A comparison of ordinary and simple kriging on a PGE resource in the Eastern limb of the Bushveld complex

The selection of an appropriate estimation method is one of the fundamental decisions in resource estimation. The effects of selecting an inappropriate estimation method can lead to ± 50% error in the estimate (Dominy et al., 2002). In selective mining, for example it is the mining block estimates that determine which of the ore blocks are to be mined and processed and which of the ore blocks are waste. The choice of the estimation method amongst others is based on the geology and complexity of grade distribution within the deposit. For example polygonal estimation methods are suitable for producing a volume weighted global mean grade, and in this estimation method there is one fixed and biased answer. The inverse distance method is unbiased but does not minimise the estimation variance, while kriging is subject to certain conditions, such as providing the best estimate possible by a linear combination of the available weighted data as well as minimising the error variance of the estimate. This dissertation presents a detailed study of the application of two linear geostatistical estimation techniques; Ordinary and Simple Kriging. Included in this study is a detailed discussion on variography and its necessity in resource estimation. The theory of kriging as well as the kriging equations is discussed in great detail. The differences between Ordinary and Simple Kriging estimation techniques are drawn from this study by the consideration of the kriging variance, kriging efficiency, kriged estimate, kriging neighbourhood as well as the block variance. The suitability of the application of both Ordinary and Simple Kriging estimation techniques is highlighted by this study. The two techniques are applied on a PGE (4E) deposit from an undisclosed locality due to confidentiality. This dissertation highlights the differences that are not discussed in most literature between Ordinary and Simple Kriging and the way that these techniques influence the outcomes of mineral resource estimation

Dust deposition impacts at a liquidated gold mine Village : Gauteng province in South Africa

Abstract: The windy season brings numerous community complaints for gold mining companies situated in theWitwatersrand due to windblown dust from partially rehabilitated tailings storage facilities (TSFs). For communities encroaching onto TSFs, windblown dust is perceived as a health hazard and an environmental challenge. In a study conducted in 2017 by the Lawyers for Human Rights, the community of a gold mine village perceived tailings storage facility 6 (TSF6) and other surrounding tailings storage facilities which are partially rehabilitated to be a health and socio-economic threat. Since 2013, when a nearby gold mining company was liquidated, this community has been complaining about dust fallout. To validate the claims made by the community this paper reports on the dust deposition impacts, and respiratory illnesses risk posed by wind-blown generated dust. The study conducts an air quality assessment using dispersion modelling of windblown dust. Surface material from the TSFs was sampled, analysed for silica and heavy metal content using X-ray fluorescence (XRF) and inductively coupled plasma-mass spectrometry (ICP-MS) respectively. This study finds that PM10 dust fallout, high in silica and uranium content, could potentially pose health threats to the surrounding community. The study further shows that dust deposition is the highest in July–October, with TSF6 posing a nuisance while TSF1 represents a potential health threat owing to its particle size distribution for the surrounding gold mine village community. Potential receptors of the air pollution by dust in this study area include neighbouring property owners, business owners of the nearby shopping centre, the school and the clinic. This study further finds that sudden mine closure due to mine liquidation results in unrehabilitated tailings storage facilities which exacerbates dust deposition

A critical review of the impact of South Africa’s mine closure policy and the winding-up process of mining companies

Abstract: Background: Most mining operations are viable for a period of 30 years, depending on the mineral extracted and the available reserves. Whilst the expectation is that mines will continue uninterrupted until the planned period is complete, unscheduled closure can occur. Sudden and unplanned mine closure can result in immediate environmental and social impacts. In South Africa, the challenges of mine closure are exacerbated by unexpected sudden closures owing to winding-up and business rescue processes. The literature is inconclusive regarding these issues and there is poor integration of affected communities by mining operations. Aim: We reviewed South Africa’s legal frameworks relating to mine closure, the winding- up of gold mining companies and the impact of sudden closure on the environment and communities. Method: This review built on and extended previous systematic reviews. We focused on the regulation for fi provisioning for prospecting, mining, exploration and rehabilitation. Two examples of gold mining companies that were closed prematurely were examined. We also reviewed the mine closure and environmental policies of other countries, notably Australia and Canada and noticed similarities to South African policies. Results: Differences are evident in the enforcement of compliance in Australia and Canada, which are more proactive in dealing with the challenges of winding-up and its impacts. Conclusion: South Africa could adopt these countries’ models to enforce compliance and proactivity regarding sudden mine closure. One recommendation is to establish a fund for immediate rehabilitation in such cases as part of the temporary mine closure framework

Perceptions of external costs of dust fallout from gold mine tailings: West Wits Basin

Mining is important for the South African economy, as it is for many developing African nations. In 2017, mining was reported to contribute 6.8 % to the South African GDP and provided more than 460, 000 jobs. Though mining adds an enormous amount of value to the country, it has significant impacts on the environment and the socio-economic factors of society. The well-documented environmental impact of mining operations on surface and groundwater systems, known as Acid Mine Drainage (AMD), is just one of these environmental impacts. There are also other impacts such as the pollution of agricultural soils, the creation of sinkholes and air pollution. For example, airborne dust remains a persistent problem in South African urban areas due to the climatic conditions, extensive surface mining, unrehabilitated tailings storage facilities and mineral processing. However, very little is reported on the socio-economic costs that are due to poor environmental management. Some scholars assert that despite the Mine Health and Safety Act, deposition monitoring guidelines and national dust regulations, South Africa still experiences persistent dust problems, especially in coal and gold mining districts. This paper investigates the effect of gold mining dust pollution in and around a Gold Mining Village, in South Africa. A quantitative and qualitative approach was used, where a questionnaire and interviews were conducted to examine the Gold Mine Village perceptions on dust pollution and their socio-economic environment. This paper further examines how poor and premature mine closure by liquidation results in unrehabilitated mine tailings and how this has significant impacts on the socio-economic status of individuals and surrounding businesses. The community being investigated in this study, perceives the dust fallout impact to be a socio-economic threat. The paper finds that the community believes it incurs medical financial expenditures due to treating respiratory-related diseases triggered by dust fallout

The Potential Health Costs of PM10 Impacts on a Gold Mine Village, during Company Liquidation: An Analysis of 2013–2017

Windblown dust from tailings storage facilities (TSFs), particularly in towns with liquidated mining companies, exacerbate air pollution. Companies of suddenly closed mine operations evade the responsibility of environmental and socio-economic care required by law. It is common for suddenly closed mines to have poorly rehabilitated TSFs which become a significant source of pollution by dust for the surrounding communities. There is strong evidence that acute exposure to high levels of air pollutants causes significant mortality and morbidity. However, very few studies have estimated the externalities of PM10 emanating from gold TSFs especially when a mine closes suddenly owing to company liquidation. By exploring the externalities of PM10 arising from wind erosion of suspended particulate matter from TSFs, this study fills an existing gap in the literature. A ‘bottom-up’ approach was implemented in this study following the External Energy (ExternE) project, and a gold mine operation that was liquidated between 2013 and 2017, was used as the case study. In this study, the externality of PM10 estimated was the cost of illness focusing specifically on respiratory-related illnesses. The results showed that the estimated cost of illness associated with PM10 inhalation was a total of R 5,560,022 including assessments of both neighboring Wedela and the Gold mine village based on the threshold concentration set by the South African National Ambient Air Quality Standards (NAAQS) guideline and R 66,092,760 when considering the Fund for Research into Industrial Development Growth Equity (FRIDGE), Airshed and Infotox. Thus, it was concluded that air pollution by windblown dust from partially rehabilitated TSFs has the potential to significantly affect surrounding mining communities’ socio-economic status through poor health and the costs thereof

A critical review of the impact of South Africa’s mine closure policy and the winding-up process of mining companies

Background: Most mining operations are viable for a period of 30 years, depending on the mineral extracted and the available reserves. Whilst the expectation is that mines will continue uninterrupted until the planned period is complete, unscheduled closure can occur. Sudden and unplanned mine closure can result in immediate environmental and social impacts. In South Africa, the challenges of mine closure are exacerbated by unexpected sudden closures owing to winding-up and business rescue processes. The literature is inconclusive regarding these issues and there is poor integration of affected communities by mining operations. Aim: We reviewed South Africa’s legal frameworks relating to mine closure, the windingup of gold mining companies and the impact of sudden closure on the environment and communities. Method: This review built on and extended previous systematic reviews. We focused on the regulation for financial provisioning for prospecting, mining, exploration and rehabilitation. Two examples of gold mining companies that were closed prematurely were examined. We also reviewed the mine closure and environmental policies of other countries, notably Australia and Canada and noticed similarities to South African policies. Results: Differences are evident in the enforcement of compliance in Australia and Canada, which are more proactive in dealing with the challenges of winding-up and its impacts. Conclusion: South Africa could adopt these countries’ models to enforce compliance and proactivity regarding sudden mine closure. One recommendation is to establish a fund for immediate rehabilitation in such cases as part of the temporary mine closure framework

The Potential Health Costs of PM₁₀ Impacts on a Gold Mine Village, during Company Liquidation: An Analysis of 2013–2017

Windblown dust from tailings storage facilities (TSFs), particularly in towns with liquidated mining companies, exacerbate air pollution. Companies of suddenly closed mine operations evade the responsibility of environmental and socio-economic care required by law. It is common for suddenly closed mines to have poorly rehabilitated TSFs which become a significant source of pollution by dust for the surrounding communities. There is strong evidence that acute exposure to high levels of air pollutants causes significant mortality and morbidity. However, very few studies have estimated the externalities of PM10 emanating from gold TSFs especially when a mine closes suddenly owing to company liquidation. By exploring the externalities of PM10 arising from wind erosion of suspended particulate matter from TSFs, this study fills an existing gap in the literature. A ‘bottom-up’ approach was implemented in this study following the External Energy (ExternE) project, and a gold mine operation that was liquidated between 2013 and 2017, was used as the case study. In this study, the externality of PM10 estimated was the cost of illness focusing specifically on respiratory-related illnesses. The results showed that the estimated cost of illness associated with PM10 inhalation was a total of R 5,560,022 including assessments of both neighboring Wedela and the Gold mine village based on the threshold concentration set by the South African National Ambient Air Quality Standards (NAAQS) guideline and R 66,092,760 when considering the Fund for Research into Industrial Development Growth Equity (FRIDGE), Airshed and Infotox. Thus, it was concluded that air pollution by windblown dust from partially rehabilitated TSFs has the potential to significantly affect surrounding mining communities’ socio-economic status through poor health and the costs thereof

South Africa’s electricity disaster is an air quality disaster, too

No abstract available.http://www.cleanairjournal.org.zaam2024Geography, Geoinformatics and MeteorologySDG-11:Sustainable cities and communitie