School of Mining Engineering (ETDs)
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Item Value creation and risk management in mining operations through an integrated reporting framework of geotechnical data, uncertainty, and materiality(University of the Witwatersrand, Johannesburg, 2025) Zermatten, Carrie; Stacey , Thomas (Dick)The research considers a stance that every aspect of the mining operation is, at its root, dependant on the geomechanical / geotechnical integrity of the excavation. A mining operation would not be able to maintain production if the excavated workings in the rock mass cannot be kept ‘open’ - even if many other aspects of the mine are very favourable (e.g. metallurgical and/or mineral processing can produce excellent recoveries, commodity prices are high etc). The research is compelled through several contributing factors, including the recognition that: • There is no national inventory of mining geotechnical data (viz. a comprehensive or extensive database) readily available to offer insight into the factual account of data provision that has supported viable mining operations to date. Such aspects would include the type, quantity, quality, and spatial distribution of data (as well as changes therein over time) associated with respective “types” of mineralised ore bodies, mining method selection, hydrogeological regime, etc. • The interpretation and application of scientific, engineering, and risk principles are often quite inconsistent within- and between- different mining operations. • The content and clarity of rock-related reporting is often highly variable - especially beyond the assessment of project viability to the actual performance over time of rock engineering, geomechanical stability, and geotechnical design dimensions of a mining excavation. • Practical realities in business (e.g. limited budget availability to particular cost centres, differing corporate priorities etc.) may limit the implementation of rock engineering decisions. The research identifies and compiles various information from a wide range of specialised topics that are commonly studied individually in smaller settings (e.g. rock mechanics, aspects prescribed under law, risk, subjective belief, governance as well as reporting transparency for mining projects [distinguished from the requirements of reporting of mineral resources and/or mineral reserves]). The topics are then related to each other, and their roles toward a holistic understanding of risk-related aspects of a mining operation are explored - with rock and geotechnical engineering as a central tenement of that consideration. The research advances the discourse of value creation and risk management in mining engineering, through: • The description of the complex interplay of components and organisations within the mining industry, as well as the potential for improving their coalescence. • The identification of opportunities created from reporting rock-related information and the demonstration of technical competence. These opportunities could be applied toward the goals of risk management, value creation, sustainability, and growing investor confidence. • The motivation that access to relevant geoscientific data is supported through the current regulatory framework; • Various geoscientific data could be retrospectively shared by mining organisations; and • The articulation of a proposition for voluntary disclosure. v Publications as part of this Research The publications that have been prepared from this research include: 1) The reporting of geotechnical data, uncertainty, materiality for hard rock mining operations. Additional publications that have been drafted and are being finalised, include: 1) Mandatory Codes of Practice in the South African Mining Industry. 2) An overview of legislated and regulated elements regarding ‘competency’ in mining operations. 3) An overview of the elements of section 54 and section 55 notices issued to South African mining operators. 4) What does it matter? An exploration of the language used in assessments wih regard to characteristics of risk-related elements. 5) Mining disasters and the resulting inquests undertaken to investigate and determine cause and responsibility. 6) An overview of the South African Mines Reportable Accidents Statistics System (SAMRASS). 7) 8) Mines Rescue Services of South Africa. 9) A comparison of mining rock-related, higher education learning programmes in South Africa, Australia, and Canada. 10) A comparison of the mining geotechnical elements required for reporting as part of the SAMREC Code, NI43-101 and JORC Codes. 11) An insight into various ‘risk reports’ generated by organisations across the globe, with interest in mining.Item Mergers and Acquisitions by South African Mining Companies as a Strategy to Create Value for Shareholders: Evidence Between 1998 and 2022(University of the Witwatersrand, Johannesburg, 2025) Makhado, Nyadzeni; Mtegha, HudsonThe objective of this study was to determine if acquiring of assets by mining companies has been beneficial to the shareholders from 1998 to 2022. This study seeks to answer the null hypothesis stating that transaction announcement does not create cumulative average abnormal return for buying mining companies and does not create value for shareholders. Data for the study was acquired from Standards and Poor’s database and streamlined down to 41 transactions. The samples were then grouped into full sample, diversified metal and mining, gold, precious metals, steel, and 1998 to 2022 five year periods sample grouping. This quantitative research uses an event study that serves as a statistical method to evaluate the influence an event has over the value of a company. The event window includes buying company share price starting at 250-days preceding the announcement date and 10 days after. Then, 21 days (-10, 0, 10), was strategically chosen to capture results 10 days before and after the event announcement. This method allows the computation of average abnormal returns and cumulative average abnormal returns. The results are presented using a structure that includes: sample descriptive statistics, average abnormal returns and cumulative average abnormal returns, cumulative average abnormal returns weighted, solver (to minimise sample variance), correlation, covariance and efficient frontier (to plot a graph which conservative to aggressive investors can extract return on investment). All samples cumulative average abnormal returns were plotted on a graph and on average, it reduces leading up to event day and increases after the event day. The null hypothesis was accepted across all sample groups and the study outcomes indicate that acquirers did not generate statistically significant positive abnormal returns. An opportunity exists for researchers to research gold companies and the value created using a long-term event study methodology.Item Temporal and Spatial Reconciliation at Storm Mountain Diamonds Mine (Pty) Ltd(University of the Witwatersrand, Johannesburg, 2025) Tukula, Lerato; Thomas, HuwStorm Mountain Diamonds (Pty) Ltd’s Kao Mine has not been consistently achieving its production and grade targets, schedules, and mine call factor compared to the grade control model forecasts. These discrepancies can jeopardise the future of the mine and can lead to inaccurate decision making. Therefore, the aim of this study was to conduct temporal and spatial reconciliation at the mine. This was done to identify sources of variations in mineral resource volumes, tonnages, and grades at the mine. This reconciliation process is crucial for mines as it ensures the alignment of predicted and actual mineral resource extraction. The study was conducted for a period from September 2022 to August 2023. Various data collection methods were used including truck counts, plant weightometer, advanced vehicle analysis, and global navigation satellite systems to do the reconciliation process. Data such as truck tallies, face mapping, density measurements, exploration drilling data and monthly survey data were utilised in this research. It was found that the mine’s performance during the review period was below expectations. Average temporal and spatial compliance were found to be 8% (between tally and survey measurements) and 75%, respectively. September 2022 notably recorded the lowest spatial compliance of 44% primarily due to low equipment availability averaging 75%. Also, over- and under-breakages of up to 5m from the design were observed. This temporal and spatial underperformance was broadly caused by several reasons including poor blasting practices, unpredictable rainfall, human error and poor understanding of the orebody. It is recommended that the mine consider using more advanced survey equipment and data analytics technologies to collect and analyse data more accurately. The mine should also improve its accounting practices including spillage management on belt conveyors, maintaining low stockpile levels, regular calibration of weightometers and shifting to daily operational planning. It is also recommended that the mine must involve all relevant stakeholders in the reconciliation process to promote a culture of continuous improvement and accountability.Item Unravelling the Past for a Safer Future: How Historic Rock Mass Classification Data Compare With Slope Performance Monitoring Data(University of the Witwatersrand, Johannesburg, 2025) Pretorius, Mornè; Stacey, DickThis research investigates the correlation between empirically derived monitoring threshold values and actual slope monitoring data in open-pit mining, focusing on the Gamsberg Mine in South Africa. The study analyses two slope failure events within a schist layer. The goal was to quantitatively analyse available datasets to determine their relationship and evaluate whether empirical predictions can accurately forecast real-world rock mass behaviour in open pit slopes. Rock mass classification data (RMR and GSI) from borehole logs were compared with real-time deformation measurements from slope stability radar. The methodology involved extracting relevant geotechnical data, calculating rock mass modulus and strain values, and comparing these with actual recorded deformations. Statistical analysis utilizing Z-tests and visual representations was employed to assess the correlation. The study reveals a significant alignment between empirical predictions and actual measurements, with both events falling within one standard deviation of the empirical dataset's mean. This validates the utilization of empirical methods for initial deformation threshold estimations in slope stability monitoring. The research underscores the importance of continuous calibration with site- specific data while validating empirical methods. It contributes to improving risk management and operational efficiency in open-pit mining by bridging the gap between theoretical models and real-world slope behaviour. Future research should focus on expanding the sample size, investigating environmental factors, and integrating emerging technologies to enhance prediction accuracy. These steps will further refine the application of empirical methods in slope stability monitoring and improve overall mining safety and efficiency. This study provides valuable insights into the practical application of empirical deformation thresholds in open-pit mining, offering a foundation for more accurate and reliable slope stability assessments. The findings have implications for iv enhancing safety protocols, optimizing resource extraction and improving overall operational efficiency in the mining industry.Item The Effect of Improved Mineral Resource Management on the Net Present Value of the Camutue West Kimberlite Diamond Deposit in Angola(University of the Witwatersrand, Johannesburg, 2025) Pienaar, Philip DanielAngola is rated as a high-risk investor destination, fueling a high cost of equity rate. Bank loans are not easily secured for exploration programs with no proof of return from an established Diamond Resource. The Camutue West kimberlite was mined without a properly developed Diamond Resource model, and no investment was made in exploration drilling. The resource model was extrapolated to avoid capital spending. The exploration drilling program initiated in 2023 provided an opportunity to compare the extrapolated model to the actual result. It provided an opportunity to determine the value of the risk in avoiding capital spending compared to the cost of exploration drilling. Diamond valuation is a unique process that requires the final product to be in high quantities to determine the expected recovery price. Access to such samples could come at a very high cost if not exposed on the surface. This motivated the research to apply open pit optimisation techniques to assist exploration programs in adding value. Capital spent on the resource estimation, drilling and sampling program has been proven to increase the mine's value compared to the orebody extrapolation method. This proved that there was no replacement for a high- quality resource estimation, drilling and sampling program. Open pit optimisation techniques can be applied to reduce exploration drilling depth, assisting with quality control standards. These techniques also help generate earlier revenue for added value to the mine. Diamond mining companies must investigate the best techniques and drilling equipment to ensure high-quality exploration results. The success in achieving an optimal NPV result is highly dependent on an accurate geological model. Shareholders need to commit to proper exploration programs to achieve the best results for all stake holders involved.Item An Investigation into the Sunday Work Prohibitions in the South African Mining Industry(University of the Witwatersrand, Johannesburg, 2025) Phefo, Omphemetse; Ramontja, ThibediThere have been different views on implementing Section 9 of the 1956 Mines and Works Act, which prohibits certain mining activities on Sundays in the South African mining industry. Mining companies must apply to the department responsible for mining for ministerial permission to perform any work on Sunday. However, some people believe that the prohibitions should be abolished or reviewed. Accordingly, the primary research objective was to develop evidence-based policy proposals to regulate Sunday work prohibitions in South Africa’s mining industry. The research used quantitative methods to examine historical trends and possible implications associated with granting ministerial permissions and analysing solicited views on the prohibitions from stakeholders in the mining industry. Additionally, qualitative methods were used to gather and analyse data through literature review, case studies and interviews. Literature review showed that Sunday work prohibitions have their origins linked to Sunday work restriction laws passed by countries that made Christianity part of the State's administration. Furthermore, the results revealed that valid ministerial permissions increased yearly from 50 in 2015 to 127 in 2022. Analyses of trends and correlations between the valid annual ministerial permissions and safety, production and employment were undertaken to determine the impact of the permissions on these parameters. The results show that an increase in ministerial permissions does not negatively impact safety in most mines. The findings are consistent with the case studies' findings. Similarly, regarding production, most sectors' annual output increased with the increasing number of annual ministerial permissions. The results also show that an increase in ministerial permissions assisted a large mining industry sector in increasing employment. The case studies showed that the reasons for applying to work on Sundays were mainly related to the desire to increase production and address financial sustainability. Interviews revealed that most participants support the retention of Sunday work prohibition but would like the legislation to be reviewed through a consultative process. The international review’s investigation does not v indicate the institutionalisation of Sunday work prohibitions in the mines through legislation. Therefore, it is recommended that the government be aware of the increasing number of applications for ministerial permissions to work on Sundays, consider increasing capacity to address the increase, continue granting the permissions, and initiate a process to review the Sunday work legislation. The research will assist tripartite stakeholders, including policymakers, to make informed policy decisions.Item Investigating the Introduction of Fuel Cell Technology in Underground Mining Equipment(University of the Witwatersrand, Johannesburg, 2025) Mokgethi, Lesego; Twala, PontshoFossil fuels, which are major energy sources, have harmful effects on the environment, and their continued use contributes to global warming and climate change. Moreover, diesel combustible engines in underground mining machinery emit noise, diesel exhausts, and heat during operation, creating an unfavourable working environment. Diesel particulate matter has been classified as a human carcinogen, and occupational exposure limits have already been established in other countries and are anticipated in South Africa. The research investigated the introduction of hydrogen fuel cell technology in underground machinery, particularly the diesel load haul dump machine, to mitigate harmful emissions during their operation and promote the use of renewable energy. The objectives of the study entailed assessing the effects of diesel exhausts in underground working environment, as well as actions taken to reduce emissions. The study also looked at the key aspects that need to be considered to support the application of fuel cell technology in mining operations, constraints affecting their adoption and status of existing regulations and policies. The application of hydrogen fuel cell technology in the mining industry would promote the beneficiation of platinum and other minerals in South Africa, further contributing to economic development and growth. The successful implementation of hydrogen fuel cell technology would also result in a healthier working environment for underground employees and would be a step towards achieving a carbon-free environment. The study employed a mixed-method approach. Data was collected through semi- structured interviews conducted with relevant subject matter experts within the mining industry. Measurements of the operating environment were taken, and the maintenance requirements of the current internal combustible engines and site visits to different sections of the case study mine were conducted. Diesel fuelled machines have harmful effects on the working environment and contribute to global warming. Measures put in place to reduce effects of diesel exhausts affect productivity and are mostly human dependent such as effective use of personal protective equipment. During the design stage, key considerations iv such as the environment, performance and emissions requirements must be studied. Prior to implementing fuel cell technology in underground mining equipment, sufficient testing must be done to ensure reliability and reduce repair costs. To ensure the smooth implementation of Hydrogen Fuel Cell (HFC) in underground equipment, adequate assessment of the skills and training will be required. Existing regulations and policies must be reviewed, and new policies must be introduced to support hydrogen fuel cell technology and to increase investment in the South African hydrogen economy. With the worldview shifting towards a sustainable environment and development, all research and development that supports renewable energy is critical. Research and development to reduce capital costs of HFC technology through improved processes and large-scale production must be done.Item A Just Energy Transition: Challenges and Benefits in the South African Coal Mining Industry(University of the Witwatersrand, Johannesburg, 2025) Mamabolo, Diana; Smith , GordonThis research report investigates the transition to renewable energy (RE) in South Africa, focusing on the challenges, benefits and opportunities involved in shifting from a fossil fuel-dependent energy system to sustainable energy sources like solar and wind. The study explores how various stakeholders, including employees from Seriti Resources, Thungela Resources, Glencore, Eskom, the Department of Mineral Resources and Energy (DMRE) and community members in coal-dependent regions, perceive the potential of renewable energy and the implications of such a transition on the country’s economy, energy security, social welfare, and environmental goals. The research employs a qualitative approach, gathering data through semi-structured interviews with community members (4) and industry experts (14), including engineers, environmental specialists, and managers working across the energy, mining, and regulatory sectors. Thematic analysis was employed to identify recurring themes from the interview data. Key themes identified included the national energy status, processes of RE transition, opportunities and challenges associated with the transition and its social impacts. Research findings reveal that, while renewable energy offers environmental sustainability and potential to reduce load shedding, several significant challenges need to be addressed. These include the high costs of renewable energy, potential job losses in coal-dependent regions, and the unreliability of solar and wind energy in providing a continuous power supply. Furthermore, participants highlighted the lack of political leadership and regulatory frameworks as major barriers to the successful implementation of renewable energy projects. The findings are based on the analysis of interview content, as highlighted by participants during the qualitative interviews. The report concludes that South Africa’s energy transition must be approached with careful planning, considering the socio-economic implications of moving away from fossil fuels. Recommendations include promoting an energy mix strategy, fostering government-led initiatives to build grid capacity for renewables, increasing public awareness of career opportunities in the renewable energy sector, and establishing policies that attract foreign and local investments. The report suggests that a gradual, well-executed transition, with clear strategies to mitigate job losses, ensuring energy security, and addressing social concerns, is essential for South Africa to achieve a just and sustainable energy futureItem Mismatch Between Mine Prosecution Rates in Terms of the Mine Health and Safety Act and Recommended Prosecution Outcomes of Mine Fatality Inquiries(University of the Witwatersrand, Johannesburg, 2025) Kekana, Glentine Tshegofatso; Twala, PontshoOccupational Health and Safety (OHS) in South African mines has vastly improved from the early 1900 towards democracy and post-democracy. In the decade between 1984 and 1994, a total of 7400 employees lost their lives in mine accidents. Whilst in the latter decade between 2012 and 2022, 844 fatalities were reported, showing a reduction of 88.6%. The landmark accident of the Vaal Reefs Mine Disaster in 1995, where 104 employees lost their lives in the line of duty became a catalyst to investigate the status quo of OHS at mines. There was a commission of inquiry appointed by the former state president Nelson Mandela and the most crucial recommendation that came out of that inquiry was the promulgation of the Mine Health and Safety Act, Act No. 29 of 1996 (MHSA). The overarching aim of the MHSA is to protect the health and safety of employees and other persons at the mines. This is supported by several objectives, one of which seeks to provide for effective monitoring systems and inspections, investigations and inquiries to improve health and safety. The MHSA makes provision for mine fatal inquiries to be conducted and if gross negligent behaviour is found, sections 91(1) and 86(1) of the MHSA make provision to recommend prosecution. Despite MHSA provisions, mine prosecutions have been low. The study aim was to establish reasons for the low prosecution rate and understand aspects that need to be considered to achieve successful mine prosecutions. The study was conducted using a combination of different research methods for data collection and analysis. Qualitative methods comprised of surveys, interviews, and document review. Key informant interviews were conducted with several key stakeholders including government, industry, trade unions and others. The quantitative data involved the collection of health and safety statistics and prosecution data. This data was used to establish OHS performance and identify trends in mine prosecutions. The findings on OHS performance revealed that there were repeat mine fatal accidents, and the leading causes were falls of ground, transport and machinery, fires and general types of accidents. The key findings on prosecutions indicated that between the period 2016 to 2020, there were no successful mine prosecutions meted out. This has been attributed to several factors including shortcomings of the existing legal framework and procedural practices, lack of resources and capacity from the mine’s inspectorate and national prosecuting authority, the quality of inquiry reports and limitations thereof, poor collaboration between state institutions as well as political interference. The areas of improvement raised in the study include the need for legislation to become more detailed with prescribed minimum standards. There is also a need for training to build the capacity of the inspectorate and national prosecuting authority. The return of mining courts or a tribunal was also recommended to improve prosecution outcomes and to ensure that a better relationship is established between state and other key institutions.Item Impacts of Acid Mine Drainage on the Kromdraaispruit System(University of the Witwatersrand, Johannesburg, 2000-07) Kyeyune, Silvia Kataliwa; Limpitlaw, DanielThe area of study, the Kromdraaispruit system, is located in the Mpumalanga Province of South Africa. The system consists of both a stream and a wetland, which are receiving environments of treated acid mine drainage emanating from the flooded underground coal workings. The mine management noted that, even after the water from the underground workings had passed through the liming plant, acidic seeps 200m downstream were polluting it. Sampling of the Kromdraaispruit system was done over a 12-month period. Different parameters including pH, EC, Total Dissolved Solids (TDS), Suspended Solids, Total Alkalinity (TAIK), Acidity, Chloride, Sulphate, Calcium, Magnesium, Sodium, Potassium, Iron, Manganese and Aluminium were analysed. The analysis revealed an acid mine drainage problem with maximum measured concentrations of >2000 mg/l S02, 15.84 mg/l Mn, 580.90 mg/l Ca, 49.14 mg/l Mg, 13.41 mg/l K and 98.25 mg/l Fe. The lowest pH in the region was pH 2.97 from the seeps around the liming plant area. Using different modelling packages like ILWIS and STASOFT, it was found that, compared to the acidic seep, the groundwater intercepting the stream at four points, one point along the liming plant stream and three in the wetland, did not have as big an impact on the concentration of some determinants like pH. In the Kromdraaispruit wetland, the wetland sediments act as a sink for contaminants, generally improving the quality of the water flowing through it. The concentration of some determinants passing through the wetland, such as SO, Mn, Ca, Mg, K and TDS, decreased. It was also noted that the efficiency of the wetland was greatly reduced by the high discharge of accumulated salts that simply flushed through it. In most cases, determinants like SO, Mn, AI, Ca, TDS, EC and pH decreased, but not to concentrations complying with the permissible levels stipulated by the Department of Water Affairs and Forestry. Due to the addition of lime downstream of the liming plant, a suspension of “yellow buoy” formed in the wetland. This decreased the potential of the wetland to reduce pollution. Soils were collected at different sites around the study area during the rainy and dry seasons. Laboratory analysis involved determination of total anions and cations, Sodium Adsorption Ratio (SAR), saturation, pH, electrical conductivity (EC) and the concentrations of Ca, Mg, K, Na, SO, F, CI, NO, NO and available PO. From the results obtained it was noted that the soils did not contribute to nor ameliorate acid mine drainage in the Kromdraaispruit system. This is because South Africa is an arid region and migration of ions in the soil to cause any significant impacts is slow. This study discusses the implications of these observations for the monitoring and management of the polluted system.