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A monthly publication devoted to scientific transactions and specialist technical topics is unlikely to be on the priority reading list of the majority of the mining and metallurgical community. But it is the ambition of the Publication's Committee to make the Journal of much wider interest to our general membership from technician trainees to mine managers to CEO's of our constituent companies. It is to entice general readership that some 1200 words of valuable space are devoted to the Journal Comment each month. This is intended to highlight some of the features and impact of the papers to excite and activate attention.

To entice this preliminary glance before confining the publication to the book shelf or even the wpb, the author has to call on a large measure of journalistic licence in style, titles and quotations. It is essential to be spicy, controversial and even provocative to separate it from the abbreviated authoritative but necessary scientific style of the bulk of the contents.
The Journal Comment aims to be an enticement to dig into some important feature of the papers in the issue. For this reason it has been decided to include it as a separate item on the Institutes Web Site. This might provoke those who enjoy twittering, blogging and googling to submit comment and criticism, all of which will be welcomed and responded to. At least it is proof that somebody has read it.
R.E. Robinson

The Wave

Q.G. ReynoldsDuring the COVID-19 pandemic we’ve heard a lot about waves. First waves passing, second waves arriving, and how many such waves we might still have to endure in the future. Despite all the talk, each wave seems to catch us largely by surprise and we are too frequently left in a shell-shocked state, wondering ‘How on earth could things get so bad so fast?’ The problem here is that epidemics are an exponential growth phenomenon, and human beings are notoriously bad at grasping the import of exponential behaviour. Our internal forecasting and world-modelling instincts like to assume that things change linearly, and as a result we find it difficult to prepare ourselves for the true impact of an exponential event even as our rational minds can see it looming.

Exponential growth is linked to another part of the modern human experience, namely the computing power of our digital machines. This means that their ability to solve any particular problem passes from laughably impossible to difficult, then to trivially easy in a remarkably short space of time, upsetting and revolutionizing everything in its wake – much like a wave.

The point at which that wave breaks over your industry is determined only by how difficult it is to compute solutions to the mathematics describing it. In process metallurgy we might be forgiven for thinking that our engineering challenges are so vastly complex that traditional workflows will never be replaced by computational alternatives, but it’s only a matter of time. Right now the digitalization tsunami is tiny and easily ignored, but the ripples are building momentum, and recent experiences should warn us that it’s time to prepare, prepare, prepare.

Q.G. Reynolds
Pyrometallurgy Division, Mintek
Process Engineering Department, Stellenbosch University

Diamonds: Source-to-Use, 2020

The Diamonds: Source-to-Use 2020 conference was to have been held at the Birchwood Hotel and Conference Centre during 9–11 June 2020. It was to have comprised 1½ days of presentations/exhibitions and two technical site visits, to Multotech and Epiroc, as well as a beer tasting event at Mad Giant Craft Beers. By early March, we had 21 confirmed papers, including two keynote addresses.

And then, just as elsewhere in the world, our plans were interrupted by the hard lockdown associated with the COVID-19 pandemic. Although the SAIMM is well positioned to undertake virtual conferences, it was decided to rather wait until 2021 to hold a face-to-face meeting. Consequently, a new date of 8–10 June 2021 has been proposed. Given the difficulties of travel and the unknowns of how the pandemic will progress, we are looking at the possibility of holding a hybrid event, whereby delegates and presenters alike can either take advantage of a real conference or enjoy the benefits of virtual attendance.

The effects of the global pandemic have been seen across the entire diamond pipeline, disrupting production and sales as well as the entire downstream cutting and polishing industry. With no-one knowing how long these impacts will be with us, and not having certainly on what the post-COVID scene will look like, the theme of the conference – Innovation and Technology – is still appropriate, if not more so. We, as the global diamond community, will certainly have to apply our minds to the changed landscape and come up with new ways of doing business. We expect that the 2021 Diamonds: Source to Use Conference will attract many stimulating papers on the new ‘normal’ within the diamond industry, which may never look the same as it has in the past. We look forward to this new challenge with excitement and more than just a little trepidation.

journalcomment02112020

In order to show our appreciation for the effort that many of the presenters dad made to get their papers completed and peer-reviewed in time for the original conference, it was decided to give them the opportunity to publish in this edition of the SAIMM Journal. The papers in this volume highlight some of the advances made across the range of exploration, mineral processing evaluation, and reporting of diamond projects.

T.R. Marshall

Meeting industry challenges

As we find ourselves in a world dominated by COVID-19, it is clear that the mining industry is not exempted from the impact of the pandemic. The industry will change in ways we cannot yet quite appreciate. This comes on top of the other challenges that mining (and indeed the wider world) is faced with, such as climate change, uncertain trade relations, and the imperatives of sustainable development. The coal mining industry faces a further challenge in that the need to reduce carbon emissions will inevitably lead to a reduction in the use of coal, particularly for the generation of power. It is accepted that the transition to renewable energy will proceed, and that the use of coal will decline in the medium to long term. A transition is needed that will result in security and affordability of electricity supply, while at the same time allowing the industry and all its stakeholders to adjust to the disruptions that such a transition will cause. For this to happen, stakeholders need to find new and innovative ways to operate, and the input of the scientific community is a crucial part of this process. In this edition of the Journal, general papers are published. Some touch directly on the issues the coal industry faces; others more indirectly. All, in their own way, will assist in meeting the challenges the mining industry is faced with.

H. Lodewijks
Coaltech Research Association NPC

Empowering the African minerals industry through diversity and inclusion

Many organizations that launch diversity and inclusion initiatives cite research showing that companies with more diverse teams outperform those with a more homogeneous workforce. According to some of these reports, the inclusion of voices from different geographic, gender, economic, and cultural groups not only creates opportunities for individuals to grow within the company, but also helps the organization to harness the talent and potential for itself, leading to greater profitability and value creation. Therefore, looking at it in simple terms, there is value in embracing diversity and inclusion initiatives in the workforce.

The Southern African mining sector, just like the global mining industry, still faces huge challenges when it comes to gender inclusivity and the creation of a supportive environment for career advancement of not only women but also other workers from diverse backgrounds such as, for example, LGBTQI. Issues such as gender disparity, safe spaces in the workplace, protective equipment, sanitation facilities, pregnancy and child care are but a few challenges that continue to plague the sector. There is thus a great need for strategies for advancing womens’ representation and encouraging decisions that are in the best interests of a diverse workforce in the mining industry.

In most cases, diversity and inclusion are often treated as a single initiative owned exclusively by the human resources section of each organization. However, for real change to happen, leaders of the mining industry need to not only buy into these initiatives, but also embrace the value of belonging. It is only when this happens that we will witness a significant change in the mining landscape. The industry must also realize that sticking to quotas does not mean inclusion; it’s only compliance and not commitment. The industry needs to go beyond that. Identifying individuals, creating safe spaces for them, providing support for them to grow into their roles, and creating conditions that promote inclusion on a daily basis will ensure that such initiatives are not once-off, but are long term, which would be of more benefit to mining companies.

The SAIMM as a professional organization that represents the needs and interest of mining professionals in southern Africa also has a role to play in driving such an agenda. And as such, the Diversity and Inclusion in the Minerals Industry (DIMI) Committee was initiated to raise awareness on these issues and to create platforms for discussion that can lead to the development of strategies for advancing and encouraging decisions that are in the best interest of a diverse workforce. The Committee is made up of dynamic male and female, emerging and experienced professionals from both industry and academia, who are all passionate about seeing positive changes in the minerals sector.

The Committee has held a number of talks at local universities to raise awareness among students and sensitize them particularly to issues related to gender inclusivity and safe spaces within the mining industry. The Committee has also hosted a workshop focusing on challenges and strategies for mentoring and retaining women in the mining industry. A webinar series given by highly notable speakers from within and outside the industry is scheduled for the month of August 2020, to celebrate Women’s Month. The series will cover talks on a weekly basis touching on diverse issues such as gender inclusivity in the workplace, creating a positive environment for diversity, conquering inner fears, developing a growth mind-set, and workplace strategies for mental health. The Committee is also planning to host the first-ever SAIMM conference on diversity and inclusion in the mining industry in August 2021.

The Committee has also been looking at establishing collaborations with partners who are keen to enhance the diversity landscape and cause in the mining industry. Informal collaborative partnerships have been established with the Minerals Council South Africa and Women in Mining South Africa (WIMSA). It is expected that all these strategies and activities will go a long way in catalysing a positive change in the mining industry.

S. Ndlovu
DIMI Chairperson

Focus on the Student Edition

‘It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness, it was the spring of hope, it was the winter of despair, we had everything before us, we had nothing before us …’ – the opening lines to A Tale of Two Cities (1859) by Charles Dickens. And I say Amen to that!

Those words written 161 years ago resonate across nations as we struggle against the COVID-19 pandemic and a ravaged world economy. Gold and palladium at record levels – coal and zinc bottoming. Lives or livelihoods – I would not like to be the decision-maker having to choose between these options in South Africa with 14 mineworkers having died from COVID-19, and with nearly 3000 cases within the sector having been recorded at the time of writing. It is apparent that the balance, even in the world’s wealthiest countries, has tipped in favour of livelihoods over lives.

My heart says that this decision is insensitive to the pain of families who have lost a cherished parent or grandparent, or have to confront the anguish of entering the workplace and worrying about the risk of infection, but my brain says the alternative is no better. Without going back to work and earning money to buy food, many will face the spectre of malnutrition affecting the youngest and weakest within their families. A similar dilemma is facing us regarding the reopening of schools and universities. Opening will spread the virus, but remaining closed will produce a generation of deprived students who will struggle to catch up – probably for the rest of their lives. Hoping that home schooling or online learning are viable alternatives ignores the fact that these options are really open only to families with well-educated parents and/or with the financial means to purchase electricity, computers, and bandwidth, and will inevitably perpetuate and grow existing inequalities in our society.

This copy of the Journal is the Student Edition, containing the research output of students completing their final year of their chosen engineering course at local universities in both mining and metallurgical disciplines. Of the seven papers, three are on mining topics, and four on metallurgical topics, and there is no common theme among the papers. As members of the SAIMM, we can take some pleasure in reading the student papers in this copy of the Journal and feeling that the human resource capability required to sustain the mining industry is already in the making. I therefore encourage you to read the papers, or at least the abstracts, to get some feel for the research currently being undertaken at our universities. The research, though published in this copy of the Journal, was completed last year. Given the pandemic and its impact on the student body, I can only hope that we have sufficient papers this time next year to continue the tradition of issuing a Student Edition!

Five of the papers originate from the universities of Johannesburg, Pretoria, and the Witwatersrand, one from North West, and one from Stellenbosch. I don’t place any significance on this finding, as the distribution tends to vary significantly from year to year, depending upon the student body in that year and the selections made on where to publish their papers. I mention this only because I studied at the University of Natal, Durban (now the University of KZN), and I was hoping to see a paper from my alma mater. In my student years, the late 1960s and early 1970s, the departments of Chemistry and Chemical Engineering were positioned side-by-side, and were the last buildings on the south side of the campus before descending to Logan’s bookshop.

The Department of Chemistry, where I studied and graduated with my PhD, has since relocated to the Westville campus. The first-year chemistry course, and a small part of the second-year course, was shared by both departments, so I had many friends in engineering. Most left after 4 years, but I continued my loose association with engineering as I became a laboratory demonstrator for the first- and second-year engineering students in the chemical laboratories. I have since met many of those students who remembered the generally disliked three-hour laboratory afternoons, and recalled that I was intimidating as I stalked the benches looking over their shoulders at their mostly inept attempts to master practical chemistry. Really, me? – Never, you must be confusing me with someone else!!

The Department of Chemical Engineering was dominated at that time by two giants of South African academia and metallurgy: Professor Peter King and Professor Ted Woodburn. I knew of them by reputation only at that time, but I had the pleasure of meeting them later on many occasions in ‘real life’. I would like to quote an extract written by Professor Mike Moys of Wits (but a postgraduate student at Durban around that time): ‘They supported and competed intensely. Allow me to reminisce briefly about Ted. Ted would arrive in the morning in his Mini Minor. Those of you who knew Ted – a very large man – can imagine Ted extricating himself from the Mini! Ted’s other idiosyncrasy was his habit of management by walking around chewing his tie. Ted also had a remarkable laugh which defies description and echoed through the building every now and then. Peter kept his cool!’

Memories linger, and some seem to become more vivid with the passage of time. As Dickens wrote: ‘It was the best of times ...’, or that was what I recall from my student days. Does anyone else remember those days in Durban, or am I alone with these memories? Is it not human nature that our youth was always the best of times? But will this still apply to today’s students growing up in the midst of the COVID-19 pandemic? Perhaps to them, in years from now, looking back, ‘it was the worst of times’. I hope not!

R.L. Paul

New Challenges to be Faced in 2020

The Commentary in the March edition of the SAIMM Journal was entitled ‘Ethical Research and Scholarly Publication in the Mining and Metallurgical Community – A New Era Dawns’. That article covered the meetings held earlier this year between the SAIMM, ASSAf, and SciELO in an attempt to align the SAIMM Journal with the new rules and regulations put in place by the DHET. This article expands on that theme, with the further comment that the New Dawn’, as inferred, has indeed come about in more ways than one could possibly have imagined some four months ago.

The background to the new rules and regulations of scholarly publishing may be found in a number of recent DHET and ASSAf reports, all aimed at improving the quality of South Africa’s accredited scientific and technical journals. In these reports it is stated that ‘it is in the interests of our higher education system and society in general that the quality of research conducted in the system should be continuously improved’.

In the light of the ASSAf requests for the SAIMM Journal to meet those rules, certain amendments to the operations of the Journal have now been implemented. The resulting changes include, for example, the requirement that at least 75% of the papers published in the Journal must emanate from multiple institutions. In this matter, the SAIMM Journal excels as, on average, over 80% of the scientific papers that it publishes are sourced from organizations and institutions in all corners of the world. A further requirement is that more than two-thirds of the members of all Editorial Boards of accredited journals must be comprised of topic specialists from diverse institutions. This proportion has now been met. Of specific concern to the SAIMM was the rule that dual publication of scientific and technical papers is no longer permitted, i.e. a paper published in peer-reviewed conference proceedings cannot be re-published in the SAIMM Journal.

It is under these rules and against these challenges that the Journal of the SAIMM now endeavours to break new ground and seek new horizons, in the following ways.

The first challenge is to speed up the reviewing process of submitted papers in order to meet the requirements not only of the submitting authors, but also to enhance the professional efficiency of the Journal.

In order to improve the current turnaround time, two matters have been introduced: first, a new system of discipline identification has been drawn up incorporating the full spectrum of subjects covered by the SAIMM Journal. Secondly, a panel of key specialists for each of the disciplines has been selected and these will serve to (1) aid in pre-reviewing submitted papers and (2) assist in the selection of appropriate specialists who will undertake the full peer review function. In future, authors will be required to identify the category (discipline) in which their papers fall. This step, along with a double reviewing process, is being instituted in order to shorten the overall reviewing pipeline.

The second challenge is to recognize the limitations of re-publishing papers in the Journal that have previously been published in peer-reviewed conference proceedings. In future, the Technical Programme Committee, working in conjunction with Publications Committee, will review all forthcoming conferences and, on selecting certain conferences, call for papers with the deadline some months ahead of the conference. On receipt, such papers would then be submitted to the Publications Committee for peer review and, if acceptable, published in the Journal prior to the conference. This will ensure full accreditation and financial reward from DHET for academic authors. No such accreditation, and only limited reward, is possible when publishing in conference proceedings.

Calling for themed editions of the Journal is a further step that has been undertaken to meet the third challenge, that of different focused interests in a multidisciplinary organization. In this manner, papers covering topics pertaining to a specific theme would be invited, generally with an honorary guest editor experienced in the chosen field who would work under the guidance of the Publications Committee. A wide range of subjects can therefore be covered without the issue of convening a conference to meet those themes.

The fourth challenge is to consider the nature of the papers when publishing in future. A paper may be presented as a research report, wherein the results pertaining to a specific project are presented as a simple statement of the outcome of an investigation or activity. This presents data in a static, non-combative format. Alternatively, a paper may seek to engender discussion and debate, to introduce new thought processes, and to challenge other authors to create further advancement in specific topics, all in an attempt to achieve higher levels of research and development in the field of choice. Both forms of paper are acceptable in the SAIMM Journal, subject to their level of originality and scientific and technical contribution, but higher impact is achieved when publishing the latter form of paper. A further and third form of paper, namely a comprehensive review of a process, product, theme, or topic, is welcome and indeed desirable if presented appropriately. In this case, a full review of the subject matter is required, including up-to-date coverage of all pertinent prior publications, a detailed critical assessment of previously published works, and the identification of gaps in knowledge, with comment on past, current, and future trends where applicable.

The fifth challenge is the need to come to terms with the world of COVID-19. Part of the ‘new dawn’ includes facing the immediate, if not longer-term, future in the light of the spread of the global pandemic. It is already apparent that the world of education at all levels has been severely impacted. With talk of abandoning the academic year of 2020 and severe uncertainties as to when scholars and tertiary students may return to academic institutions, research and development outputs this year, and indeed any time in the near future, may be severely limited.

Similarly, much in the world of work has changed beyond recognition, including situations in many mining, metallurgical, and related industrial operations. The closure or limited operation of many such entities, along with the severe financial stresses being encountered in most stateowned- entities (SOEs), does not bode well for major research and development in those sectors in the near future. However, taking a ‘glass half full’ approach, it is possible that such conditions may lead to advances in new and more efficient technologies, higher levels of mechanization, and the faster introduction of AI or the Internet of Things (IoT) in order to streamline operations and minimize costs.

Such considerations may well prove to be the lifeline that could pull specific industries and operations through this period. This, however, does not take account of the plight of the many people in industry who will have lost their positions in the course of this major global pandemic. The re-training, re-focusing, and diversifying of previously-gained experience into new and innovative fields may lead to opportunities for the workforce not considered before. Such matters can serve as food for thought and the development of new concepts for the deployment of unemployed personnel in future. Perhaps papers highlighting such innovative developments could find a place in the SAIMM Journal in future.

R.M.S. Falcon

Ethical research and scholarly publication in the mining and metallurgical community – A new era dawns

This commentary provides an overview of an important meeting between the SAIMM, ASSAf, and SciELO held during February 2020. The meeting arose as a result of new initiatives to ensure integrity in ‘research and scholarly publication’, which have been agreed globally and have now been adopted by the departments of Science and Innovation and Higher Education, the National Foundation for Research, and the group representing the universities of South Africa, among others. The purpose of the meeting was to ensure that the SAIMM, and all South African scientific and professional institutions in general, will meet the global principles of ethical research and scholarly publication (ERSP) as adopted by South Africa.

The Institute is aware of these new ERSP ‘rules of engagement’, and as such, the relevant committees are now starting to work through the issues. Such matters will be published in due course. By way of example in the interim, two issues of direct relevance to the SAIMM include (i) the inability to publish papers that have previously been published in formal refereed conference proceedings, and (ii) a strict limit to the proportion of papers (and authors) sourced from any one institution in any specific journal edition. Such rules will undoubtedly impact upon the manner in which papers presented at conferences will be published in future, and on specific themed editions that include papers from a specific source or specific authors. For these reasons, the Publication and Technical Programme Committees are likely to enter into something akin to a new era of operation in order to meet these new principles while still continuing to provide enhanced knowledge and intellectual services to the mining and metallurgical industries and all the major allied disciplines.

Against the background above, it may be of interest to note that the SAIMM Journal is currently a proven and sought-after global publication. Investigations over the past two years have shown that approximately 70% of the papers submitted for publication arise from international sources and from universities and research institutions as geographically widespread as the USA, China, Japan, India, Russia, Pakistan, Turkey, Germany, the UK, Egypt, and Iran. Approximately 300–400 highly qualified and experienced academics and industrial practitioners, both local and international, are active on the panel of reviewers. Approximately 40 to 45 paper are submitted per month, all of which are pre-reviewed monthly prior to the selected ones entering the review process. Twelve journal editions (one each month) are published annually, with editorial and typesetting undertaken in-house.

In these matters, the Journal would appear to be meeting its current goals and the needs of many of its readers. This is best reflected by the resolutions factor i.e. the number of times a paper is electronically opened and read, known colloquially as the ‘hits’ on a paper. Such data is captured monthly by ASSAf and SciELO for all accredited journals in South Africa. Of specific interest to the SAIMM community is the fact that between 15 000 and 16 000 ‘hits’ (i.e. opening and/or reading of papers) are being recorded for the SAIMM Journal per month, with the next accredited journal on the ASSAf list recording 7 000 hits and the remaining accredited journals recording hits in the mid- to lower hundreds. Such results suggest that the SAIMM Journal is widely read and is therefore of significant relevance to its professional community.

However, what remains to be done is to enhance the standing of the Journal to an even higher intellectual status by improving its Impact Factor (IF – a measure reflecting the average number of citations to articles published in science and social journals). This step would lead to enhanced accreditation for those in academe who, by having their research published and cited in the SAIMM Journal, would earn personal academic accreditation as well as acquire funds for their universities (approximately R120 000 per single Journal paper). It is this that the SAIMM seeks to improve in the short term – in addition to implementing the longer-term goals set by ASSAf and SciELO for proven integrity in research and scholarly publishing currently, as is currently being instituted in the country at present. There is much to be discussed and done in the near future. All will be reported in due course.

R.M.S. Falcon

Heavy Minerals Conference 2019

Heavy minerals is a small and often neglected field of mining and metallurgy. However, this industry produces some of the most important minerals and metals of the modern world. Where would we be without titanium for its multitude of uses, zirconium for its ultra-hard properties in zirconia, or the rare earth elements for their plethora of uses in modern technology?

The mining challenges of this industry are somewhat different to traditional hard-rock mining as the mines are almost exclusively surface operations. However, because of that, the environmental, social, and resource challenges of this type of mining have a character of their own. The economics of the industry can be rewarding, but because of the relatively low price of the intermediates the industry has to move large tonnages of material. The processing of mined minerals, although seemingly simple, has many nasty ‘hookers’ such as the effect of the surface properties of the minerals. The effect of atmospheric conditions on surface properties can have significant consequences regarding the recovery and grade of concentrates. In addition to the metallurgical challenges, the issue of radioactivity requires management. Although not at a level to cause any health issues, the levels are significant enough to attract attention from health and safety regulators. The challenges of the industry do not stop there as the end products of this sector often require high-cost and high-technology solutions. In no way can hightemperature chlorination in a gaseous atmosphere be considered straightforward. Similarly, the production of neodymium or samarium for high-powered magnets is not simple, a fact illustrated by the small number of facilities that operate this technology.

The International Heavy Minerals Conference series hosted by the SAIMM is an industry-driven initiative to allow sharing of ideas, technologies, and methods of handling the various challenges. The first conference was in 1997 and was held in Durban, South Africa. At this conference, which was organized by the Zululand and Western Cape branches of the SAIMM, there were 38 papers and over a 100 delegates. This was followed every second year by further conferences in the HMC series. The committees of the Institute encouraged sister organizations in other heavy-minerals-producing countries to participate, resulting conferences being held in Australia (2001), South Africa (2003), the USA (2005), South Africa (2007 and 2009), Australia ( 2011), India (2013), South Africa (2016), and finally this conference in South Africa in 2019.

At the most recent conference, held in Cape Town, there were 19 papers presented covering a wide range of topics including ore reserve evaluation, mining, minerals processing, pyrometallurgy, and mine closure. There were three keynote presentations given at the conference: Learning from Kwale to build Toliara by Colin Bwye, Executive Director at Base Resources; Tronox - to infinity and beyond by Willem van Niekerk, Senior Vice President at Tronox; and Do heuristics influence the mineral sands mining landscape? by Rob Hattingh, CEO at Sierra Rutile. The two-day conference was followed by a site visit to the Tronox Namakwa Sands Plant at Saldanha Bay.

The International Heavy Minerals series of conferences has become established as one of the main sources of collaboration for those in this industry. While not as large as some other mineral resource sectors, the diversity and complexity found in the heavy minerals industry stands on a par with any of the other resource sectors.

 

J.H. Selby
Chairman: 2019 HMC Organizing Committee

The Ninth International Conference on Deep and High Stress Mining (Deep Mining 2019)

The Ninth International Conference on Deep and High Stress Mining (Deep Mining 2019) was held at the Misty Hills Conference Centre, Muldersdrift, Johannesburg from 24 to 26 June 2019. Conferences in this series have previously been hosted in Australia, South Africa, Canada, and Chile. This event, jointly organized by the South African National Institute of Rock Engineering (SANIRE), the Australian Centre for Geomechanics (ACG), and the Southern African Institute of Mining and Metallurgy (SAIMM), was attended by 196 delegates from 19 different countries. Most of the delegates were from Africa (146), but the other continents were well represented; Asia (6), Australasia (12), Europe (22), North America (5), and South America (5).

The Deep Mining series of conferences continues to contribute to our understanding of deep, high-stress mines. Around the world mines are getting deeper and the challenges of stress damage, squeezing ground, and rockbursts are ever-present and increasing.

Mining methods and support systems have evolved slowly to improve the management of excavation damage and safety of personnel, but damage still occurs and personnel are injured. Techniques for modelling and monitoring have been adapted and enhanced to help understand rock mass behaviour under high stress.

Many efficacious and dynamic support products have been developed, but our understanding of the demand and capacity of support systems remains uncertain. During the conference, 33 papers were presented addressing these topics, 11 of which have been selected for this Deep Mining edition of the SAIMM Journal.

Hagan et al. describe testing of rockbolts in full-scale laboratory conditions. This comprehensive approach includes both shear and pull testing, taking the mechanical properties of the rock mass into consideration. Crompton and Sheppard provide some practical insights into the design of resin-anchored tendons, optimizing resin mixing and the resin annulus. A new remote, mechanized bolting system for use in narrow reefs is described by O’Connor and Seritic, which could significantly improve the safety of underground workers. Limitations of South African narrow tabular deep mine layout design criteria are explained by Malan and Jooste and they discuss possible improvements by calibrating with stress measurements and rock mass monitoring. The evolution of mechanized mining and support methods for the wide reefs at South Deep gold mine is presented by Andrews, Butcher, and Ekkerd. Bouzeran et al. describe analyses of rock mass heterogeneity and buckling around excavations, which helps to understand stope drift stability in foliated ground under high stress conditions. Sharrock and Chapula provide a different perspective on similar challenges at CSA Mine, Cobar. Wesseloo presents some insights into seismic hazard and proposes a consistent terminology to avoid miscommunication. The influence of stopes on the seismic source is explored by Linzer et al. Jones et al. describe how underground stope surveys using autonomous drone systems can assist with the understanding of rock mass behaviour and failure mechanisms, which can in turn improve mine planning and design. An approach to big data analytics and artificial intelligence in rock mechanics is presented by McGaughey; this topic is becoming more important as greater quantities geotechnical and monitoring data are collected.

We are grateful to the presenters and delegates for taking time out of their busy schedules to come and share their knowledge and expertise at Deep Mining 2019. The sponsors are also thanked for their generous contributions, as are the organizing committee and technical reviewers. As always, we appreciate the dedication and organizational skills of the SAIMM secretariat.

W.C. Joughin

Rock engineering research and creation of value

This last issue of Volume 119 of the Journal of the Southern African Institute of Mining and Metallurgy is a truly international one, with papers from five continents and one from the Middle East. Authors of the papers are from Chile, China, Iran, Norway, South Africa and the United States. Although this issue is a General Papers Edition, the content shows a rock engineering focus and the topics of most of the papers are relevant to direct or indirect considerations in rock engineering design, which emphasise the importance of rock engineering research. The only paper in which the rock and rock mass have no relevance is the metallurgical paper dealing with high-carbon ferromanganese and silicomanganese.

Three of the papers deal directly or indirectly with risk. The analysis of seismic event return periods in South African gold mining areas has relevance to the risk of occurrences of rockbursts; and there is an interesting comparison with earthquake event occurrences in Southern California.

The use of the Analytic Hierarchy Process (AHP) to determine confidence levels in the selection of longwall coal mining methods is effectively a risk evaluation process. AHP could also be used to assess the potential for value creation. The paper dealing with the improvement in the definition of geotechnical design sectors in open pit slope design is specifically risk-based. As a result of the research in this paper, significant value was unlocked at the mine, as stated in the company annual report: an annual increase in the NPV of R10 billion ($680 million), corresponding with an additional 50 million tonnes of ore.

Four of the papers deal with properties of rocks and rock masses: laboratory triaxial tests were carried out to determine the effect on rock strength of roughness and orientation of discontinuities. Coincidently, these topics are also dealt with in the risk-based paper. Static and dynamic testing of rock samples was carried out to determine the effect of water content and loading rate on rock strength and deformation properties. Such tests are important because ‘real’ conditions in mines, tunnels and other excavations usually involve moisture contents substantially different from those applicable in standard laboratory tests. The paper dealing with quantification of rock mass weathering using spectral imaging adds to the growing value of remote scanning methods in obtaining geotechnical data rapidly and safely, from often inaccessible locations. Such scanning techniques were used to great benefit in the risk-based paper. The fourth paper analyses zonal failure around deep excavations and the influence of layered jointing. Interestingly, three of the papers in the issue are associated with layering or anisotropy.

The paper describing the design and evaluation of drawbell excavation at the famous Chuquicamata Mine may also be regarded as having risk connotations. The stability of drawbells, and their life, are extremely important to efficient production in a block caving environment. Instability could be a risk to the mining process: disruption of the draw profile, repair requirements, disruption of scheduling, and consequently, loss of production with associated costs. The paper is therefore important in providing guidance on the optimisation of drawbell excavation, the minimisation of blast damage, and hence the creation of value.

Finally, there is a paper illustrating some beneficial technologies that can be learnt from nature, in this case spiders. No doubt there are many other aspects and concepts, already well-developed in nature, that could be directly transferable to our mining technologies, and we should be on the lookout for such information.

In summary, this issue of the Journal provides considerable value. The huge economic value resulting from the research described in the risk-based paper leads me to recommend that the use of a strategic, valuebased decision making criterion would be most appropriate for mining company executives - they should demand, from their managers and operational staff, quantified answers (not opinion-based answers), to the following question: ‘What are the quantified values that will be created in the short-, medium- and longterm due to the implementation of ……… (e.g. new development; new mining method; new mining layout; further exploration drilling; mechanisation; increased or improved rock support; more detailed site investigation, etc; in fact, any proposal or change that could significantly affect safety, production, cost, etc)?’ Such a criterion would result in value-based decisions rather than cost-based decisions. The latter may result in short term benefits, but often cause value destruction in the longer term.

T.R. Stacey

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