administration of the closure process, the management of risks, especially the differences in opinions, the management of the mine life cycle for closure and involvement of the land owners and Interested and Affected Parties (l&APs). This research was necessary because companies are uncertain and lack the competency to estimate and to correctly spend trust fund money in order to be sure of obtaining closure. This situation threatens the long-term survival of mining-companies by holding assets and profits back until closure is attained. The state departments also have to address the risks and have to rehabilitate the polluted mine sites if companies do not obtain closure. A proper PLC to facilitate closure was compiled from the above-mentioned data. An important fact to bear in mind is that the activities within the life cycle depend on one another. Therefore, when one activity is disregarded or not properly performed, it will influence the outcome of the remaining activities. The methodology of the research was as follows: Categories to evaluate the closure process of the selected case studies were determined from the project life cycle and the management principles of the literature review. Thereafter a questionnaire was developed from these categories. The questionnaire was subsequently used to guide interviews. After the interviews these categories and findings from the questionnaire were combined and summarised into key findings. The key findings of the research were: • The driving force behind obtaining closure must shift from the State Departments to the mining companies. They must realise there is an opportunity during the closure process to make money and to minimise their long-term liability. The mining company must thus drive the closure process to obtain environmental sustainability. • The gold mines do have problems in terms of cost estimation and trust fund expenditure at their TSF footprints during the closure process. The reasons were a mismanagement of the closure process and making use of a limited information system to make decisions. • A proper closure process does exist, but it can be improved to ensure all interested and affected parties have the same expectations from closure. • There are many activities in the closure process flow diagram which were not properly attended to according to the case studies. • A conceptual closure plan and a draft rehabilitation plan with broad objectives, policies and strategies with detailed descriptions were not compiled during the operational phase, because limited scientific monitoring information was gathered to do a proper risk assessment and some l&APs consultation was done mainly with the material and land owners on a one on one basis. From these key findings the following recommendations could be formulated: • Any mining operation should conduct a closure audit at least every second year and before mining activities change. • A searchable record keeping system must be established to keep track of the closure life cycle development. • Detailed conceptual and final closure plans need to capture the data from the audits and record keeping system. • A communication forum with company management and environmental specialists needs to be established.
Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2009.
APA, Harvard, Vancouver, ISO, and other styles
2

Nene, Thami Wellington. "An analysis of the appropriateness of statutory financial security mechanisms for mine closure and rehabilitation in South Africa." Diss., University of Pretoria, 2019. http://hdl.handle.net/2263/76744.

Full text
Abstract:
A lot of mine were left abandoned, unrehabilitated or unclosed prior to the introduction National Environmental management Act 107 of 1998 and most did not have plans for rehabilitation or mine closure. The law requires that no exploration or production operations may commence unless financial provision has been made that is guaranteeing the availability of sufficient fund. planning is a prerequisite in the early development planning phase and must continue throughout the mine life cycle and closure phase. The financial provisions must be maintained for the duration of the life of the mine until closure when the closure certificate is issued. The financial provision is critical in ensuring that environmental liabilities for rehabilitation and closure are addressed. The purpose thereof is to mitigate the negative impacts of mining operations on the environment. This paper will investigate financial provisions system which is currently in use in South Africa from the financial security methods employed, the setting up, determination, quantification as well as general rules applicable thereto. The surveys undertaken in this regard and records held by the DMR will be relied on. When mine operations stop, a closure certificate must be issued to serve as proof that the plans relating to reclamation and closure have been complied with. The effect of a closure certificate exonerates the holder of such right from any residual or latent environmental liabilities. The paper will further look into the reasons and barriers to proper mine closure. The overall SA legislative framework for environmental liability relating to closure and rehabilitation generally conforms with international expectations. This paper examines the principal legislation and in particular the 2015 proposed regulations for securing financial provision for environmental liabilities. The main objectives of the research were to evaluate whether the current financial provision systems are appropriate in guaranteeing mine rehabilitation and closure. Moreover, whether they can realistically alter the legacy inherited from past abandoned or unclosed mines. Lastly, examination of the correlation between closure certificate and financial provision in relation to mine closure. Findings indicate that money set aside as financial provision for environmental liabilities is not being spent by the state. The law is clear which steps mine companies must take for rehabilitation and closure of new and old mine sites including legacy abandoned sites. The law is only as good as its implementation and enforcement. The Success of any financial surety instrument depends on the care, effort put into setting it up, managing it and meticulous calculation. Most will work if they are done properly.
Mini Dissertation (LLM)--University of Pretoria, 2019.
Public Law
LLM
Unrestricted
APA, Harvard, Vancouver, ISO, and other styles
3

Weyer, Vanessa Derryn. "Surface-strip coal mine rehabilitation risk assessment : the development of an integrated rehabilitation risk assessment model for use in South Africa and Australia." Thesis, University of Pretoria, 2020. http://hdl.handle.net/2263/77899.

Full text
Abstract:
Surface-strip coal mine rehabilitation planning in South Africa and Australia is immature. Rehabilitation risk assessment, despite being advocated by leading practice guidelines and in some instances by legislation, is conducted with minimum requirements often met by rehabilitation professionals. Specialist data is gathered during mine approval and for the environmental impact assessment process. However, the focus of this is toward assessing mining impacts and not for rehabilitation risk assessment. Quantitative, integrated, multi-disciplinary rehabilitation risk assessment is seldom undertaken. This thesis provides a methodology towards the development of a quantitative, integrative, multi-disciplinary rehabilitation risk assessment model. Its purpose being to 'profile' surface-strip coal mine sites, in terms of their rehabilitation risk and potential for rehabilitation failure, from the outset of mine operations, with adjustments possible progressively during mine operations. The methodology was developed by first reviewing techniques suitable for the development of the model, as well as techniques developed by others. Bayesian networks (BN) were found to be the most suited. A R2AIN framework was then provided as a process towards developing several BN risk event models that can amalgamate to form a synthesis rehabilitation risk assessment model. A case study soil compaction BN model was used to demonstrate the framework in South Africa and Australia. The case study showed that it is possible to integrate and quantify rehabilitation risk, and most importantly to segregate risk into discrete contributing multidisciplines for analysis. Risk percentages can be calculated per multi-discipline, per mine phase, per site, to aid site risk ‘profiling’. It is recommended that further risk event BN models be prioritised for development and that a rehabilitation risk assessment model be developed to synthesise these into one model. This will require continuous improvements in the method, to build confidence, including extensive risk event and synthesis BN model evaluation and testing; improved BN input node states and values; and simplification of the conditional probability table construction method. Adaptation to other mining types, development activities and other regions should be investigated, as well as spatial linkages to geographic information systems. This research contribution improves upfront mine rehabilitation planning and decision making, providing improved tools and techniques than what currently exist.
Thesis (PhD)--University of Pretoria, 2020.
Geography, Geoinformatics and Meteorology
PhD
Unrestricted
APA, Harvard, Vancouver, ISO, and other styles
4

Haagner, Adrian Sigmund Harold. "The role of vegetation in characterising landscape function on rehabilitating gold tailings / A.S.H. Haagner." Thesis, North-West University, 2008. http://hdl.handle.net/10394/3717.

Full text
Abstract:
Gold mine waste poses a significant challenge for rehabilitation practitioners and can negatively impact on soil, air, surface water and groundwater quality. This, in turn, can affect the environmental quality of humans and other biota in nearby settlements and surrounding ecosystems. All mines are required to have a plan in place to impede or mitigate these environmental impacts and to ensure that all legislation is complied with to apply for closure. Site closure is the eventual goal of all mine residue complexes, as it is the stage at which a company becomes released from all legal and financial liability. The South African legislation is comprehensive and essentially requires that all latent and residual environmental impacts are addressed and that an end land-use designation is put in place that conforms to the principles of sustainable development. The Chemwes Tailings Storage Facility complex near Stilfontein was monitored to provide a strategic assessment of the state of the rehabilitation, and to provide recommendations for the successful remediation of problem sites. A combination of vegetation sampling, landscape function assessments and substrate chemical analyses were conducted to gain a predictive understanding of rehabilitation progress. The monitoring was conducted over two years across a chronosequence of rehabilitating sites from tailings dam slopes and an adjacent spillage site. An undisturbed grassland and a starter-wall served as reference sites. The data were first analysed independently and then by making use of multivariate data ordinations. This allowed for holistic investigations of the relationships between sites, substrate chemistry, vegetation composition and landscape function. The results showed that the tailings dams had a distinctly different suite of vegetation from the reference sites, but had no statistically significant differences in composition across the rehabilitating chronosequence. There were positive correlations between rehabilitation site age and landscape function indices, suggesting that some aspects of ecosystem development were occurring over time. In some sites, deterioration in the substrate quality as a growth medium was observed with increases in acidity and salinity. This was most likely caused by pyrite oxidation in the tailings and the high concentrations of free salts. The increasing acidity and salinity resulted in vegetation senescence and declines in landscape function. However, those sites that possessed higher landscape function appeared to have the ecosystem processes in place that temporarily suppressed negative chemical changes. Whilst this was encouraging,the rehabilitation chronosequence had not yet proven the self-sustainability that it would require for closure purposes. Further monitoring would be required over time. The sustainability of the rehabilitating chronosequence was brought into question by the high acid-forming potential of the tailings growth medium. Concerns were also raised over the ability of the established vegetation cover to persist under conditions of increasing stress and disturbance. Furthermore, the land-use capabilities of the sites are limited by current rehabilitation procedures and various recommendations were made to rectify this. A more streamlined monitoring framework for the tailings complex was also proposed. The contribution of this work lies in its holistic integration of monitoring techniques and the meaningful analysis of ecosystem function, an aspect largely ignored in minesite rehabilitation.
Thesis (M.Sc. (Environmental Sciences and Management))--North-West University, Potchefstroom Campus, 2009.
APA, Harvard, Vancouver, ISO, and other styles
5

De, Jager A. J. (Albertus Johannes). "Generic model for mine closure." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/49679.

Full text
Abstract:
Thesis (MBA)--Stellenbosch University, 2000.
During the last five years, successful mine closure has become one of Iscor Coal Business primary strategic focus areas. Three Iscor Coalmines are currently in different stages of closure, i.e. North Field, Hlobane and Dumacol and the demand on management time spent on this issue is increasing. The changing legal environment, especially issues concerning rehabilitation and mine closure, demands that every company must take full responsibility for any detrimental effect that their operations may have on the environment. This study concerns itself with establishing a generic procedure for mine closure. The interface with all stakeholders, external and internal, is considered. The primary focus areas are determined and the most important issues within each area are discussed in such a way that operational managers and strategists could use it as base knowledge for future closures. Applying the model to an actual closure process, i.e. the closure of Durnacol Coalmine, tested the validity of the model and it was verified that the process could be used as a base for future reference.
APA, Harvard, Vancouver, ISO, and other styles
6

Xavier, André Moura. "Socio-Economic Mine Closure (SEMC) framework : a comprehensive approach for addressing the socio-economic challenges of mine closure." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45595.

Full text
Abstract:
This thesis seeks to investigate the initiatives that address the socio-economic implications of mine closure that have been implemented by three mining companies which are located in Mongolia, Argentina and Canada. It further addresses the perceptions of stakeholders, specifically community members, local government representatives and mining company employees regarding the initiatives that have been implemented by three mining companies. Additionally, the research examines six mining industry-related frameworks/guidelines, and explores the ways in which these documents interpret the socio-economics of mine closure. Finally, this thesis introduces and evaluates the Socio-Economic Mine Closure (SEMC) Framework, which was originally developed as part of this PhD investigation. There are 10 elements in the Framework: Policy, Presence, Participation, Planning, Performance, Promotion, Perseverance, Patience, Passion, and Personality. The SEMC Framework is assessed in multiple ways: a) against the current literature on mine closure; b) through an online survey in which 151 experts were invited to provide feedback on the elements and sub-element constituents of the Framework and c) by its utility in constructing the fieldwork survey and the feedback of survey participants indicating the appropriateness of the framework. The study indicates that it would be relevant, timely and appropriate for the mining industry to introduce, discuss and adopt the proposed SEMC Framework. The case study analyses, all of which employed interviews, group sessions, and distribution of survey material as part of their methodological approaches, reveal that each case has unique characteristics and that all are context-based. The case studies also indicate that all three situations reveal the presence of some common issues. For instance, the results of the study suggest that, in all three cases, communication levels need to be improved and augmented. An important finding of the overall study concerns the element Personality within the SEMC Framework. Although in both the online survey and in the survey distributed to study participants, this element was ranked as one of low importance, through the interviews, group sessions and researcher observations it became clear that the Personality of the company community liaison does play a significant role in maintaining and fostering relationships between mining companies and local stakeholders.
APA, Harvard, Vancouver, ISO, and other styles
7

Unver, B. "Closure in longwall access roadways." Thesis, University of Nottingham, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384696.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Schmidt, Anel. "Strip-mine rehabilitation in Namaqualand." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/53068.

Full text
Abstract:
Thesis (MScFor)--Stellenbosch University, 2002.
ENGLISH ABSTRACT: Namaqualand has a very unusual diversity of plant life, with many endemic plant species. The fundamental question of this thesis is how this system, damaged by strip-mining activities, can be rehabilitated. The aim was to base the rehabilitation methods on ecological processes. In order to answer this question an overview of the relevant literature was needed in order to identify possible research needs and also to evaluate the work that has been done in the field of strip-mine rehabilitation in arid areas. An understanding of community and ecosystem dynamics would help to establish aims and methods for site-specific rehabilitation. In Namaqualand, South Africa, there is also a need for experimentation to establish which of the many factors is most limiting to long-term ecosystem recovery. It is important to have a good knowledge of the successional processes and disturbance history of the land which needs to be rehabilitated. The vegetation on unmined areas and mined areas of different ages and treatments after mining, were sampled. It was shown that some areas could be expected to show a large degree of recovery in the space of a few years, whilst others would show little or no recovery over a period of decades. It is important to recognise rehabilitation as a gradual process that takes place at different rates in different areas and in different years. The planting of Atriplex nummularia and sowing of Atriplex semibaccata did not facilitate the return of indigenous, perennial species, but rather seem to inhibit their return. In view of the importance of topsoil in terms of the fertility of the soil and the seed bank present in the topsoil, the influence of topsoil removal and stockpiling due to strip-mining activities were tested. The soil fertility was tested by means of radish bioassays and soil laboratory analysis, whilst species diversity and richness were tested with seedling emergence trials. As expected a higher plant species diversity was found on the unmined soils and radishes grew larger on these soils. The topsoil deteriorated in terms of plant species richness, diversity and soil fertility whilst it was stockpiled. Direct replacement of topsoil would ensure a planting medium closer to the pre-disturbance level that could lead to fairly rapid and successful recolonization of the mined area. Successful plant recruitment also depends on the microsites to which seeds are dispersed. The effect that different microsites had on seed germination, seedling growth and survival was tested. It was found that micro catchments always yielded the highest numbers. The establishment and survival of seedlings in the other microsite types (under single shrubs, under clumped shrubs and in the open) varied, depending on the amount of rainfall received in the particular year. Lastly, I experimented with the translocation of three local, indigenous, succulent plant species. These plants were transplanted either in clumps of three together or alone, since I hypothesized that planting them together would facilitate their survival. However, it was found that it depended largely on the morphology of the plant and the amount of rainfall received in a particular year, whether these plants will compete with each other for limiting resources or facilitate each other's survival. The thesis contributes to the understanding of vegetation dynamics in the Succulent Karoo after strip-mining has taken place. Guidelines are provided based on ecological processes, for strip-mine rehabilitation in the Succulent Karoo.
AFRIKAANSE OPSOMMING: Namakwaland is bekend vir sy ongewone diversiteit van plante, met baie endemiese spesies. Die fundamentele vraag wat deur hierdie tesis gevra word is hoe hierdie sisteem, wat beskadig is deur oppervlak mynbou, gerehabiliteer kan word. Die doel is om die rehabilitasie metodes te baseer op ekologiese prosesse. 'n Oorsig van die relevante literatuur was nodig om moontlike areas van verdere navorsing te identifiseer en ook die navorsing wat reeds gedoen is oor rehabilitasie van oppervlak myne in ariede gebiede, te evalueer. 'n Goeie begrip van gemeenskap en ekosisteem dinamika sal help om doelwitte en metodes daar te stel vir die rehabilitasie van spesifieke areas. Dit is ook nodig om in Namakwaland, Suid -Afrika, uit te vind watter van die baie faktore, die lang-termyn herstel van 'n ekosisteem, die meeste verhinder. Dit is baie belangrik om In goeie kennis te hê van die versteurings geskiedenis van die area wat gerehabiliteer moet word, asook die suksessionele prosesse wat werksaam is. Plantegroei van areas wat op verskillende tye gemyn en verskillend behandel is, asook ongemynde areas is ondersoek. Sekere areas het In groot mate van herstel gewys in 'n tydperk van 'n paar jaar, terwyl ander, min of geen hersteloor 'n periode van dekades getoon het nie. Dit is belangrik om rehabilitasie as 'n geleidelike proses te sien, wat teen verskillende tempos plaasvind tydens verskillende jare en in verskillende areas. Daar is bevind dat die plant van Atriplex nummularia asook die saai van Atriplex semibaccata nie die terugkeer van inheemse, meerjarige spesies bevoordeel nie, maar dit eerder inhibeer. Aangesien die bo-grond so belangrik is in terme van die grondvrugbaarheid en ook die saadbank wat teenwoordig is, word die invloed van die verwydering en opberging van die bogrond getoets. Die grondvrugbaarheid was bepaal deur groei-toetse op radyse en laboratorium analise op die grond te doen. Die plant spesie diversiteit en rykheid was bepaal met In saad ontkieming studie. In ooreenstemming met die verwagte uitkoms, was die plant spesie diversiteit hoër op die ongemynde bo-grond en die radyse het groter geword op dieselfde grond. Dit kom voor asof die plant spesie diversiteit en rykheid, asook die grond vrugbaarheid afneem met tyd wat die bo-grond geberg word. Die direkte verspreiding van die bo-grond nadat dit verwyder is, sal In medium vir die plante verseker wat nader is aan die vlak voordat die grond versteur is. Dit sal oak sorg vir redelike vinnige en suksesvolle terugkoms van plante op die gemynde grond. Die suksesvolle vestiging van plante hang ook af van die mikro areas (klein areas in terme van die grootte van 'n saad, wat In eie mikro-klimaat vorm), waarna saad versprei word. Die effek van sulke mikro-gebiede op die ontkieming van saad, die groei van die saailinge en die oorlewing van die saailinge was bepaal. Mikro-water- opvanggebiede het in al drie bogenoemde gevalle die hoogste syfers getoon. Die vestiging en oorlewing van saailinge in die ander mikro-gebiede (die area onder enkel struike, die area onder groepe struike en oop areas) het gevarieer afhangend van die hoeveelheid reënval wat ontvang is in die spesifieke jaar. Laastens, is daar ge-eksperimenteer met die oorplant van drie plaaslike, inheemse, sukkulente spesies. Hierdie plante was alleen geplant of in groepies van drie, bymekaar. Die hipotese was dat huloorlewingskanse beter sal wees as hulle saam geplant word. Dit was egter bevind dat die hoeveelheid reënval in 'n spesifieke jaar en die morfologie van die plant, bepaal of hulle sal kompeteer vir die beperkte bronne en of hulle deur saam te groei huloorlewingskanse sal verhoog. Hierdie tesis dra by tot die verstaan van die plantegroei dinamika in die Sukkulente Karoo nadat oppervlak mynbou plaasgevind het. Riglyne vir die rehabilitasie van oppervlak myne, gebasseer op ekologiese prosesse, word ook voorgestel.
APA, Harvard, Vancouver, ISO, and other styles
9

Reynolds, Christopher David. "The effects of coal mine closure on macroinvertebrate communities." Thesis, Nottingham Trent University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341279.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Shen, Boxi. "Study on financial assurance and closure cost for mine reclamation." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/60171.

Full text
Abstract:
Financial assurance for mine closure has been widely adopted by governments and companies internationally. Concern has grown in and around the global mining and mineral processing industry over potential risks associated with insufficient funding for mine closure. The motivation of this research is to review financial assurance information from several jurisdictions and to quantitatively assess closure cost for a specific example. This research address the following four objectives: 1. To carry out a literature review on financial assurance for mine reclamation. 2. To compare present regulations and policies on financial assurance for mine closure in Canada, United States and Western Australia. 3. To identify expectations for different types of mining. 4. To develop the closure approaches and apply a method to estimate and calculate the closure cost for a mine site. Main research results are as follow: a. Significant reclamation financial assurance information is highlighted, and the expectations of various stakeholder are identified for different types of mines in various jurisdictions across the world. b. Mine reclamation laws in selected jurisdictions of the Canada, United States, Western Australia have some differences and similarities in regulating agency, closure legislation, guidelines and other aspects. Regulations and policies on financial assurance for mine reclamation in the United States and Canada can be classified into prescriptive and performance-based approaches. The performance-based approach is preferred by mining companies for mine reclamation regulations. c. Developing a mine closure cost estimate requires an understanding of the site-specific closure requirements and available software can be used to perform the closure cost estimates. This study applies the Sherpa software to calculate the closure cost of a conceptual gold mine near Winnemucca, Humboldt County, Nevada. ArcGIS Software is used for calculating the size of each small surface water catchment areas for this mine. The final cost estimate for the total closure cost for the gold mine near Winnemucca, Humboldt County, Nevada is $32,417,400 including $22,574,400 direct cost and $9,843,000 of indirect cost. Considering the Gross Receipt Tax of $677,200, the total financial assurance for this project is $33,094,600. The total overhead costs account for 30.4% of the direct project costs.
Applied Science, Faculty of
Mining Engineering, Keevil Institute of
Graduate
APA, Harvard, Vancouver, ISO, and other styles
11

Sherwood, Julia Merryn. "Modelling minewater flow and quality changes after coalfield closure." Thesis, University of Newcastle Upon Tyne, 1997. http://hdl.handle.net/10443/314.

Full text
Abstract:
The changes that have taken place in the British Coal Industry over the last five years have meant that in many coalfileds the last deep mines have closed. When a coalfield is abandoned and dewatering ceases, groundwater levels rebound, threatening surface waters with polluting discharges. However, the sparse data sets available limit modelling with existing techniques. A lumped parameter model GRAM (Groundater Rebound in Abandoned Mineworkings) has been developed. This model conceptualises a coalfield as a group of 'ponds'. Each pond is an area of the coalfield that has been extensively worked and can be considered as a single hydraulic unit. The ponds are connected by pipes which represent major inter-connecting roadways along which flow is assumed to be turbulent. Discharge to the surface is also represented using pipes. Flow through the pipes can be calculated using the Prandtl and Nikuradse of the Colebrook-White pipeflow equations. The storage coefficient can vary vertically to represent both worked Coal Measures and the intervening unworked strata. GRAM is able to predict the timing and volume of discahrges. An iron component gives an indication of the water quality evolution of the discahrges. Monte Carlo simulation allows the variables that have most error in their estimation to be represented by probability distributions. The Dysart-Leven Coalfield in eastern Fife, Scotland has not been mined since 1985. However, dewatering has continued to protect the workings in the Frances Colliery. In 1994 British Coal decided the Frances would never reopen, there is therfore no longer a need to continue dewatering. GRAM has been used to produce estimates of the quantity, timing and location of dischargges from the Dysart-Leven Coalfield should pumping cease. MODFLOW has also been applied to the coalfield with less success. Water quality modelling was also attempted using GRAM's iron component, however, conclusive results will not be obtained until the three variables over which ther is most uncertainty have been calibrated against existing discharges.
APA, Harvard, Vancouver, ISO, and other styles
12

Mackenzie, Andrew G. "A socio-economic impact assessment of the future closure of a diamond mine in Namaqualand, South Africa : planning for mine closure a decade in advance." Master's thesis, University of Cape Town, 1992. http://hdl.handle.net/11427/17326.

Full text
Abstract:
Bibliography: pages 56-7.
De Beers Namaqualand Mines (DBNM) have appointed the Environmental Evaluation Unit to undertake an impact assessment of mine closure. According to recent estimates DBNM anticipate that their diamond mining operations in Namaqualand will have to be closed in approximately ten years time. DBNM requested that the study focus on the socio-economic implications of mine closure within the regional context of Namaqualand and not the broader context of South Africa. It is anticipated that the results and recommendations of the study will be used by DBNM in planning for mine closure. The aims and objectives of the study are: 1) To assess the socio-economic consequences of future mine closure. 2) To recommend actions that will mitigate the impacts of mine closure. The aims and objectives of this report are to: 1) Fulfil the academic requirements of the degree. 2) Assess and evaluate information collected during the data collection phase of this project (contained in the Baseline Information Report) and to present these findings clearly and concisely, highlighting significant impacts and options for mitigation. 3) To communicate these findings in a way as would make them useful to both the client as the decision-maker and the interested and affected parties.
APA, Harvard, Vancouver, ISO, and other styles
13

Toni. "Economic model of mine closure and its potential for economic transformation." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2015. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-162978.

Full text
Abstract:
In Indonesia, the various mining commodities and the amount of resources and reserves are promising, as evidence there are numerous large-scale mining companies and small-scale mines in operation. In 2014 there were 41 companies that held the CoW (mineral contract of work) and 13 companies active in production; and 76 CCoW (coal contract of work) holders, and 57 companies active in production. As well as this, there are more than a thousand small-scale mining companies active for mining commodities. However, mining commodities provide a resource that is not renewable. This will potentially lead to prolonged problems when mining companies do not adhere to good mining practices, particularly in the closing stages of the mine. Mine closure is the final stage in the process of mining activity. In certain circumstances, closure activities can take a long time and of course can have huge costs. In fact, at this stage, the company is no longer making profit, only incurring costs for the project closure. To prevent problems that may arise after the mine is closed, such as abandoned post-mining land, and the bankruptcy of the company at the end of mining operations, etc., then through specific rules, ie rules of the Minister of Energy and Mineral Resources No. 18 of 2008, the mining company in Indonesia must provide a certain amount of money as a financial guarantee to finance the planned closure project; it must be approved by the government before entering this phase. However, problems are encountered in practice. The government may become overloaded because they have to quickly make a decision on the closure plan submitted by the company. So a tool is needed that can be used to assess the feasibility as soon as the mine closure plan is proposed by a company, these tools can provide an overview and a variety of options for decision making. In this dissertation methodology was developed to create a systems dynamic model of mine closure. The model developed can be applied to a variety of mining methods and for various mining commodities. The model can be used to determine the closure costs, to choose the closure project-financing scenario, and up to micro and macro economic analysis of mining activities in the region. In the case studies conducted in this dissertation, the best scenario of the mine closure planning is to include the everlasting fund in the form of time deposits, and convert the post-mining land for agriculture. The amount of deposit money is about USD 358,986,500 should be spare at the end of mine production, and the total of mine closure cost to be approximately USD 440,757,384. Agriculture, the economic sector as a substitute for the mining sector, the added value to the GRDP (Gross Regional Domestic Product) is about 0.25 % / a for the province, and 1.68 % for the regency, but the contribution of the mining sector to GRDP was 30% / a at province scale, and 90% / a at regency scale. So that the substitution value is less significant to GRDP growth. However, this scenario is the best scenario among others, due to consideration is the certainty of ecological and economic sustainability. it is the best goal of corporate social responsibility to the environment in the post- mining land.
APA, Harvard, Vancouver, ISO, and other styles
14

Collins, Benjamin C. "Mine closure planning with First Nations communities : the Stk'emlupsemc te Secwepemc Nation and the New Afton Mine." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54759.

Full text
Abstract:
The goal of this research is to understand how the traditional knowledge of the Stk’emlupsemc te Secwepemc Nation can be used to improve reclamation and closure planning of the New Afton mine. Furthermore, this research will provide insight into consultation with First Nation communities for closure and reclamation planning. The New Afton Mine site, located ten kilometers west of Kamloops, BC is on the traditional territory of the Tk’emlúps te Secwepemc and Skeetchestn Indian Bands. The application of traditional knowledge for closure is a relatively new field. As such, the application of the findings of this research are at a conceptual level. Interviews with traditional knowledge keepers were conducted to understand the relationship between plant life, wildlife, water sources and the traditional use pattern in the area. Site visits to both the Stk’emlupsemc te Secwepemc Nation and New Afton Mine site have taken place during this research study. Visits to the New Afton property focused on determining and understanding the different areas of disturbance. Visits with the Stk’emlupsemc te Secwepemc members were aimed at engaging, recognizing, and understanding their objectives for the long term post-closure use of the mine site. This research found an extremely strong connection between the community’s culture and natural environment. In addition, hunting, fishing, medicinal and nutritional plant gathering were considered as the key traditional land uses in the area. The New Afton Mine was known as an old stop-over ground for travelers in the region. Concerns relating to the impacts of tailings and possible contaminants to the environment (water, wildlife and plant life) were indicated. Reclaiming the land to a natural state was outlined as the most desirable outcome for closure. The technical constraints of the property were also discussed (subsidence zones, semi-arid conditions, etc.) and how the property, considered as a brownfield development, impacts the closure and reclamation outcomes. Finally, through the interviews and field notes, it was found that successful consultation and collaboration with First Nations communities requires: respect and understanding of the community’s culture and history, well established trust, and an ability to be flexible to the needs of the community.
Applied Science, Faculty of
Mining Engineering, Keevil Institute of
Graduate
APA, Harvard, Vancouver, ISO, and other styles
15

Sherwood, Julia M. "Modelling minewater flow and quality changes after coalfield closure." Boston Spa, U.K. : British Library Document Supply Centre, 1997. http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.363536.

Full text
APA, Harvard, Vancouver, ISO, and other styles
16

Rose, R. "The experience of psychiatric rehabilitation in the wake of ward closure." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/848106/.

Full text
Abstract:
This thesis is presented in three parts. Part one is a review of the literature concerning deinstitutionalisation and the move towards psychiatric care in the community. Studies evaluating the outcomes of psychiatric patients discharged from hospital to community services are discussed. Part two presents a qualitative empirical study which explores the experiences of psychiatric patients in a rehabilitation ward, and the views of staff who work there. The understanding of the rehabilitation process is explored as is the impact of reprovision as a result of ward closure. Part three presents a critical appraisal of the empirical paper, reflecting on theoretical and methodological issues that were raised during the research.
APA, Harvard, Vancouver, ISO, and other styles
17

Keilich, Walter. "Numerical modelling of mining subsidence, upsidence and valley closure using UDEC." School of Civil, Mining & Environmental Engineering - Faculty of Engineering, 2009. http://ro.uow.edu.au/theses/862.

Full text
Abstract:
Ground subsidence due to mining has been the subject of intensive research for several decades, and it remains to be an important topic confronting the mining industry today. In the Southern Coalfield of New South Wales, Australia, there is particular concern about subsidence impacts on incised river valleys – valley closure, upsidence, and the resulting localised loss of surface water under low flow conditions. Most of the reported cases have occurred when the river valley is directly undermined. More importantly, there are a number of cases where closure and upsidence have been reported above unmined coal. These latter events are especially significant as they influence decisions regarding stand-off distances and hence mine layouts and reserve recovery.The deformation of a valley indicates the onset of locally compressive stress conditions concentrated at the base of the valley. Compressive conditions are anticipated when the surface deforms in a sagging mode, for example directly above the longwall extraction; but they are not expected when the surface deforms in a hogging mode at the edge of the extraction as that area is typically in tension. To date, explanations for valley closure under the hogging mode have considered undefined compressive stress redistributions in the horizontal plane, or lateral block movements and displacement along discontinuities generated in the sagging mode. This research is investigating the possibilities of the block movement model and its role in generating compressive stresses at the base of valleys, in the tensile portion of the subsidence profile. The numerical modelling in this research project has demonstrated that the block movement proposal is feasible provided that the curvatures developed are sufficient to allow lateral block movement. Valley closure and the onset of valley base yield are able to be quantified with the possibility of using analytical solutions. To achieve this, a methodology of subsidence prediction using the Distinct Element code UDEC has been developed as an alternative for subsidence modelling and prediction for isolated longwall panels. The numerical models have been validated by comparison with empirical results, observed caving behaviour and analytical solutions, all of which are in good agreement. The techniques developed in the subsidence prediction UDEC models have then been used to develop the conceptual block movement model. The outcomes of this research have vast implications. Firstly, it is shown that valley closure and upsidence is primarily a function of ground curvature. Since the magnitude of curvature is directly related to the magnitude of vertical subsidence there is an opportunity to consider changes in the mine layout as a strategy to reduce valley closure. Secondly, with further research there is the possibility that mining companies can assess potential damage to river valleys based on how close longwall panels approach the river valley in question. This has the added advantage of optimising the required stand off distances to river valley and increasing coal recovery.
APA, Harvard, Vancouver, ISO, and other styles
18

Centeno, Camila Lamonato. "Sistematização de procedimentos para o fechamento temporário de minas de agregados." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/165262.

Full text
Abstract:
O presente trabalho descreve uma metodologia utilizada para a construção de um procedimento padronizado a ser utilizado por técnicos do Departamento Nacional de Produção Mineral (DNPM) para avaliação de solicitação de suspensão temporária do empreendimento por um período determinado. O método está implementado através de um formulário construído para ser aplicado na fiscalização de campo prevista na legislação mineral em caso de solicitação de suspensão das atividades de mineração, inicialmente com proposta de aplicação em minas a céu aberto de agregados. A proposta desenvolvida parte do princípio que a justificativa apresentada pela empresa é satisfatória e que ela entregou todos os documentos previstos na legislação, também de maneira satisfatória e sistematiza itens de caráter atual do empreendimento para classificar de forma padronizada e objetiva o estado atual da unidade solicitante. A metodologia possui a intenção de complementar a análise, torná-la menos subjetiva e confirmar as informações contidas nos documentos entregues. O procedimento também visa que os impactos sejam mitigados e que a área permaneça sob cuidados permanentes do empreendedor, sem agravamento dos passivos, assim como, possibilite a retomada das operações de forma segura.
This work describes a methodology used to construct a standard procedure to be used by technicians of the National Department of Mineral Production (DNPM) to evaluate the request for mining temporary suspension for a certain period. The method is implemented through a form, built to be applied in the field inspection provided for the mineral legislation in case of request for suspension of the mining activities, initially with proposal of application in open cast mines of aggregates. The idea developed assumes that the justification presented by the company is satisfactory and that it showed all documents provided for the legislation, also in a satisfactory manner. It systematizes items of current character to classify in a standardized and objective way the mine that is requesting suspension. The methodology intents to complement the analysis, make it less subjective and confirm the information contained in the submitted documents. The procedure also aims at mitigating the impacts and that the area remains under permanent care and maintenance, without aggravating the liabilities, as well as, enable to return the operations in a safe way.
APA, Harvard, Vancouver, ISO, and other styles
19

Gardiner, Sean Jonathan. "Impacts of mining and mine closure on water quality and the nature of the shallow aquifier, Yandi Iron Ore Mine." Curtin University of Technology, Department of Applied Geology, 2003. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=15728.

Full text
Abstract:
The Hamersley Yandi Iron Ore Mine of Hamersley Iron Pty. Ltd. is located in the Pilbara region, Western Australia, approximately 90km north west of the town of Newman. The iron ore has accumulated in a palaeochannel as an enriched Channel Iron Deposit (CID). Mining in other parts of this palaeochannel has been practised since 1991. Named deposits in the province are, from west to east, Munjina, Pool, Meander, Western, Central, Eastern, Junction and the Billiard deposits.Presently the CID acts as an aquifer and transmits water through its fracture system. It is the main conduit for the regional groundwater. The Water and Rivers Commission of Western Australia considers the groundwater in the alluvial beds of the Weeli Wolli Creek overlying the CID to be a useful resource. The groundwater is currently used for stock watering so the quality should be preserved.Part of the four possible closure plans of the Yandi Mine is to backfill the excavated channel with waste rock from the mining operation. The waste material will consist of the uneconomic grade lateritic pisolite iron ore, together with colluvium and alluvium overburden. The closure plans will also leave behind two pit lakes.The impact of these closure plans vary but each plan will leave pit lakes containing water with high salinity and this may adversely affect the quality of the groundwater downstream of the lakes.The hydraulic conductivity of the shallow aquifer may be impaired by swelling clays found in parts of the waste material. This impact would be reduced if the chosen closure plan was one with hydrogeological flow management.The water quality downstream of the pit lakes will change and the environmental impact on the groundwater will depend on which closure plan is chosen. This thesis suggests a number of options for consideration.
APA, Harvard, Vancouver, ISO, and other styles
20

Short, Robin Vincent. "Using socio-economic impact assessment to plan for mine closure: De Beers Namaqualand Mines proposed closure in ten years time (AD 2002)." Thesis, University of Cape Town, 1992. http://hdl.handle.net/11427/23338.

Full text
APA, Harvard, Vancouver, ISO, and other styles
21

Roberts, Stephen Alexander. "An analysis of stakeholder perceptions regarding the closure of the Highland Valley Copper Mine." Thesis, University of British Columbia, 2005. http://hdl.handle.net/2429/37992.

Full text
Abstract:
The focus of mine closure policies and practice in British Columbia has undergone considerable change since the first closure laws were enacted in the late 1960s. Even though the technical standards for determining what constitutes a successful mine reclamation project have risen considerably over the past three decades, the public’s growing hostility toward the industry suggests that expectations have risen even faster. In response to the public’s rising expectations, the mining industry has begun to develop new policies for integrating sustainable development principles into their closure planning models, but creating a systematic and transparent framework for measuring and reporting actual system performance remains elusive. Sustainable Development Indicators (SDIs) may provide part of the solution, but a problem with many of the proposed indicator systems is that they focus too narrowly on biophysical impacts while neglecting social and economic impacts. Furthermore, most indicator systems were developed by and for experts, thus making them ill-suited for describing system performance from the perspective of those living in the affected communities. To facilitate greater public understanding those charged with developing policies for mine closure and reclamation need to work with stakeholders to develop a set of “sustainability proofs” that simply and effectively communicates to the local community how the company’s reclamation and closure program will assist the community in making the transition to a post-mining economy. This case study of the Highland Valley Copper (HVC) mine presents a framework for identifying these indicators that utilizes a heuristic model to integrate expert advice with local knowledge. Twenty stakeholders were interviewed to determine their perceptions of the quality and focus of HVC’s closure planning and reclamation program to date. Despite the fact that the community’s capacity for effective long-term consultation is limited, the results underscore the fact that local stakeholders fully expect to be involved in preparing the final closure plan. There is a clear preference for a closure plan that would allow another industrial user to assume partial control over the site. Evidence was provided which suggests that aesthetics play an important function for evaluating the effectiveness of HVC’s reclamation program. Finally, the issue of third party liability is seen as an important impediment to any plan to have the site support a follow-on industry. The limitations of the study and future directions for research are also discussed. Key Words: Aesthetics, Community Capacity, Highland Valley Copper mine, Mine Closure and Reclamation Policy, Public Consultation, Sustainable Development Indicators
Applied Science, Faculty of
Mining Engineering, Keevil Institute of
Graduate
APA, Harvard, Vancouver, ISO, and other styles
22

Brearley, Darren. "Developing completion criteria for rehabilitation areas on arid and semi-arid mine sites in Western Australia." Curtin University of Technology, Department of Environmental Biology, 2003. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=13937.

Full text
Abstract:
Continued expansion of the gold and nickel mining industry in Western Australia during recent years has led to disturbance of larger areas and the generation of increasing volumes of waste rock. Mine operators are obligated to rehabilitate all disturbed surfaces and reconstructed landforms, and considerable effort and expense is now applied to the achievement of this objective. Associated with increasing rehabilitation effort is the requirement to accurately judge rehabilitation success through the development of completion criteria. Completion criteria are rehabilitation performance objectives set as conditions of approval for each stage of rehabilitation and for the project as a whole. They provide standards against which the success of rehabilitation can be measured, or more broadly the point at which responsibility for rehabilitation is complete. The current research project tackles the development of completion criteria by investigating ecosystem function within a variety of rehabilitation trials at four mine sites located in arid and semi-arid Western Australia, and also within surrounding 'natural' vegetation complexes undisturbed by mining, termed analogue sites. Six specific objectives were identified as part of the study: 1. To establish an appropriate end point land use for each mine site where field trials were established; 2. To examine long-term ecosystem development through the assessment of revegetation at a variety of rehabilitation sites; 3. To examine functional components within analogue communities and make appropriate comparisons with rehabilitation trials; 4. To record the potential reproductive capacity of revegetation progeny, and determine how this relates to ecosystem function;
5. To provide a better understanding of ecosystem function by investigating the relationship between state factors, interactive controls, and ecosystem processes at rehabilitation and analogue sites; and 6. To develop a methodology for establishing realistic environmental completion criteria at mine sites situated in arid and semi-arid Western Australia. Field trials were established at four mine sites located within three subtly different bioclimatic zones that extend through the arid / semi-arid shrubland belt of Western Australia; Northeastern Goldfields (Granny Smith Gold Mine, Sunrise Dam Gold Mine), Eastern Goldfields (Black Swan Nickel Mine), and Northeastern Wheatbelt (Westonia Gold Mine). 1 The re-establishment of a self-sustaining vegetation cover integrated with the surrounding ecosystem, was the common end land use objective at the four mine sites selected for this study. For three sites located in the Northeastern Goldfields and Eastern Goldfields of Western Australia, sheep were grazed on surrounding rangeland; the fourth site located in the Northeastern Wheatbelt of Western Australia, and was surrounded by Crown Land. 2 To better understand ecosystem function, the dynamic behaviour and interaction of plant biodiversity parameters was monitored regularly at 19 post-mining rehabilitation sites up to 11 years after direct seeding. For functional ecosystems, plant biodiversity parameters changed rapidly during the initial five years after seeding following predictable trends, after which time they remained within a relatively stable range.
The stabilising of parameters over time was identified as a key indicator of rehabilitation success, however the point at which the parameters stabilised was influenced by numerous variables and was difficult to accurately predict. Prolific seed germination resulted in high seedling density during the initial growing season. Plant density then progressively decreased in response to competition, before stabilising within a range approximately five years after seeding. Revegetation cover was typically low during the first growing season, increasing rapidly there after before also stabilising in line with plant density. Maximum species richness was generally achieved during the first and second year when annual Atriplex species were prominent. Perennial Atriplex species established more slowly during the early stages of revegetation development, but eventually replaced the annual component as the dominant taxa. Perennial Maireana species required up to three years before germinating in the field and establishing themselves in the revegetation; in many cases they replaced perennial Atriplex as the prominent taxa. The presence or absence of cyclonic rainfall during the first growing season was a major determinant of the ecosystem trajectory, controlling revegetation structure and composition. The germination and successful establishment of hard seeded species, including Acacia and Senna, was reliant on heavy summer rainfall during the early stages of ecosystem development to break seed dormancy and extend the length of the first growing season. This provided an important competitive advantage against faster growing Atriplex species, which possessed greater drought tolerance.
The intensity of summer rainfall was also beneficial in leaching surface salts from the upper profile and hence, reducing salinity within the rooting zone. In the absence of heavy summer rainfall during the first growing season, the establishment of a low chenopod dominated vegetation cover was favoured, total species richness for the rehabilitation tended to be lower, and the variety of plant life forms was restricted to low and mid stratum shrubs. Increasing water stress resulted in progressively higher rates of local species extinction, with fewer taxa possessing the drought tolerance adaptations required to survive. For established revegetation, cyclonic rainfall increased productivity (as measured by % foliage ground cover) and stimulated the establishment of new taxa, which in many cases were brought in from adjacent unmined vegetation complexes (analogue sites). While the benefits of summer cyclonic rainfall were undoubtedly important to ari and semi-arid ecosystems, the occurrence of drought was also important in buffering the ecosystem against large-scale change by acting as a negative feedback to constrain cumulative productivity. Parent waste rock material varied considerably between rehabilitation sites, affecting the soil resource supply and associated functional components. Extreme salinity was a typical limitation of the rehabilitation medium, reducing the variety of salt tolerant species and favouring annual Atriplex during the early stages of ecosystem development. The cover of annual species present during early stages of ecosystem development contributed to decreasing salinity in the plant rooting zone, by reducing surface temperature and hence capillary rise of salts during summer months.
Annual Atriplex species were replaced by perennial Atriplex in line with decreasing surface salinity. Fundamental to successful revegetation of the post-mining rehabilitation site was the requirement that reconstruction and contouring focus on maximising water retention and reducing salinity within the upper soil profile. Once the initial vegetation community established and plant parameters became relatively stable, change continued to occur, albeit slowly. One factor contributing to this change was the immigration rate of biota from adjacent revegetation or more commonly from surrounding analogue complexes. Linking rehabilitation areas to surrounding functional ecosystems ensured the movement of plants and animals, and ultimately increased the rate of recovery. The sustainability of post-mining rehabilitation was enhanced where these links were established early, allowing for the provision of additional seed and the migration of displaced species. The life cycle pattern of keystone species in the revegetation was found to be an important determinant in long-term sustainability of the plant cover, particularly for chenopod shrublands where one species was typically dominant. The senescence and death of large numbers of a dominant revegetation species together, had the ability to significantly alter the revegetation structure and composition. The impact for rehabilitation where a number of dominant taxa co-exist was less pronounced. Thus it follows that a minimum level of species richness was important to long-term rehabilitation sustainability, as was the development of an age-class structure in the rehabilitation.
The most common disturbances encountered at the rehabilitation trial sites were drought, overgrazing and weed infestation. All three disturbances decreased the plant biodiversity parameters measured. Ecosystem recovery following disturbance was dependent on effective rainfall, but occurred rapidly with plant parameters returning to pre-disturbance levels within one to two growing seasons. The recovery of plant biodiversity parameters followed the same trends identified at functional rehabilitation sites during the initial five years following direct seeding. 3 Assessment of plant biodiversity parameters occurred at 15 analogue sites supporting native vegetation undisturbed by mining. It was anticipated that data from analogue sites could be used as a 'reference' against which to compare developing rehabilitation. However, analogue vegetation complexes were less dynamic in comparison to rehabilitation sites. Minor seasonal changes were recorded for plant biodiversity parameters, but overall annual change was minimal. Significant and sudden changes within analogue communities only occurred following disturbance, such as severe overgrazing, and recovery to pre-disturbance levels was rapid following the removal of the disturbance and return of effective rainfall. A major difference between rehabilitation and analogue sites related to their age. Rehabilitation sites were 'juvenile systems' assessed against a time frame much shorter than had been required for natural processes to achieve the developmental state represented at analogue sites.
Hence, it was important not to model one specific analogue site too closely, but instead model the desired revegetation structure and species composition on a variety of local analogue complexes occurring in parent materials 'matched' closely to those of the rehabilitation site. Data from analogue sites should be utilised extensively during rehabilitation planning, but cautiously when interpreting the rehabilitation outcome. For mine sites in arid and semi-arid Western Australia, the application of specific numeric targets for plant biodiversity parameters as a measure of rehabilitation success was not recommended. A number of factors and controls in the developing ecosystem together determined the rehabilitation outcome. These factors were site and time specific; minor changes in any number of variables led to significantly different rehabilitation outcomes, making them difficult to accurately predict. 4 Quality and germination testing confirmed progeny seed from a number of rehabilitation trials was of similar or higher viability than the maternal seed originally sown. This was further confirmed by field responses at trials in the Northeastern Goldfields one year after the 1994 drought, when elevated plant density was recorded following the return of above average rainfall. The ability of rehabilitation to show an immediate response to rainfall following a seven-month drought, and for vegetation parameters to subsequently recover to pre-disturbance levels within one to two years, provided an indication that the revegetation cover was resilient. The relationship between plant production and rainfall was dependent on a 'carryover' effect between seasons or following drought years, and 'pulses' mediated, for instance, by the amount of seed in the soil store.
The 'reserve' component in and ecosystems was responsible for both the memory of the system between pulses and for its long-term resilience. 6 The analysis of time series data collected from 19 rehabilitation trials emphasized the importance of planning and implementation of best practice techniques to subsequent rehabilitation success, and reinforced the difficulty associated with accurately predicting the final rehabilitation outcome. The large spatial heterogeneity of undisturbed vegetation complexes across the landscape of arid and semi-arid Western Australia, provided the foundation on which site-specific rehabilitation scenarios could be modelled, albeit with caution. The translation of data into useful completion criteria was dependent on the realisation that successful rehabilitation requires the implementation of best practice rehabilitation techniques, as determined by technically prescriptive (design) based standards, as much as the identification of a successful rehabilitation outcome, as determined by performance (outcome) based standards. With this in mind, completion criteria were developed as part of a robust theoretical framework incorporating the larger mine plan, and were not simply based on numbers generated as stand-alone performance standards. The broad methodology generated could be adopted by any mine site across the mining industry, however the criteria and, more specifically, the standards for each criterion should always remain site specific.
The methodology designed for developing completion criteria has been addressed in three stages: 1. Planning, 2. Operational and Monitoring, and 3. Post-Mining Hand-Over. Within each stage three parameters are addressed: 1. Criteria, 2. Process, and 3. Standard. 'Planning' is the most important stage in the development of completion criteria. It is the stage when an appropriate end land use is determined, analogue sites are assessed, a rehabilitation plan developed along with specified design standards ensuring implementation of best practice techniques, and a process of risk assessment implemented. The 'Operational Monitoring Stage' focuses on rehabilitation success during the period of ecosystem development. This stage is concerned largely with rehabilitation monitoring, from which performance standards can be developed to gauge rehabilitation success for specific periods during revegetation development. The initial task in Stage 2 is to ensure all aspects of the rehabilitation plan have been implemented as specified in Stage 1, and meet agreed design standards. The final stage of the completion criteria process, 'Post Mining Hand Over', is to ensure the rehabilitated site is safe, and able to successfully revert to the end land use.
While plant biodiversity parameters formed the focus of the current study, a variety of other functional ecosystem components may also make sound assessment criteria for determining rehabilitation success. Increasing the knowledge base for other functional components in arid and semi-arid ecosystems would further increase the ability to accurately determine rehabilitation success.
APA, Harvard, Vancouver, ISO, and other styles
23

Huang, Hai-yen. "The role of coping style and need for closure in relapse." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B29726888.

Full text
APA, Harvard, Vancouver, ISO, and other styles
24

Hartzer, Suzette. "The liability of historical mine authorization holders for rehabilitation / Suzette Hartzer." Thesis, North-West University, 2009. http://hdl.handle.net/10394/8386.

Full text
Abstract:
Historically, irresponsible mining companies have escaped their duty to rehabilitate. The Mineral Petroleum Resources Development Act does not oblige mining companies to rehabilitate if their operations ceased before the Minerals Act came into force. In the court case De Beers Consolidated Mines v Ataqua Mining (Pty) Ltd and others 2006 1 SA 432 (T), the court held that the Mineral Petroleum Resources Development Act is not applicable to tailings dumps that were created through mining that had been conducted under the Minerals Act. This ruling leaves unanswered the question about who would be liable to rehabilitate old order tailings dumps once such tailings dumps are re-mined or not mined at all. The aim of this dissertation is to determine whether companies that ceased mining operations before the Mineral Petroleum Resources Development Act came into effect could be held liable for rehabilitation by introducing the scenario that applied in the De Beers court case.
Thesis (LL.M. (Environmental Law))--North-West University, Potchefstroom Campus, 2010
APA, Harvard, Vancouver, ISO, and other styles
25

Altamirano-Soto, Pablo, Jorge Supa-Urrutia, Humbero Pehovaz-Alvarez, Carlos Raymundo, Nestor Mamani-Macedo, and Francisco Dominguez. "Filling Method Implementing Hydraulic Lime for Reusing Mine Tailings and Improve Sustainability in Conventional Peruvian Underground Mines." Springer, 2020. http://hdl.handle.net/10757/656169.

Full text
Abstract:
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.
Mining in Peru has existed for several decades, and for several years, there has been no proper environmental management of the impact of this activity on the environment and society in general, whether it be gas emissions, the presence of acidic water, or the generation of mining tailings. One of the most prominent examples involve mine tailings; these are by-products of mining processing plants and are stored in a dam known as a tailings dam. Like any extraction activity, mining generates large amounts of waste material that could become potential risks to the environment and society. Using hydraulic fills, the mine tailings contained in tailings dams could be reused. These fills seek to decrease the volume of stored tailings to prevent any future dam collapses, as observed in Brazil with the Vale mining company, where its tailings dam collapsed and caused more than 200 deaths.
APA, Harvard, Vancouver, ISO, and other styles
26

Camelo, Marta Sawaya Miranda. "Fechamento de mina : análise de casos selecionados sob os focos ambiental, econômico e social." Programa de Pós-Graduação em Engenharia Geotécnica. Núcleo de Geotecnia, Escola de Minas, Universidade Federal de Ouro Preto, 2006. http://www.repositorio.ufop.br/handle/123456789/2355.

Full text
Abstract:
Submitted by Maurílio Figueiredo (maurilioafigueiredo@yahoo.com.br) on 2013-02-22T20:37:44Z No. of bitstreams: 1 DISSERTAÇÃO_FechamentoMinaAnálise.pdf: 10307728 bytes, checksum: 1e0a8b681953d6247fca43770c70a6dc (MD5)
Approved for entry into archive by Neide Nativa (neide@sisbin.ufop.br) on 2013-02-25T14:20:57Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO_FechamentoMinaAnálise.pdf: 10307728 bytes, checksum: 1e0a8b681953d6247fca43770c70a6dc (MD5)
Made available in DSpace on 2013-02-25T14:20:57Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO_FechamentoMinaAnálise.pdf: 10307728 bytes, checksum: 1e0a8b681953d6247fca43770c70a6dc (MD5) Previous issue date: 2006
ABSTRACT: The concern about the environment come imposing itself for a few decades, becoming today, a world phenomenon and causing a rethink of attitudes in all the activities that intervene direct or indirectly in the environment. In the mining, according to this new conscience, the society also comes demanding a new boarding for the question of mine closure (known internationally for design for mine closure). A joint effort has been materialized, causing adjustments in the mining projects since its implantation, until its deactivation and closing, as well as in the legal systems that intervene in this aspect in Brazil. There is still a lack of studies developed in this area and a lot still has to be done, therefore the choice of the subject for this thesis. It is intended, during this work: to present a description of the evolution of Brazilian legislation; to approach some aspects of the international legislation relating them with the current trends; to propose a discussion about effectiveness of the fulfillment of the legislation and its impediments in the process of mining closure. It is expected to culminate this work discussing concrete cases of mining closure that allow the improvement of future plans of mining closure.
A preocupação com a questão ambiental vem se impondo há algumas décadas, tornando-se, hoje, um fenômeno mundial e provocando um repensar de atitudes em todas as atividades que interferem direta ou indiretamente no meio ambiente. Na mineração, em decorrência dessa nova consciência, a sociedade vem exigindo uma nova abordagem também para a questão do fechamento de mina (conhecido internacionalmente por design for mine closure). Um esforço conjunto vem se materializando, provocando ajustes nos projetos de mineração desde sua implantação até sua desativação e fechamento, bem como nos ordenamentos jurídicos que interferem nesse aspecto no Brasil. Ainda são poucos os estudos desenvolvidos nessa área, e muito ainda precisa ser feito, por isso a escolha do tema para essa dissertação. Pretende-se, no desenrolar deste trabalho: apresentar um histórico da evolução da legislação brasileira vigente; abordar alguns aspectos da legislação internacional relacionando-as com as tendências atuais; propor uma discussão sobre a efetividade do cumprimento da legislação e seus entraves no processo de fechamento de mina. Espera-se culminar esse trabalho discutindo casos concretos de fechamento de mina que permitam o aprimoramento de futuros planos de fechamento de mina. __________________________________________________________________________________________________________________________________________________
APA, Harvard, Vancouver, ISO, and other styles
27

Barrezueta-Delgado, Erika, Naysha Blas-Trujillo, Yaneth Vasquez-Olivera, Carlos Raymundo, Nestor Mamani-Macedo, and Javier M. Moguerza. "A Cyanide Tailings Management Method Using Pseudomonas Fluorescens to Improve Conventional Treatments for Progressive Closure at Small Gold Mines." Springer, 2020. http://hdl.handle.net/10757/656170.

Full text
Abstract:
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.
Based on the review of different research studies, we could assess that, due to their unique biological features, microbes, specifically bacteria, could be used to repair damaged soils with heavy metal and toxic compound contents. Furthermore, these microorganisms are metabolically capable to oxidize cyanide and its by-products to generate less-toxic compounds at the end of the process. This research proposal seeks to improve conventional mine closure designs, thus counteracting their negative short-term, medium-term, and long-term after-effects to the environment. The proposed technique as a solution, therefore, is microbial remediation, using pseudomonas fluorescens bacteria to oxidize this compound to non-toxic components. It will ensure operational continuity for the deposits and, in turn, the sustainability of the entire mining industry.
APA, Harvard, Vancouver, ISO, and other styles
28

Pauw, Marco Johann. "Monitoring ecological rehabilitation on a coastal mineral sands mine in Namaqualand, South Africa." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17886.

Full text
Abstract:
Thesis (MSc)--Stellenbosch University, 2011.
ENGLISH ABSTRACT: The Exxaro Namakwa Sands heavy mineral sands mine at Brand-se-Baai, on the west coast of South Africa, is an important source of income, development and job-creation in the region. However, this comes at a great environmental cost, as strip mining causes large scale destruction of ecosystems through the complete removal of vegetation and topsoil. This is particularly problematic in an environment, such as Namaqualand, where the arid and windy climate, as well as saline and nutrient-poor soils, hamper rehabilitation. These environmental constraints create the need to develop a site-specific rehabilitation program. At Namakwa Sands the objective of rehabilitation is to “rehabilitate and re-vegetate disturbed areas and establish a self-sustaining Strandveld vegetation cover in order to control dust generation, control wind and water erosion, as well as restore land capability. In general, vegetation will be rehabilitated to a minimum grazing standard capable of supporting small stock (sheep) grazing.” In order to achieve this Namakwa Sands conducted rehabilitation experiments with topsoil replacement, seeding of indigenous species and translocation of mature plants. Monitoring is an important part of the rehabilitation process as it allows rehabilitation practitioners to evaluate success and to adapt their management strategies and rehabilitation methods, as well as to evaluate and, if necessary, change their rehabilitation objectives. This study forms part of the monitoring process at Namakwa Sands. It assesses the success of sites that were experimentally rehabilitated in 2001 and a site that was rehabilitated in 2008, using current practice, in order to identify possible management requirements on rehabilitated sites as well as improvements on rehabilitation objectives, methods and monitoring. This study also tests the Landscape Function Analysis (LFA) as rehabilitation monitoring tool by correlating LFA indices with traditional measurements of biophysical variables or their surrogates. Results showed that experimental sites were not successful in returning vegetation cover and plant species richness to the required levels, but did achieve the grazing capacity objective. These sites will need adaptive management to achieve the vegetation cover and plant species richness objectives. The recently rehabilitated site achieved the three-year vegetation cover and plant species richness objectives, as well as the grazing capacity objective, within two years after rehabilitation. Namakwa Sands should therefore continue using the current rehabilitation method. However, rehabilitation should be done in multiple stages in future to decrease the mortality of nursery cuttings and to facilitate the return of late successional species to rehabilitated sites. The sustainability of small stock farming on rangeland with the grazing capacity that is identified as the minimum objective is questionable and this merits further investigation. LFA can be a useful tool to monitor nutrient cycling and soil stability at Namakwa Sands, provided that enough replicates are used. However, LFA cannot be used as is to assess water infiltration at Namakwa Sands, due to assumptions in the calculation of this index that do not hold for the Namaqualand environment. Landscape functioning should be monitored annually to complement vegetation surveys.
AFRIKAANSE OPSOMMING: Die Exxaro Namakwa Sands swaarminerale-sandmyn by Brand-se-Baai, aan die weskus van Suid-Afrika, is ‘n belangrike bron van inkomste, ontwikkeling en werkskepping in die streek. Daar is egter negatiewe omgewingsimpakte aan verbonde, aangesien die strookmyntegniek grootskaalse vernietiging van ekosisteme veroorsaak deur die algehele verwydering van die plantegroei en bogrond. Dit is veral problematies in ‘n omgewing, soos Namakwaland, waar die droë en winderige klimaat, asook die souterige en voedingstof-arme grond, rehabilitasie belemmer. Hierdie beperkings wat deur die omgewing veroorsaak word skep die behoefte om ‘n rehabilitasieprogram te ontwikkel wat spesifiek is tot die terrein. Die doel van rehabilitasie by Namakwa Sands is om te rehabiliteer en herplant op versteurde gebiede en om selfonderhoudende Strandveld plantbedekking te vestig om sodoende stofgenerering te beheer, om wind- en watererosie te beheer, en om grondgebruik-vermoë te herstel. In die algemeen sal plantbedekking gerehabiliteer word tot ‘n minimum weidingskapasiteit wat kleinveeweiding (skaapweiding) kan onderhou. Om dit te bereik het Namakwa Sands rehabilitasie-eksperimente uitgevoer met terugplasing van bogrond, saai van inheemse spesies en oorplanting van volwasse inheemse plante. Monitering is ‘n belangrike deel van die rehabilitasieproses, aangesien dit rehabilitasie-praktisyns in staat stel om sukses te evalueer en om bestuurstrategieë en rehabilitasiemetodes aan te pas, sowel as om rehabilitasiedoelwitte te evalueer en, indien nodig, aan te pas. Hierdie studie vorm deel van die moniteringsproses by Namakwa Sands. Dit assesseer die sukses op persele wat eksperimenteel gerehabiliteer is in 2001 en ‘n perseel wat in 2008 gerehabiliteer is, volgens die huidige praktyk, om moontlike bestuursbehoeftes op gerehabiliteerde persele en verbeteringe aan rehabilitasiedoelwitte, -metodes en –monitering te identifiseer. Hierdie studie toets ook die geskiktheid van die Landscape Function Analysis (LFA) as ‘n rehabilitasie-moniteringsinstrument deur LFA-indekse met tradisionele metings van biofisiese veranderlikes of hul surrogate te korreleer. Resultate dui daarop dat eksperimentele persele nie suksesvol was om plantbedekking en plantspesies-rykdom tot die vereiste vlakke te herstel nie, maar wel die weidingskapasiteit-doelwit bereik het. Hierdie persele benodig aanpassingsbestuur om plantbedekking- en plantspesiesrykdom-doelwitte te bereik. Die perseel wat onlangs gerehabiliteer is, het binne twee jaar na rehabilitasie die drie-jaar plantbedekking- en plantspesiesrykdom-doelwitte, sowel as die weidingskapasiteitdoelwit bereik. Daarom moet Namakwa Sands voortgaan om die huidige rehabilitasiemetode te gebruik. Rehabilitasie moet egter in die toekoms in veelvoudige stadiums gedoen word om die mortaliteit van kwekery-steggies te verminder en om die terugkeer van laatsuksessionele spesies na gerehabiliteerde persele te fasiliteer. Die volhoubaarheid van kleinveeboerdery op weiveld met die minimum vereiste weidingskapasiteit word betwyfel en vereis verdere ondersoek. LFA kan ‘n bruikbare instrument wees om siklering van voedingstowwe en grondstabiliteit te monitor by Namakwa Sands indien genoeg repliserings gebruik word. LFA kan egter nie in die huidige vorm gebruik word om waterinfiltrasie by Namakwa Sands te assesseer nie, aangesien daar aannames in die berekening van die indeks is wat nie juis is in die Namakwaland omgewing nie. Landskapfunksionering behoort jaarliks gemoniteer te word om plantopnames aan te vul.
APA, Harvard, Vancouver, ISO, and other styles
29

Bell, Maria Aletta. "Monitoring rehabilitation success using remotely sensed vegetation indices at Navachab Gold Mine, Namibia." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97888.

Full text
Abstract:
Thesis (MA)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Remote sensing and vegetation indices were evaluated for its usefulness to monitor the success of the rehabilitation programme of the decommissioned tailings storage facility (TSF1) of the Navachab Gold Mine, Karibib, Namibia. The study aimed to objectively illustrate the rehabilitation progression from tailings (baseline) to soil (capping) and vegetation (planted as well as natural). Baseline data sets of 2004 and 2005 were compared with imagery of 2009, 2010 and 2011. All the images were subjected to panchromatic sharpening using the subtractive resolution merge (SRM) method before georegistration. As no recent accurate topographical maps were available of the study area, the May 2010 image was used as a reference image. All other images were georegistered to this image. A number of vegetation indices (VIs) were evaluated. The results showed that the normalised difference vegetation index (NDVI) and the transformed vegetation index (TVI) provided the most promising results. Although the difference vegetation index (DVI) and enhanced vegetation index (EVI) distinguished the vegetation, rock, and soil classes, it was not as successful as the other VIs in classifying the rain water pond. TVI and NDVI were further evaluated for their efficacy in detecting changes. This was done by generating a series of change images and by qualitatively comparing them to false colour images of the same period. Both the NDVI and TVI delivered good results, but it was found that the TVI is more successful when water is present in the images. The research concludes that change analyses based on the TVI is an effective method for monitoring mine rehabilitation programmes.
AFRIKAANSE OPSOMMING: Afstandswaarneming en plantegroei-indekse is ge-evalueer vir die gebruikswaarde daarvan om sukses van die rehabilitasieprogram vir die geslote slykdam of tailings storage facility (TSF1) van die Navachab Goudmyn, Karibib, Namibië vas te stel. Die studie se doelwit was om die progressie in die rehabilitasie van slyk (basislyn) na grond (dekmateriaal) en plantegroei (aangeplant en natuurlik) te illustreer. Basislyndatastelle 2004 en 2005 is vergelyk met 2009, 2010, en 2011 beelde. Al die beelde is panchromaties verskerp deur die subtractive resolution merge (RSM) metode voor georegistrasie uit te voer. Aangesien geen onlangse, akkurate topografiese kaarte van die studiegebied beskikbaar was nie, is die beeld vir Mei 2010 as ‘n verwysingsbeeld gebruik. Al die ander beelde is op die laasgenoemde beeld gegeoregistreer. Die resultate het gewys dat die normalised difference vegetation index (NDVI) en die transformed vegetation index (TVI) die mees belowende resultate lewer. Al het die difference vegetation index (DVI) en enhanced vegetation index (EVI) goed onderskei tussen plantegroeiklasse en grond- en gesteentesklasse was dit nie so suksesvol met die klassifikasie van die reënwaterpoel nie. TVI en NDVI is verder geëvalueer vir effektiwiteit om verandering waar te neem. Dit is gedoen deur ‘n reeks van veranderingsbeelde te skep en dit dan kwalitatief met die valskleur-beelde vir dieselfde tydperk te vergelyk. Beide die NDVI en TVI het goeie resultate gelewer, maar die TVI was meer suksesvol om beelde met water te klassifiseer. Die navorsing lei tot die gevolgtrekking dat veranderingsanalises met die TVI ‘n effektiewe metode vir die monitoring van rehabilitasie programme is.
APA, Harvard, Vancouver, ISO, and other styles
30

Sullivan, Nora M. "Comparing Acid and Metal Loading Before and After Stream Capturing Subsidence Closure." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1450952105.

Full text
APA, Harvard, Vancouver, ISO, and other styles
31

Paugh, Charles R. "Vocational Rehabilitation for Persons with Dual Diagnoses: Specific Service Patterns that Enhance Earnings at the Time of Case Closure." Connect to this title online, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1046216863.

Full text
Abstract:
Thesis (Ph. D)--Ohio State University, 2003.
Title from first page of PDF file. Document formatted into pages; contains xiii, 170 p.: ill. (some col.). Includes abstract and vita. Advisors: Bruce Growick and John Finch, College of Education. Includes bibliographical references (p. 160-170).
APA, Harvard, Vancouver, ISO, and other styles
32

Breyl, Jacobus. "Sinkhole formation due to subsurface erosion above undermined ground." Diss., University of Pretoria, 2019. http://hdl.handle.net/2263/73464.

Full text
Abstract:
In November 2016, 38 sinkholes formed due to subsurface erosion above undermined ground on Donkerhoek farm near Sasolburg. The fact that the sinkholes formed more than 24 years after mining in the area ceased, emphasised the need for a method to predict the likelihood of sinkhole formation due to subsurface erosion. This is especially relevant for mining houses required to quantify their mine closure risks. The purpose of this study was to investigate the mechanisms and soil properties involved in the formation of the 38 sinkholes on Donkerhoek farm through a fieldwork and laboratory testing programme and develop a method to predict the likelihood of sinkhole formation. Three areas were selected for test pit excavation: an area with large sinkholes, one with small sinkholes and a third with no sinkholes but with a history of subsidence crack formation. The same mechanism of sinkhole formation was observed in both the large and small sinkhole areas: at the soil-rock interface, soil was being eroded into a subsidence crack in the rock, resulting in an upwards migrating cavity and the eventual formation of a sinkhole on surface when the cover over the cavity collapsed. This was the first time that this mechanism was observed in the Sasolburg area, having previously only been identified in the Secunda area. The laboratory tests, carried out on samples obtained during the fieldwork, included foundation indicator, dispersivity, XRF and XRD, soil water retention curves, consolidated undrained triaxial and permeability tests. By comparison of the results from the different study areas, it was concluded that the larger sinkholes form in areas with highly dispersive soils, higher clay content, higher swell potential and a higher capacity to retain suctions when wetted. The following soil properties and factors were identified as the main contributors to sinkhole formation: • The strength of the lid, which is highly influenced by the unsaturated behaviour of the lid material. The lid strength determines the sinkhole diameter; • The erodibility of the material which is influenced by dispersivity and the material obtaining a crumb structure due to desiccation; • The activity of the soil, which influences the volume changes during drying and thereby the width and depth of desiccation cracks; and • The thickness of the soil layer overlying the rockhead. With the critical factors identified, the Van der Merwe method to predict sinkhole size was used as basis to develop an index method to predict the likelihood of sinkhole formation due to subsurface erosion above undermined ground. The method considers combinations of the following factor groups to express a high or low likelihood of the formation of large or small sinkholes in a particular area: • The strength of the lid material, mainly influenced by the unsaturated behaviour of the soil; • The capacity for cavity formation (CCF), which combines the dispersivity, erodibility and activity of the soil; and • The influence of the thickness of the soil layer overlying the rock, evaluated by calculating the ratio between crack width in the rock and the soil layer thickness.
Dissertation (MEng)--University of Pretoria, 2019.
Civil Engineering
MEng (Geotechnical Engineering)
Unrestricted
APA, Harvard, Vancouver, ISO, and other styles
33

Neri, Ana Claudia. "Tratamento de incertezas no planejamento do fechamento de mina." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-14052014-153850/.

Full text
Abstract:
Incertezas são inerentes ao planejamento de fechamento de mina, atividade que requer o trato de complexas questões técnicas, sociais, econômicas e ambientais em perspectiva de longo prazo e com base em informação e conhecimentos fragmentados e não sistemáticos. Incertezas nas tomadas de decisões podem resultar em ações de fechamento ineficazes e/ou ineficientes, ou seja, que não alcancem os objetivos esperados e/ou demandem vultosos recursos financeiros, humanos e outros. Esta pesquisa procurou compreender a natureza das incertezas presentes no processo de planejamento de fechamento de mina por meio da definição de suas causas, tipos e formas de tratamento e analisar como são abordadas em guias de boas práticas. Incerteza, no contexto do planejamento de fechamento de mina, é entendida como uma situação na qual há conhecimento incompleto, imprevisibilidade ou não há um único entendimento do processo a ser gerenciado. Nesse contexto, as principais causas das incertezas são, respectivamente, insuficiência de conhecimento, variabilidade do comportamento dos componentes do processo, no tempo e no espaço e diferentes enfoques ou recortes da situação analisada. Foram definidos oito tipos de incertezas pertinentes ao planejamento de fechamento de mina, agrupadas em três componentes (i) naturais (incertezas ambientais, geológicas, geotécnicas), (ii) técnicos (incertezas operacionais, tecnológicos), (iii) socioeconômicos (incertezas sociais, regulatórias, gerenciais, econômicas). Associações de empresas e órgãos públicos têm publicado guias e documentos de diretrizes para orientar as empresas a planejar o fechamento de mina. No entanto, esses guias não parecem ser explícitos quanto ao reconhecimento e tratamento de incertezas no planejamento de fechamento. Assim, por meio da técnica de análise de conteúdo, quatro guias de boas práticas foram examinados para verificar, se e como, abordam ou recomendam diretrizes para lidar com incertezas no planejamento de fechamento. Os resultados mostraram que certos tipos de incerteza são reconhecidos pelos guias, que recomendam algumas diretrizes para lidar, em especial, com incertezas ambientais, sociais, regulatórias e econômicas. Porém, (i) os guias não demonstram uma clara concepção ou entendimento das incertezas inerentes ao planejamento de fechamento de mina, embora em algumas situações reconheçam sua existência e influência; (ii) a maior ênfase dos guias em relação aos aspectos ambientais pode induzir as empresas a alocarem responsabilidades para tratar questões relativas ao fechamento ao departamento de meio ambiente ou de relações comunitárias e não induzirem que sejam tratadas a nível estratégico pela alta direção da empresa e (iii) a maioria dos guias, não fornece diretrizes para melhorar e avaliar a qualidade das informações/conhecimento nas tomadas de decisões. É proposto um esquema analítico para lidar com as incertezas no planejamento de fechamento, composto por três etapas: (i) identificação dos tipos de incertezas; (ii) definição das causas das incertezas e (iii) definição de ações e estratégias para lidar com as incertezas. Espera-se que a proposta possa contribuir para que as empresas de mineração considerem, de maneira estruturada, as incertezas em suas decisões relativas ao fechamento, e que órgãos públicos possam utilizá-la para avaliar as informações apresentadas em planos de fechamento e demais estudos técnicos relativos à autorização e licenciamento de projetos.
Uncertainties are intrinsic to the mine closure planning, activity which involves complex long-term technical, social, economic and environmental questions, based on fragmented and non-systematic information and knowledge. Uncertainties in decision-making may lead to inefficacious closing actions, which do not achieve the expected goals and/or demand a lot of financial, human and other types of resources. This research aimed at understanding the nature of the uncertainties involved in the mine closure planning process by defining their causes, types and ways to deal with them and analyzing how they are treated in best-practice guidelines. Uncertainty in the context of mine closure planning is understood as a situation in which there is incomplete knowledge, unpredictability or no single way to understand the process to be managed. In this context, the main causes of uncertainties are respectively: lack of knowledge, time and space variability of the behavior of the components in the process and different approaches or understanding about the analyzed situation. Eight types of uncertainties regarding the mine closure planning have been defined and grouped in three components: (i) natural (environmental, geological and geotechnical uncertatinty), technical (operational and technological uncertatinty), (iii) social- economical (social, regulatory, management and economic uncertainties). Enterprises associations and public agencies have been publishing guidelines to provide the companies with advice on how to plan the mine closure. However, these guidelines do not seem to be explicit in recognizing and dealing with uncertainty in the closure planning. Thus, using the content analysis technique, four best practice guidelines have been examined in order to determine whether and how they approach or produce advice to deal with uncertainty in the closure planning. The results have shown that certain types of uncertainty are addressed by the guidelines, which provide some advices to deal particularly with environmental, social, regulatory and economic uncertainties. Nevertheless, the guidelines: (i) do not present a clear concept or understanding about the uncertainty which are intrinsic to the mine closure planning, although in some situations the recognize their existence and influence; (ii) the higher emphasis on the environmental aspects used by the guidelines may induce the companies to allocate reponsibilities to deal with x questions related with the closure, the environmental department or the relations with the community and cause them not be treated in strategic level by the company and (iii) most guidelines do not provide advices on how to improve and evaluate the quality of the information/knowledge of the decision-making. An analytical scheme composed by three steps is proposed to deal with the uncertainties in the closure planning: (i) identification of the uncertainty type; (ii) definition of uncertainty causes and (iii) definitions of actions and strategies to deal with uncertainties. This proposal may contribute for the mining companies to consider in a structured way the uncertainties in their closure-related decisions and for the public agencies to evaluate the information present in closure plans and other technical studies related to licensing projects.
APA, Harvard, Vancouver, ISO, and other styles
34

Singh, Srikesh. "A comparative analysis of financial guarantee instruments for mine closure in relation to the interests of medium-sized mines." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/60095.

Full text
Abstract:
In this dissertation I comparatively analyse the various financial guarantee instruments for mine closure in relation to the interests of medium sized mines. I do this not to compare each instrument against each another but rather in order to ascertain which instruments are more beneficial to medium sized mine companies when included in a state legislation or a contract. Mine closure is clearly a certainty for all mines, however acquiring sufficient funding in order for holistic closure to occur has always been problematic. Thus the use of financial guarantee instrument may mitigate such concern and streamlining the choice will lead to attaining the holistic mine closure objectives. In chapter 1 I trace the history of mine closure as concept which has developed since the 1870s and I illustrate how the concept of mine closure has taken into consideration technical, social and environmental aspects. I do so in order to reinforce not only the scope of mine closure but to further emphasise the progression of the concept. Finally, I establish the current concept of mine closure, representing a meticulous concept comprising of far more than the traditional physical closure. Arising from this meticulous notion I discuss in chapter 2 the need for funding mine closure as the foremost concern regarding mine closure. I highlight the key justifications for the necessity for funding, I discuss the likely sources of such funding and I argue with whom the responsibility of funding falls onto. As the substantive core of this paper, in chapters 3 and 4 I introduce the most commonly opted for financial guarantee instruments and the most significant interests of medium sized mines regarding the financing of mine closure respectively. I deliberate concisely on each of the following instruments, namely: letter of credit; surety bond; cash trust fund; insurance scheme and self-guarantee and I discuss very briefly the most significant interests, namely: profitability, liquidity, accessibility, corruption and tax implications. Finally in chapter 5 I analyse and compare the discussed financial guarantee instruments for mine closure against the interests of medium sized mines in order to establish which are the most beneficial to the medium sized mine company in the completion of holistic mine closure.
Mini Dissertation (LLM)--University of Pretoria, 2017.
Public Law
LLM
Unrestricted
APA, Harvard, Vancouver, ISO, and other styles
35

Brandenburg, Cristi L. B. A. "Cognitive Ability and Vocational Interest Predictors of Case Closure for Individuals with Psychiatric Disabilities." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1346171198.

Full text
APA, Harvard, Vancouver, ISO, and other styles
36

Treloar, Kate. "Nature and extent of contamination at the abandoned Wheal Ellen mine and implications for rehabilitation /." Title page, table of contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09SB/09sbt788.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
37

Mikli, Markus H. "Revegetation of coal mine dumps to ameliorate effects of acidic seepage." Curtin University of Technology, Department of Environmental Biology, 2001. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=12531.

Full text
Abstract:
Species prescriptions are developed for revegetating abandoned acidic coal overburden seepage sites in the Collie region of Western Australia. The research involved selecting appropriate plant species and determining successful methods of enhancing revegetation. Candidate species were screened for tolerance to acidic overburden materials, local climate conditions and metal toxicity. Methods tested included improving spoil conditions and trialing an alternative method for seeding.Twelve species of native plants were tested for tolerance in two acid overburden materials in pot and field trials. Eucalyptus robusta is the most tolerant, Eucalyptus camaldulensis and Eucalyptus cladocalyx are highly tolerant, Eucalyptus rudis and Melaleuca hamulosa demonstrate potential, provided adequate soil moisture is available.An important growth restriction factor in acid soils is the presence of free aluminium ions. A glasshouse trial performed on seven species for tolerance to aluminium toxicity revealed E. robusta as most tolerant and E. camaldulensis and Kunzea ericifolia a highly tolerant. E. rudis and M. hamulosa are moderately tolerant, but E. cladocalyx and Eucalyptus diversicolor are very sensitive to aluminium.Various methods were trialed to increase growth of seedlings transplanted on to acidic overburden sites. Both commercial cow manure and slow-release fertiliser tablets increase growth, whereas commercial potting mix and lime do not. Inoculation of plants with the ectomycorrhiza fungus Pisolithus tinctorius increases the amount of infection in roots but does not enhance plant growth.Supplementary fertilisation is necessary to maintain growth (nitrogen) and restore chlorophyll production (phosphorus) in fast growing eucalypt seedlings planted into typical acidic spoils. Poor levels of nutrient availability in such acidic sites appear to be the primary factor in ++
retarding growth. In the absence of supplementation, foliage reddening is observed in several species.An alternative method of seeding dumps is fascining. Prepared dump surfaces may be covered with capsule-laden branchwood of myrtaceous species. Material of the locally available Kunzea ericifolia is effective in producing many seedlings. Subsequent seedling growth is enhanced with fertiliser and lime addition.
APA, Harvard, Vancouver, ISO, and other styles
38

Tshivhandekano, Aubrey Ndinannyi. "Documenting reclamation and closure of Ermelo coal mines : implications for developing a national strategy for mine reclamation in South Africa." Diss., Pretoria : [s.n.], 2004. http://upetd.up.ac.za/thesis/available/etd-12082005-152604.

Full text
APA, Harvard, Vancouver, ISO, and other styles
39

[Verfasser], Toni, Carsten [Akademischer Betreuer] Drebenstedt, Carsten [Gutachter] Drebenstedt, and Peter [Gutachter] Moser. "Economic model of mine closure and its potential for economic transformation / Toni ; Gutachter: Carsten Drebenstedt, Peter Moser ; Betreuer: Carsten Drebenstedt." Freiberg : Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2015. http://d-nb.info/1220912042/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles
40

Buthelezi, Mbekezeli Simphiwe. "A critical evaluation of local level responses to mine closure in the Northwestern KwaZulu-Natal coal belt region, South Africa." Thesis, Rhodes University, 2004. http://hdl.handle.net/10962/d1005497.

Full text
Abstract:
The de-industrialisation process that was a common feature of North America and Western Europe in the 1970s, through into the 1980s has become an observable feature in African countries and South Africa in particular in the last two decades. Globally, hard hit areas include those associated with the early Industrial Revolution characterised by mass production and the agglomeration of iron and steel, coal and textile industries. General changes in the global market, especially the falling demand for extractive heavy minerals like coal and gold have also affected many countries region and localities. In the case of South Mrica, the previous high economic dependence on mined minerals like coal and gold has resulted in many once prosperous mining regions of the country being reduced to a shadow of their former selves. The worst affected areas in South Africa are those of the Klerksdorp Goldfields in the North West Province and Free State Goldfields, with the latter alone losing 100,000 jobs during the 1990s. This trend has also been acute in the coal-mining industry of the KwaZulu-Natal province since the late 1970s. The firms that had grown in the shadow of the major mining company supplyipg machinery, or who processed the semi-manufactured product are also severely affected by the closing down and restructuring in the mining and iron industries. These industries have often been forced to close down because of a break in the vital connections they developed with these mining industries. Such localised economic crisis has encouraged the universal trend towards the devolution of developmental responsibilities to the local governments and other local stakeholders to - empower them to respond to these changes. This study investigated the local economic initiatives which have been undertaken in the three municipalities of north-western KwaZulu Natal i.e. Utrecht, Dundee and Dannhauser to respond to the closures which have taken place in the mining industry of this region, which used to be among the most prosperous coal mining regions of South Africa. Using their new developmental mandate the local governments, in partnership with the communities and other external interveners have tried to respond to these localised economic crisis and also indirectly to the general poverty and underdevelopment, which characterises this region of KwaZulu-Natal. The effects of apartheid policies, and previous discriminatory rural development policies in, particular, and the Regional Industrial Development policy, which was intensively applied in the 1980s by the pre-1994 government regime, have further compounded the magnitude of the challenge. The lack of capacity in some municipalities has constrained successful implementation of Local Economic Development has led to some communities acting alone to face their situation with or without external intervention.
APA, Harvard, Vancouver, ISO, and other styles
41

Cosgrove, Betty Alveen, and b. cosgrove@cqu edu au. "Mount Morgan: images and realitiesdynamics and decline of a mining town." Central Queensland University. School of Humanities, 2001. http://library-resources.cqu.edu.au./thesis/adt-QCQU/public/adt-QCQU20050427.131849.

Full text
Abstract:
Most histories and reports of Mount Morgan concentrate on the mining experience and financial achievements of the first Company rather than the mining town. This dissertation presents a social history of Mount Morgan that addresses the establishment, rise and fall of the town during the period of the first syndicate and succeeding company, 1883-1927. The thesis contends that the transformation of the landscape was to industrial, urban space where the working-class attitudes of miners and others defined a town character, despite the aspiration of many to social status through private enterprise and public influence. Further, the scope of research encompassed local involvement in colonial and state politics, and the presence of local government authority, law courts and press that placed an urban stamp on the town. Issues discussed also relate to geographic, climatic and single company influences that caused the difference between Mount Morgan and other mining towns that did not survive. The traditional perception of mining town impermanence was contradicted at Mount Morgan, where town and suburban communities were witness to a range of collective support in religious adherence, benefit associations, fraternalism and ritual, leisure, sport, education, and social cohesion in times of mining disaster. Moreover, despite increasing familial connections, antagonistic attitudes prevailed between the defensively parochial town of Mount Morgan and the nearby regional centre of Rockhampton. The rise of unionism at Mount Morgan challenged an apathetic working-class population to workplace solidarity in reaction to the Company's long established, almost feudal control of the town as well as the mine. It is argued that, despite a decade of failing ore markets and soaring production costs at the mine, the attitudes and actions of a union dominated workforce were paramount in decline of the town and ultimate closure of the mine. Mount Morgan survived the exodus of thousands of residents. A defiant place, the town exhibited a pride bolstered by the perpetuation of myths that presented a public image shielded from the life-long realities of economic and social adversity.
APA, Harvard, Vancouver, ISO, and other styles
42

Hattingh, Raina. "Framework to guide mine-related land use planning towards optimisation of the coal mining rehabilitated landscape." Diss., University of Pretoria, 2018. http://hdl.handle.net/2263/65312.

Full text
Abstract:
The post-mining land use optimisation framework developed as part of this research underpins the need for examining site-specific decisions within the regional land planning context as well as in relation to the social, economic, and political perspectives within the mine’s localised planning domain. It emphasizes that the spatial and temporal planning and implementation of rehabilitation and land use-related activities remain continually changing throughout the mining life cycle. This implies that amendments, refinements or corrective action should be an integral aspect of this planning, improving the trajectory towards success as new site knowledge and learnings becomes available. Rehabilitation activities should be implemented as soon as site disturbance (construction) starts and maintained throughout the operational and decommissioning periods. More importantly, these activities remain even more pertinent to the monitoring and maintenance period, during which successful implementation of the pre-defined land use/s can be demonstrated. Rehabilitation-, land use and mine closure plans are hence ‘living’, changing tools, aligned towards a common goal – defining a resilient post-mining landscape that will, ultimately, enable harnessing the altered landscapes’ new characteristics to optimise services to post-mining communities that either provides similar resourcing needs from the land, or alternative resources that contribute to the long-term viability of the area.
Dissertation (MSc) - University of Pretoria, 2018.
Coaltech Research Institute, Chamber of Mines
Chamber of Mines
Geography, Geoinformatics and Meteorology
MSc
Unrestricted
APA, Harvard, Vancouver, ISO, and other styles
43

Alghamdi, Abdulaziz Ghazi. "Rehabilitation of waste materials near lead and zinc mining sites in Galena, Kansas." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/34467.

Full text
Abstract:
Doctor of Philosophy
Department of Agronomy
DeAnn R. Presley
The abandoned lead (Pb) and zinc (Zn) mines in the Tri-State Mining District of Kansas, Missouri, and Oklahoma have left a legacy of environmental contamination. The waste materials are highly polluted, not only with Pb and Zn, but also cadmium (Cd), which often co-occurs geologically with Zn. The District includes Galena, Kansas, where mines operated between 1876 and 1970. Because limited information exists concerning these mines, three studies were done to characterize them and to investigate a way to remediate the mine waste materials. In the first study, the physical characteristics of the mine waste materials were determined. Plots at Galena that had been established by researchers in May 2006 were sampled in November 2014, 8.5 years after they had received amendments (combinations of compost, lime, and bentonite). Water content, bulk density, infiltration rate, unsaturated hydraulic conductivity, aggregate stability, and particle size distribution were determined. The physical characteristics were highly variable, and the amendments added 8.5 years earlier had no effect on them, except the wind erodible fraction (fraction <0.84 mm in diameter) which was low on treatments that contained bentonite. Because biosolids had never been applied to the mine waste materials at Galena for remediation, an experiment was done to see their effect on plant growth and availability of heavy metals. In 2014 the plots established in 2006 were sampled and a greenhouse study was set up with sudex [Sorghum bicolor (L.) Moench x S. Sudanese (P.) Staph]. Plants grew in the mine waste materials with and without biosolids, and 110-111 days after planting the roots, shoots, and heads with grain were harvested and analyzed for heavy metals. At the same time, the mine waste materials were analyzed for heavy metals, organic carbon (C), nitrogen (N), and phosphorus (P). Plants grew better with biosolids than without biosolids, and only the plants grown with biosolids produced heads . Plants grown without biosolids were stunted and showed severe heavy metal toxicity. Organic C and P were increased in the mine waste materials after the addition of biosolids. Thus, the biosolids increased organic C and P, and they apparently made the heavy metals less available for plant uptake. Many studies have shown the importance of attic dust in documenting metal pollution from a mine. Attic dust in Galena had never been studied, so in a third experiment, 14 dust samples in Galena were collected from interiors (attics and one basement) of nine different buildings using two methods: sweeping with a brush and vacuuming. Dust samples were analyzed for heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, and Zn), mineralogy using X-ray diffraction (XRD), scanning electron microscopy (SEM) in conjunction with energy dispersive spectroscopy (EDX), and particle size. Concentrations of Cu, Fe, Mn, Ni, and Zn in the dust were higher than in the mine waste materials. The results from XRD agreed with those from the SEM-EDX analysis. About 10% of each dust sample contained particulate matter (PM) with a diameter of less than 10 μm (PM₁₀), which is a health concern.
APA, Harvard, Vancouver, ISO, and other styles
44

Schmitzhaus, Wagner Cristiano. "Análise de cenários de planejamento de lavra para adequação de uso futuro de área de mineração de agregados." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/178456.

Full text
Abstract:
A produção de agregados para construção civil é o maior segmento mineral Brasileiro, em números de produção, sendo formada principalmente por pequenos e médios empreendimentos, normalmente utilizando técnicas e procedimentos obsoletos e pouco um nenhum planejamento tanto para extração quanto para o fechamento da mina. O fechamento de mina e posterior utilização da área ainda é um grande problema visto que existem muitas áreas mineradas em que o plano de fechamento de mina não foi executado, deixando assim um passivo socioambiental elevado, prejudicando a imagem da mineração. Existem diversos exemplos de sucesso em que antigas cavas foram utilizadas para a implantação de novos empreendimentos, como loteamentos, óperas e hotéis. Com o intuito de mostrar a importância do planejamento para fechamento e posterior utilização de área de mineração, bem como a análise ambiental e impactos da atividade na sociedade e meio ambiente, este trabalho tem o objetivo de desenvolver uma metodologia para auxiliar, principalmente o pequeno e médio produtor de agregados, sobre os impactos que o correto planejamento e manejo da operação têm sobre o retorno no uso futuro da área. Foram desenvolvidos diferentes cenários de usos futuros alternativos de uma área de mineração localizada no Litoral Norte do Rio Grande do Sul, que posteriormente foram comparados entre si em relação à recuperação mineral, impactos socioambientais, e retorno financeiro. Ao final do trabalho foi possível visualizar uma metodologia apropriada para a análise de impactos socioambientais e planejamento para preparação da área para o recebimento de novos empreendimentos. A partir destes métodos de análise dispõe-se de diversos cenários comparativos, podendo assim o empreendedor tomar a decisão mais correta em relação ao seu empreendimento minerário e futuros empreendimentos pós-fechamento.
Aggregate production for civil construction is the largest Brazilian mineral segment, in production numbers, consisting mainly of small and medium-sized enterprises, usually using obsolete techniques and procedures and little or no planning for both extraction and closure of the mine. The closure of mines and subsequent use of the area is still a major problem, there are many mined areas where the mine closure plan has not been implemented, thus leaving a high social and environmental liability, damaging the mining image, but there are several examples of use of deactivated mining sites for the implementation of diverse projects. In order to show the importance of planning for the closure and subsequent use of the mining area, as well as the environmental analysis of impacts of the activity on society and the environment, this work has the objective of developing a methodology to assist, especially small and medium aggregate producer, on the impacts that correct planning and management of the operation has on the future use of the area. Different scenarios of future uses of a mining area located in the Northern Coast of Rio Grande do Sul were developed, which were later compared to each other in relation to mineral recovery, socioenvironmental impacts, and financial return. At the end of the work it was possible to visualize an appropriate methodology for the analysis of socio-environmental impacts and planning to prepare the area to receive new projects. From these methods of analysis we have several comparative scenarios, so that the entrepreneur can make the most correct decision regarding his mining enterprise and future enterprises after the closing.
APA, Harvard, Vancouver, ISO, and other styles
45

Gillespie, Melina Jane. "Establishment success of native understorey species on coal mine rehabilitation areas in the Hunter Valley, New South Wales /." St. Lucia, Qld, 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17522.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
46

Chalwell, Shane Thomas Samuel. "Plant communities of greenstone hills of the Eastern Goldfields of Western Australia as analogues for the rehabilitation of rocky waste dumps." Chalwell, Shane Thomas Samuel (2003) Plant communities of greenstone hills of the Eastern Goldfields of Western Australia as analogues for the rehabilitation of rocky waste dumps. PhD thesis, Murdoch University, 2003. http://researchrepository.murdoch.edu.au/510/.

Full text
Abstract:
The vegetation of greenstone hills in the Kalgoorlie area of the Eastern Goldfields region of Western Australia was studied to identify the key environmental influences on community and species distribution. This information was needed to determine if plant communities of the hills could provide analogues for the rehabilitation of waste rock dumps that are produced as a consequence of open cut mining. The ridges, slopes and flats adjacent to the main slope were examined and the floristic data sorted into communities. Two structurally and floristically distinct alliances were identified, one dominated by eucalypt species and the other by Acacia quadrimarginea. The eucalypt woodland displayed a taller upper stratum and few groundlayer species and was the dominant vegetation of the flats at the base of the hills. The acacia community was a low woodland and is the dominant vegetation of the hill slopes. Both communities were dominant at an equal number of sites on the ridges of the hills. An investigation of the environmental variables found that edaphic, rather than topographic, factors were responsible for the community distribution on the hills. The eucalypt woodland showed a strong affinity to soils derived from calcrete, which had higher levels of electrical conductivity and lower exchangeable sodium percentages than the soils of the acacia low woodland. Under such conditions, the clay fraction of the soil remains in a more flocculated state allowing higher rates of water infiltration and hydraulic conductivity compared to the acacia soils. Soil nutrients were found to have a secondary influence on community distribution and had a greater effect on species distribution within alliances. A study of the seasonal variation in water content of the soils showed that more moisture is retained in the upper soil horizons in the acacia community than in the eucalypt community during the wetter part of the year, indicating the acacia soils had poorer infiltration properties than the eucalypt soils. The distribution of drought tolerant species such as A. quadrimarginea and Prostanthera incurvata was found to be correlated to soil moisture content of the dry season whilst no correlation was found for the eucalypts at any time of the year. Seasonal comparisons of leaf moisture content and xylem pressure potential showed that the eucalypts maintained their total leaf moisture content throughout the year whereas species such as A. quadrimarginea and Allocasuarina campestris recorded high levels of desiccation of their leaf tissue over the summer. The eucalypts also maintained a more consistent pre-dawn xylem pressure potential throughout the year than either A. quadrimarginea or the shrub species Dodonaea microzyga, indicating a greater degree of stomatal control and access to a more consistent soil water supply. The eucalypts require access to a greater soil volume than the acacias or shrubs in order to ensure sufficient water supplies for the maintenance of tissue moisture levels throughout the year. In this way, the eucalypts are able to effectively avoid the summer drought, whereas the acacias and shrubs are able to tolerate desiccation of their leaf tissues over this period. Investigations of the germination requirements and early seedling survival of prominent species from the greenstone hills indicated that fire may be a factor in the regeneration of most hills species. All studied species were either tolerant of or responded positively to the application of dry heat. In relation to seedling establishment on waste dumps, increasing the soil moisture content of waste dump soils increased the germination rate of most species but did not result in greater seedling survival at the end of the first summer. The provision of microsites which encouraged root development and provided protection for the young seedlings was found to be more important in reducing mortality rates in the first year than increasing the total germination. The study emphasized the importance of physical soil factors and the soil moisture regime in the distribution of eucalypt and acacia communities on the greenstone hills. A species' response to drought stress strongly influences its ability to compete for soil water on different soil types. The eucalypts studied in this project dominated on soils where there is better recharge of subsoil water reserves which can be accessed over the summer period to maintain tissue water levels. Acacias are tolerant of tissue desiccation and will compete successfully on shallower soils and where hydraulic conductivity is poor. Although the project was valuable in identifying water relations as the main control on community distribution on the hills, waste dumps are not strictly analogues of intact greenstone hills due to the differences in rock type and profile formation. Electrical conductivity levels are also higher due to extraction processes. However, the environmental relationships of the different species show that the more drought tolerant species such as Allocasuarina campestris, Acacia quadrimarginea and understorey species associated with them, may be suitable species to form the basis of vegetation reinstatement on waste dumps in the Kalgoorlie region.
APA, Harvard, Vancouver, ISO, and other styles
47

Annan, Isaac Kwamina Eshun. "Nitella congesta - a charophyte as a tool for the rehabilitation of sand mine-void wetlands at Capel, Western Australia." Curtin University of Technology, Department of Environmental and Aquatic Sciences, 2008. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=120507.

Full text
Abstract:
This research is the outcome of investigations of the ability of Nitella congesta, a charophyte, to hyperaccumulate metal contaminants, as well as contribute to the sustainable development of a chain of lakes derived from the sand mine voids at Capel 250km south of Perth, Western Australia. Studies were conducted to ascertain the taxonomy of Nitella congesta as well as its life cycle pattern in relation to the hydrological regime of the lakes of the wetlands. It was observed that a decrease in the availability of water in the lakes particularly on the onset of summer, initiated the production of fruiting bodies whiles prolonged availability of water ensured a prolonged vegetative growth.
Aquatic plants play an important role in the structuring of freshwater communities. Freshwater macrophytes such as Nitella congesta have been reported to serve as food source as well as provide refuge and shelter for macroinvertebrates. Thus the presence of freshwater macrophytes in one way or the other has a direct impact on the species abundance and diversity of macroinvertebrates that use them as their habitat. A study of the impact of Nitella congesta as a suitable macrophyte on diversity and abundance of macroinvertebrates showed a positive outcome. It was observed that species richness and diversity were high in Nitella congesta dominated sites of the lakes. Experimental outcome showed that Nitella congesta is a hyperaccumulator of metals. Both the mucilage and the thallus displayed concentrations of few metals.
The disappearance of submerged macrophytes such as charophytes in shallow lakes is a major problem caused by eutrophication. There has been an approved proposal to discharge treated waste water with a phosphorus concentration of about 4,000μg/L into the lakes of the Capel Wetlands Centre. This necessitated a study of the impact of eutrophication on the establishment of Nitella congesta as a functional macrophyte for the enhancement of the ecological structure of the wetlands.
Results showed that though eutrophication will initially increase the primary productivity of the lakes of the wetlands, the eventual consequence will be the loss of Nitella congesta as a functional macrophyte in the wetlands.
At the last stage of the study, a consistent decrease in pH readings of the lakes and lack of successful germination of Nitella congesta as a result of prolonged drought and exposure of the lake sediment was observed. This necessitated a thorough study of the impact of climate change on the establishment of Nitella congesta in the wetlands. In conclusion, it was observed that Nitella congesta could serve as a suitable tool for the rehabilitation of the wetlands.
APA, Harvard, Vancouver, ISO, and other styles
48

Rossouw, Johanna Martina. "The use of different ecosystem components as indicators of ecosystem development during platinum mine tailings rehabilitation / Johanna Martina (Juanita) Rossouw." Thesis, North-West University, 2005. http://hdl.handle.net/10394/1405.

Full text
APA, Harvard, Vancouver, ISO, and other styles
49

Morgenthal, Theunis Louis. "The assessment of topsoil degradation on rehabilitated coal discard dumps / Theunis Louis Morgenthal." Thesis, North-West University, 2003. http://hdl.handle.net/10394/112.

Full text
Abstract:
This study investigates coal discard cover soil fertility and its potential for degradation, particularly in terms of its salinisation and acidification potential. Seven rehabilitated coal discard dumps in the Witbank, Ermelo and Newcastle regions were used as study areas. All areas were rehabilitated with a cover soil layer, revegetated and annually fertilised with nitrate fertilisers, super phosphate, kraal manure and lime. Performance guideline for pH of 5.5-(6.5 i0.5)-7.5 and electrical conductivity guideline of preferably less than 200 mS.rn-' but not higher than 400 mS.m-' were set based on literature information. Soil chemical data from a three-year fertilisation programme were used to assess the fertility of the cover soil surface (0-150mm). Data collected over a three year period as well as additional electrical conductivity and pH measurements from the cover soil surface, subsoil, cover soil/coal contact zone and underlying coal itself were used to assess the occurrence of salinisation and acidification of the cover soil. The soil fertility varied significantly among dumps as well as over the three years. Results indicated an increase in ammonium acetate extractable macro elements (calcium, magnesium and potassium). With the exception of manganese, no micro-element toxicities were recorded. Iron concentrations were slightly elevated in some of the sandy cover soil layers. No increase in soluble nitrogen (nitrate and ammonium) was found and most soluble nitrogen was in the form of nitrates. In general the Bray extractable phosphate increased during the study period. It can be predicted that with the following fertiliser programme increases of exchangeable macro-elements as well as available phosphorus can be expected. The study could not indicate an increase in adsorbed or available nitrogen. Organic carbon was initially not analysed therefore no comments can be made whether organic matter increased. Four of the seven dumps surveyed had comparably similar organic carbon levels to the background samples. Overall the fertiliser programme increased the electrical conductivity and decreased the acidity of the cover soil surface. Acidity and salinity was in general not a problem at the surface of the cover soil and pH was even slightly higher in cover soil samples. The acidity and especially salinity increased at the subsoil and so did the sulphate concentrations. Calcium and magnesium sulphate were predominantly responsible for higher electrical conductivity measurements. The percentage exchangeable sodium was also predominantly less than 2% indicating that sodicity is not currently a problem in cover soil. Soil fertility was satisfactory for vegetation growth and macroelement concentrations were in the correct ratio although calcium was slightly high. An elevated sulphate concentration, in comparison to the natural grassland soils, as well as a high salinity and high acidity in the subsoil layers indicate that salinisation and acidification could deteriorate without proper management. A slightly acidic cover soil can also be attributed partially to its natural acidic pH due to the wellweathered and leach property of burrow pit. Higher than recommended salinity levels were found in subsoil samples but the occurrence of acidification of the subsoil was more dump specific. In relation to acidity and salinity guidelines only the cover soil of one dump was concerning and the larger dumps subsoil acidity and salinity were elevated. The following management strategies are proposed: a) The acidification potential, and therefore the pyrite content of the coal discard must be considered during decisions making on the rehabilitation method (clay barriers), topsoil depth, maintenance and mine closure potential. b) The occasional monitoring of the subsoil's and coal contact acidity is recommended, although not much can be done to stop acidification after cover-soil placement. c) To ensure a more sustained from of nitrogen supplementation over the long term the use of selected legumes should be investigated. Research in Europe and Australia suggested that nitrogen fixation could contribute substantially to the nitrogen for plant uptake. d) The physical properties of the topsoil (bulk density 8 soil compaction) are also being neglected and needs to be assessed occasionally and interpreted together with chemical analyses. Observations in other studies indicate that this could be the most fundamental problem for vegetation growth and not necessarily soil fertility, since soil physical properties could have a major impact on root development. Key words: Coal discard, mine rehabilitation, soil fertility, topsoil degradation, salinisation, and acidification
Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2004.
APA, Harvard, Vancouver, ISO, and other styles
50

Ware, Sonya M. "Exploring vocational rehabilitation outcomes of African Americans with emotional and behavioral disabilities a national investigation /." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1127238552.

Full text
Abstract:
Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains x, 134 p. Includes bibliographical references (p. 125-134). Available online via OhioLINK's ETD Center
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography