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Contents

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PAPERS OF GENERAL INTEREST MSAHP: An approach to mining method selection K. Balt and R.L. Goosen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 451 Mining study selection is the most fundamental activity of a mining study as crucial decision must invariably be made at the study phases when the least information is available. Method selection with AHP (MSAHP) was designed to facilitate good decisions.The program matches the attributes of 10 mining methods to the characteristics of the considered orebody and results in the ranking of the mining methods according to the suitability of each to the orebody in question. The effect of holding time before solidification on the properties of aluminium castings F. Hamed Basuny and M.A. El-Sayed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 461 The effect of holding an Al casting in the liquid state for up to 20 minutes before solidification was studied using a three-level general factorial design of experiments. Two responses were considered, the ultimate tensile strength (UTS) and elongation of the resulting castings. The results showed that the holding treatment had a significant effect on the elongation of the castings produced. In addition, the UTS and elongation peaked at a holding time of 10 minutes.

International Advisory Board R. Dimitrakopoulos, McGill University, Canada D. Dreisinger, University of British Columbia, Canada M. Dworzanowski, Consulting Metallurgical Engineer, France E. Esterhuizen, NIOSH Research Organization, USA H. Mitri, McGill University, Canada M.J. Nicol, Murdoch University, Australia E. Topal, Curtin University, Australia D. Vogt, University of Exeter, United Kingdom

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PAPERS OF GENERAL INTEREST (continued)

Application of a content management system for developing equipment safety training courses in surface mining L. Zujovic, V. Kecojevic, and D. Bogunovic. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 467 Web-based training (WBT) has become a widely popular training option. This study aims to use the Content Management System (CMS) WordPress to develop a web-based application to support traditional training in the mining industry. The study focuses on introducing operators with heavy machinery through pre-shift machine inspections in surface mine operations. This research project implements several plugins to create the application of a training course and an example of a developed course. Such training applications can be used on the Internet and/or through a local area network. An exploration of women’s workplace experiences in the South African mining industry S. Mangaroo-Pillay and D. Botha. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 475 After the inception of the MPRDA in 2002, women’s representation in the South African mining industry increased from 3% to 15% in 2018. Research conducted on women employed in South African mines revealed that the employment of women remains a challenge and that women still face barriers to some extent. This research explored women’s current workplace experiences in the South African mining industry. The study offers practical recommendations that can be implemented by mining organizations to improve women’s workplace experiences in order to encourage and foster transformation in the mining industry. Benhaus – a landmark decision, one less hoop for contract miners but a clarion call for an overhaul of the South African mining regime K. Thambi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 484 Contract mining involves contractual relationships between mine owners or mineral right holders and third parties who conduct mining activities on behalf of the mineral right holders. The current mining income tax legislation has been a grave inhibitor to contract miners. This paper looks at how contract mining has traversed the mining tax landscape, the implications of the Benhaus judgment, and stresses the necessity for clear policy reform to the mining tax regime, in equal measure to legislation framed to give effect to these policies.

The Journal of the Southern African Institute of Mining and Metallurgy

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ment

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s 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

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President’s

The last article

Corner

ndeed, this is my last President Corner’s article as I prepare to hand over the baton to my successor and incoming President of the SAIMM, Mr Vaughn Duke. Twelve months has passed since I assumed the role – how quickly time has gone by. However, it is pleasing to point to a few meaningful activities during my tenure, viz., ➤ The progress with the strategy development for the SAIMM under the leadership of Alastair Macfarlane ➤ The progress with managing our finances to reduce costs and chart our way to a positive balance, led by Vaughn Duke ➤ The prompt response to the impact of COVID-19 and hosting events online to continue our objective of delivering quality and professional knowledge to our members. The leadership of Isabel Geldenhuys and the TPC has ensured that the SAIMM continues to demonstrate its relevance and value-add to members

➤ Establishing a practice of continued learning and knowledge sharing among the Council members through presentations from industry and subject matter experts ➤ The response and adaptation to an ‘unavoidable digital environment’ by the SAIMM office staff as we were all forced to work from home. As I write this last article, the situation has not changed and is likely to prevail for a while longer ➤ Establishing a link with the Minerals Council South Africa, which has the potential to strengthen over time and as the industry evolves in its growth. Looking ahead, I’ll continue to serve the SAIMM as a Past President, carrying on with the key workstream of Professional Development as delegated to me from the strategy development process. My commitment to and passion for the Institute (and the industry) has not waned since joining in 1992 as a fourth-year mining student at Wits. The Institute holds a privileged and unique role in the mining, minerals, and metals industry. As this industry plans for a resurgence and growth to contribute to the country’s economic development, we must all lend a hand to the strength of the Institute. In this regard, transformation is a critical area of focus for this strength building, recognizing and acknowledging the changed South African and industry context, especially in terms of people demographics. Transformation is not an organic process, but one that requires deliberate effort and resolve based on human development and progress for our country’s society – transformation has to remain top of mind and the Council’s agenda for the current and future leadership of the Institute. M.I. Mthenjane President, SAIMM

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MSAHP: An approach to mining method selection K. Balt1 and R.L. Goosen1

Affiliation: 1 Worley, South Africa. Correspondence to: K. Balt Email: kbalt@mweb.co.za Dates: Received: 18 Dec. 2019 Revised: 30 Jul. 2020 Accepted: 30 Jul. 2020 Published: August 2020 How to cite: Balt, K. and Goosen, R.L. MSAHP: An approcah to mining method selection. The Southern African Institute of Mining and Metallurgy DOI ID: http://dx.doi.org/10.17159/24119717/1072/2020

Synopsis Mining method selection is the most fundamental activity of a mining study, because everything else depends on it. It is a process whereby the mining method attributes are matched to the orebody characteristics. This crucial decision must invariably be made at a stage of the study when the least information is available. Method selection with Analytic Hierarchy Process (MSAHP) is based on the Analytic Hierarchy Process (AHP) and was developed in Microsoft Excel™. It was designed to facilitate good decisions based on expert judgement and sparse data according to a systematic mathematical process. The program matches the attributes of 10 mining methods to the characteristics of the orebody under review and results in the ranking of the mining methods according to their suitability to the orebody. The underlying premise of MSAHP is that the mining method best suited to the orebody will also be the most economical.

Keywords mining method selection, orebody characteristics, Analytic Hierarchy Process.

Introduction Mining method selection is a process whereby the mining method attributes are matched to the orebody characteristics. The mining method whose attributes most closely match the orebody characteristics is the one with the highest potential for successful extraction and, by implication, should result in the best business case. This tool, developed in Microsoft Excel™ and based on the Analytic Hierarchy Process (AHP), is named Method Selection with AHP (MSAHP). The tool prompts the user for both numeric and linguistic descriptions of the orebody characteristics based on the information available at the time of the analysis. During the process, the descriptions are quantified according to assigned discreet values. In parallel, the mining method attributes are compared to each other, pairwise fashion, with respect to each orebody characteristic, and the relative suitability of the mining method attributes to the orebody is quantified through AHP. Finally, the two parts of the analysis are synthesized, and this results in the ranking of the mining methods according to the suitability of each to the orebody in question.

Objective The objective of this work was to simplify the mining method selection process, while at the same time modernizing the technology, to facilitate quick decisions, based on minimal information, in the early phases of mining studies.

Scope The underlying premise of MSAHP is that the mining method best suited to the orebody will also be the most economical. It is stressed that MSAHP is not a substitute for any economic model. Its primary use is to identify mining methods with attributes that most closely match the orebody characteristics and, consequently, to inform the mining engineer on the mining methods that need to be focused on for subsequent study phases and more robust technical, economic, and financial models tuned to those mining methods. MSAHP is primarily intended for application to underground, hard-rock mining methods; however, open-pit mining is included because of its versatility and its widespread application to shallow orebodies. The Journal of the Southern African Institute of Mining and Metallurgy

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MSAHP: An approach to mining method selection Mining methods specific to underground soft rock, such as coal and salt, were not considered per se, but the principles are the same. It should be noted that longwall stoping in this work refers to long (about 30 m), narrow, and normally flat-dipping panels in hard rock; and not to the widespread longwall mining method as understood in the context of coal mining. Mining methods which have become largely redundant, like shrinkage stoping and top slicing, have been excluded from consideration because they are now rarely applied. Controllable factors, such as mining factors and mining costs, are included in MSAHP to facilitate the selection if the technical ranking is very close. MSAHP is intended to facilitate the mining method selection process and not to select the mining method. This is the task of the skilful and experienced mining engineers who will use MSAHP to verify and justify their selection rather than to make the selection.

Importance of mining method selection Mining method selection is the most fundamental activity in a mining study because everything else depends on it. The mine design and scheduling cannot be established before the mining methods are decided upon. Equally, if the choice of mining methods changes after mine design and scheduling have commenced, significant and costly delays and overruns on the project plan and schedule are inevitable. This crucial decision must invariably be made at a stage of the study phases when the least information is available. The MSAHP was designed to facilitate good decisions based on expert judgement according to a transparent process, to complement quantified parameters.

History of mining method selection The problem of selecting the appropriate mining method has been grappled with for decades. The first pioneer to devise a numerical approach was David E. Nicholas in the early 1980s (Nicholas, 1981). Nicholas’ approach has been used ever since, with some modification by the University of British Columbia who devised an online tool that allows for interactive input and feedback. Statistics on how often these tools have been used have not been researched. Nicholas approached the selection process in two stages. In Stage 1, those mining methods which should be considered in greater detail are identified based on the orebody geometry, grade distribution, and geomechanical properties of the orebody and host rock. In Stage 2, costs, production rate, labour, and other mining factors are selected from among the mining methods identified in Stage 1. Nicholas’ method is fairly robust and appears to have been widely applied in the industry. However, it does have shortcomings, some of which are highlighted below.

Resolution The parameter ranges in this scheme are coarse. For example, an orebody thickness of 10 m or less is deemed narrow; however, a mining method suitable for a 1.5 m thick, flat-dipping orebody is different from one that is suitable for 9 m thickness. Equally, the range for intermediate dip is 20° to 55°, but a mining method suitable for 25° dip is different from one that would be considered for a 43° dip.

Bias In the Nicholas method the emphasis automatically placed on the geomechanical properties of the rock mass introduces unnecessary bias because the rock mechanics parameters for the hangingwall, ore, and footwall are summed. Thus, the geomechanical properties are assigned a weight three times that of any of the other parameters, making this the single most important selection criterion. In practice the rock mechanics considerations guide the layout and design of the chosen mining method, but they seldomly decide the mining method.

Insufficient differentiation In the Nicholas method, all the parameters considered carry the same weight, regardless of the relative importance of the individual parameters. For example, two mining methods might be suitable to a thin orebody; however, one might be more suitable to a steep dip and the other to a flat dip. Nicholas’ method does not allow for this type of prioritization.

Concise introduction to AHP In the early 1980s, Thomas L Saaty introduced the AHP. The following, most concise definition of the AHP, is given by Saaty: ‘The Analytic Hierarchy Process (AHP) is a theory of measurement through pairwise comparisons and relies on the judgements of experts to derive priority scales. It is these scales that measure intangibles in relative terms. The comparisons are made using a scale of absolute judgements that represents, how much more, one element dominates another with respect to a given attribute. The judgements may be inconsistent, and how to measure inconsistency and improve the judgements, when possible to obtain better consistency is a concern of the AHP. The derived priority scales are synthesised by multiplying them by the priority of their parent nodes and adding for all such nodes’ (Saaty, 2008, p. 83) This definition is illustrated in Figure 1.

Sum

Alternatives Principle of Identity and Decomposition

Principle of Synthesis

In modern day mining the general shape of the orebody seems to be referred to as either massive or stratiform, and the notion of an irregular orebody seems to be rarely used. The definition of the equidimensional shape fits the modern-day nomenclature of ‘massive’, while ‘stratiform’ is equivalent to ‘platy’ and ‘tabular’ refers specifically to near-horizontal stratiform orebodies. Some of the mining methods that were used widely in Nicholas’ time, such as shrinkage-stoping and top-slicing, British spelling are now seldomly practiced commercially. AUGUST 2020

Criteria

Product

Dated mining methods

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Priority vectors

Hierarchy Principle of Descrimination and Comparative Judgement Matrix

Consistency Pairwise comparison

Figure 1—The AHP wheel after Balt (2016) The Journal of the Southern African Institute of Mining and Metallurgy

MSAHP: An approach to mining method selection For MSAHP, the actual orebody characteristics are assigned weights based on linguistic descriptions such as ’very deep’, ‘steeply inclined’, ‘poor’, ‘uniform’ etc., but also, where appropriate, actual values. In parallel, the mining method attributes are compared to each other in pairwise fashion with respect to each characteristic. Finally, a vector is determined that ranks the mining methods in order of suitability to the orebody.

Literature review Many papers have been published that deal with the application of AHP to mining engineering problems in general, and specifically to the aspect of selecting the most suitable mining method. Ataei et al. (2008) conducted a survey among 17 experts that were involved in the mine planning and design process. They identified 13 criteria and assessed their relative importance through pairwise comparisons with respect to each evaluated mining method to determine priority vectors. The six considered mining methods were ranked in order of suitability to the characteristics of an orebody in Northern Iran. Their conclusion was that cut-and-fill was the most appropriate mining method for that mine. The most important selection criteria were the orebody thickness, rock mechanics factors, and dip of the orebody. Musingwini and Minnitt (2008) used AHP to rank several mining methods as practised in the platinum fields of the Bushveld Complex in South Africa in order of efficiency. Efficiency criteria were identified, and by drawing on the knowledge and experience of mine technical services and project management practitioners in the industry, the relative importance of each criterion was determined. They found that conventional mining (longwall mining with pillars on dip or strike and scraper cleaning) was the most efficient. Important conclusions that were

drawn include identification of the use of AHP in optimization, production performance, and personnel career path development. Balt (2016) identified a need in the mining industry for a practical guideline to help engineers carry out AHP in any discipline where a choice must be made between multiple alternatives. based on multiple selection criteria. Kluge and Malan (2011) investigated the application of AHP to mining engineering problems, and Yavuz, Iphar, and Once (2008) used AHP to determine the optimum support for a haul road in a colliery. The above review demonstrates that the AHP is an acceptable decision-making tool for mining applications. During the early phases of feasibility studies, simplicity with a degree of uncertainty is better than complexity, which necessarily increases uncertainty in the face of sparse data.

Mining methods Nicholas (1981) rightly observed that: ‘… no one mining method is so restrictive that it can be used for only one set of characteristics…’ . In most analyses the geometry of the orebody necessitates more than one mining method, or hybrid methods that combine the attributes of compatible mining methods. Many variations, combinations, and hybrid systems are employed, and widely varying naming conventions exist. However, only a few basic mining methods are actively employed in the world today. For MSAHP, 10 of these are considered. They are listed in Table I together with concise definitions of each.

Orebody characteristics The essential orebody characteristics for mining method selection were condensed from various sources, including Hustrulid and Bullock (2001), Brady and Brown (2006), Nicholas (1981), and other publications and papers available on the topic.

Table I

Definitions of mining methods as applied to the selection tool Method

Abbreviation

Open pit

OPM

Definition A surface mining method for shallow, flat-dipping orebodies that progresses deeper by mechanical means.

Block cave

BCM

An underground mining method for flat-dipping, thick orebodies that progresses upwards by means of self-sustaining cave propagation of the ore.

Sublevel caving

SLC

An underground mining method for steep-dipping orebodies. The method progresses downwards by means of blasting ore and selfsustaining cave propagation of the host rock. For this work, SLC is assumed suited to steep, relatively narrow orebodies with the hangingwall significantly less competent than the ore. However, it is acknowledged that this is not necessarily so; considering that it is one of the more flexible and versatile mining methods that can be employed successfully to thick, flat-dipping orebodies

Vertical crater retreat

VCR

An underground mining method for steep-dipping orebodies. The method retreats upwards by means of charging holes from a top access and blasting slices off the bottom of the ore into a bottom access.

Transverse open stoping

TOS

An underground mining method for wide orebodies. The mining retreats from the hangingwall side to the footwall side of the orebody through long blastholes drilled from a series of parallel crosscuts in the orebody.

Longitudinal open stoping

LOS

An underground mining method for steep-dipping, narrow orebodies in which mining retreats from the ends of defined blocks of ore through long blastholes drilled from on-reef strike-parallel drifts.

Cut and fill

C&F

An underground mining method that typically progresses upward from the bottom through a series of relatively narrow horizontal cuts that are backfilled to form platforms for the next cut directly above.

Drift and fill Mining

D&F

An underground mining method for flat-dipping, narrow orebodies that progresses through a series of drifts, each of which is backfilled before the next adjacent drift is mined.

Longwall stoping

An underground mining method for flat-dipping, narrow orebodies, in which typically long breast, updip or downdip panels are advanced. Broken ore is recovered by mechanical means (scrapers or low-profile mechanized equipment).

Room and pillar

R&P

An underground mining method for flat-dipping, narrow orebodies that are mined through series of parallel drifts in grid fashion, leaving regularly sized and spaced permanent ore pillars in situ R&P mining in wide orebodies, where the pillar strength is augmented by paste fill, is not considered an independent mining method, but rather a combination of two mining methods, i.e. C&F and R&P. As such it is not considered in this work as a mining method.

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Figure 2—Orebody characteristics and considerations

The experience of mining engineers who had faced the task of mining method selection, including that of the authors, was utilized in judging the suitability of mining methods to these characteristics. All this information had been assimilated during practical applications and it culminated in the MSAHP technique. The orebody characteristics and considerations for MSAHP are shown in Figure 2.

In MSAHP, the distinction between a massive and stratiform orebody is made on the basis of Equation [1]: [1] where RD is the ratio of the area of the footprint to the thickness of the orebody; Ds is the strike dimension of the orebody; Dd is the dip dimension of the orebody; and Th is the orebody thickness. The orebody is suitable for massive mining operations if RD in Equation [1] is true, otherwise it lends itself to stratiform mining methods. For MSAHP the initial value for the constant K is 3. In MSAHP the orebody characteristics are input in both numeric and linguistic terms. Each term is quantified by assigning a value, or weight, to it. The weight of any given term is different depending on whether the orebody is massive or stratiform. For example, short dip and strike dimensions might be advantageous for block caving, while for the same dimensions, longwall stoping would be inappropriate.

Orebody shape and size Massive and stratiform ore deposits For MSAHP, two categories of mining methods have been identified based on the overall shape of the orebody. These are massive and stratiform mining methods. Massive methods are those best suited to orebodies of which the strike length, dip length and thickness are comparable in size, or ‘equidimensional’. Stratiform mining methods are those suited to orebodies of which one dimension is a fraction of the other two. Stratiform examples include the tabular orebodies of the typical South African hard-rock mines and near-vertical vein deposits in many parts of the world, including Kapan in Armenia, Goldboro Mine in Canada, and Canterfield in Australia.

Table II

Quantification of orebody shape and size Orebody general shape Strike dimension

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Dip diamension Weight

Weight

Thickness Weight

Description

Massive

Stratiform

Massive

Stratiform

Massive

Stratiform

0.1

Very short

Very thin

100

0.5

Short

100

Thin

Medium

100

Medium

Long

100

Thick

100

Very long

100

500

Very thick

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Description

The Journal of the Southern African Institute of Mining and Metallurgy

MSAHP: An approach to mining method selection Table III

Quantification of orebody dip and depth Orebody geometry Dip angle

Depth Weight

Degrees

Description

Massive

Stratiform

<15

Flat

100

15 to 30

Slightly inclined

30 to 45 45 to 60 60 to 90

Weight

Description

Massive

Stratiform

100

Very shallow

100

250

Shallow

100

Moderately inclined

750

Intermediate

100

Steeply inclined

100

2 000

Deep

100

Very steeply inclined

100

3 000

Very deep

The numerical values assigned to the terms are empirical and somewhat arbitrary; however, they should be regarded as benchmarks and unless there is substantial reason to believe that they are incorrect, changing them is inadvisable. The quantification for orebody shape and size is shown in Table II.

Orebody geometry

grade characteristics and their quantifications are provided in Table V, and those for geological disturbance in Table VI.

Mining considerations Two additional categories of characteristics were included to enhance the analyses and extend the functionality of the system. The fifth category encompasses the mining factors that are

The angle of dip and the depth of the orebody define the orebody geometry in MSAHP. The quantifications of descriptions for dip and depth are shown in Table III. Quantification is dependent on the shape of the orebody, whether massive or stratiform.

Table IV

Rock mass quality

RMR

Description

Very poor

Poor

Fair

Good

100

Very good

Unlike all the other characteristics, which pertain to the orebody only, geomechanical characteristics include the hangingwall and the footwall. In Nicholas’ method the values assigned to geomechanical characteristics for the ore are added to those of the hangingwall and footwall. This results in over-emphasis of the geomechanical properties at the cost of other very (perhaps more) important parameters such as dip and thickness. In MSAHP, the importance of the geomechanical properties for the ore, hangingwall, and footwall are evaluated independently with respect to each other as well as to the other parameters, by way of pairwise comparisons. In the early phases of studies, most geomechanical engineers will insist on classifying the rock mass quality according to at least one rock mass classification system. The rock mass rating (RMR) system (Bieniawski, 1989) encapsulates the geomechanical properties of rock masses. It is convenient to use the quantification ranges of that system directly, for three reasons:

➤ It is an authoritative system that is very widely used throughout the mining industry ➤ It already quantifies the linguistic terms such as ‘Very good’, ‘Poor’ etc. ➤ It results in a universal understanding of the rock mass quality across disciplines and departments. The quantifications used in MSAHP are listed in Table IV.

Grade characteristics and geological disturbance The distribution and value of grade and the extent of geological disturbance influence the requirements for selectivity and flexibility of mining methods. The terms used to describe the The Journal of the Southern African Institute of Mining and Metallurgy

Quantification of rock mass characteristics Rock mass characteristics

Table V

Quantification of grade characteristics Grade characteristics Distribution

Description

Weight

Highly disseminated

Very low

Disseminated

Low

Moderately uniform

Average

Uniform

High

Highly uniform

Very high

Table VI

Quantification of geological disturbance Geological disturbance %

Description

Weight

Very low

100

Low

Medium

High

Very high

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MSAHP: An approach to mining method selection usually considered for a study, and the final category brings the direct mining cost per ton of ore produced into consideration. These factors are consequential to the choice of mining method and are not selection criteria, but benchmark values for them can be useful to discriminate between mining methods when it is difficult to do so based on the orebody characteristics alone.

Extraction index This is a measure of the ratio of the ore allowed to be broken to the total available ore in reserve. The sterilized ore serves as stability pillars. The terms used to describe the extraction index and their quantifications are presented in Table VII.

Mineable height index The mineable height is the vertical height of a production stope or block of economically mineable ore. It may be restricted because of grade considerations, geomechanical constraints, or practical mining considerations, such as the maximum reach to which equipment can be extended. The terms used to describe the mineable height index and its quantifications are presented in Table VIII.

Overbreak dilution index The overbreak dilution index measures the lowering of the grade of the broken ore because of the introduction of sub-economic material. The terms used to describe the overbreak dilution index and their quantifications are presented in Table IX.

Operational mining losses index This index is a measure of the broken ore that is left underground and is irrecoverable due to geometric, logistical, or other operational-related mining constraints. Table VII

Quantification of extraction index Extraction index %

Description

Weight Massive

Stratiform

50%

Very low

60%

Low

75%

Average

80%

High

100%

Very high

100

Quantification of overbreak dilution index Overbreak dilution index 1%

Very low

100

Low

Med

15%

High

20%

Very high

Table X

Quantification of operational mining losses index Operational mining losses index %

Description

Weight

Very low

100

Low

Med

High

Very high

The terms used to describe the operational mining losses index and their quantifications are presented in Table X.

Production cost per ton mined A final consideration is the cost of mining at steady state. For the MSAHP tool, the direct cost per ton mined was considered to be the best differentiator between mining methods when financial implications are taken into account. Capital and processing costs are influenced by factors other than the mining method and are not directly comparable between one mining method and another, or even the same mining method among different mines. The mining costs are semi-hard-coded into MSAHP. This factor can be easily adjusted at any time to reflect the most up-todate knowledge.

AHP criteria MSAHP deviates from conventional AHP analyses concerned with mining method selection. In the reviewed studies, the mining methods are assessed in pairwise comparison with respect to the criteria. The mining methods would typically be compared to each other with reference to, for example, orebody thickness, and the following questions would be asked:

Table VIII

Quantification of mineable height index Mineable height index m

Description Massive

Stratiform

Very low

100

Low

Med

High

100

Very high

100

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Table IX

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➤ Is cut and fill mining more or less suitable to orebody thickness than drift and fill mining? ➤ How much more or less suitable is it? The difficulty presented by this type of question is that the reference point is not fixed: one mining method might be more suitable to a thick portion of the orebody while another may be more suitable to a thin portion. Instead of this scheme, MSAHP compares orebody characteristics to each other with reference to each mining method. The questions that may be asked in this scheme are as follows: ➤ With reference to cut and fill, is a thick orebody more or less advantageous than a long strike dimension? ➤ How much more advantageous is it? The Journal of the Southern African Institute of Mining and Metallurgy

MSAHP: An approach to mining method selection Table XI

Mining method selection criteria Category

Abbreviation

Item

Orebody dimension

LSD

Long strike distance

LDD

Long dip distance

THCK

Thick orebody

SOB

Steep orebody

DOB

Deep orebody

GQH

Good quality hangingwall

GQO

Good quality ore

GQF

Good quality footwall

Uniform grade

HIG

High grade

GEO

Geologically undisturbed

HEX

High extraction

HMH

High mining height

LDIL

Low overbreak dilution

LML

Low mining losses

Orebody geometry Rock mass quality

Grade and geology

Mining factors

This approach greatly simplifies the cognitive processes while carrying out the pairwise comparisons.

OPM than both LSD and LDD. This is signified by the fraction 1/5 in (LSD, THCK) and (LDD, THCK). In AHP, the convention is to compare the item in the leftmost column relative to the item in the topmost row. If LSD were to be judged five times more important than THCK, the value in (LSD, THCK) would have been 5. As another example, consider SLC. For this mining method LDD is judged three times more important than LDD and the latter is, in turn, three times more important than THCK. The priorities in the column PV gives an indication of the weight of each of the items with respect to the mining method. For both OPM (71%) as well as BCM (78%), the thickness is of much greater significance than the other two dimensions, while for SLC, LSD (59%) is significantly more important than the other two dimensions and LDD (29%) weighs more than double THCK (14%). Calculation of these priorities is beyond the subject matter covered in this paper. For detailed explanations, the reader is referred to Balt (2016).

MSAHP methodology MSAHP consists of two streams of workflow as illustrated in Figure 4. The first stream is concerned with the actual orebody characteristics which are inputs to the analysis by the engineers concerned with the study, based on the available knowledge. The second deals with the ideal attributes for all the mining methods and has been derived from case studies, expert opinions, and the literature. The two streams come together in the synthesis phase,

In MSAHP, the criteria are grouped into categories and pairwise comparisons are made between criteria that are logically related. This obviates the need for comparing seemingly incomparable items; for example, the dip of the orebody and the grade of the ore. The mining method selection criteria used for the pairwise comparisons are given in Table XI.

Pairwise comparison The comparison matrices were populated with judgements based on case studies, the expert opinion of mining engineers who have considerable experience in mining method selection, and published literature, most notably Hustrulid and Bullock (2001) and Brady and Brown (2006). To explain the pairwise comparison process, sets of comparison matrices for three mining methods are shown in Figure 3: open pit mining (OPM), block cave mining (BCM), and sublevel caving (SLC). The matrices compare, in pairwise fashion, the orebody dimensions: long strike distance (LSD), long dip distance (LDD), and thick orebody (THCK). The left-hand matrix of each set is the comparison matrix and the one on the right is the priority matrix in which the relative priorities of the items are calculated. Balt (2016) deals comprehensively with the AHP methodology and the application of ExcelTM to the process. It should be noted at this point that the criteria are specific; for example, ‘long strike distance’ and ‘steep orebody’. The reason for this is to introduce relatively fixed concepts in respect of which the mining methods can be compared. For example, comparing LOS and LWS with respect to dip without qualification leads to a question like: ‘Is LOS more or less suited to the dip than LWS?’, which cannot be answered. By qualifying dip as ‘steep’, the question becomes: ‘Is LOS more or less suited to a steep dip than LWS?’, which has a definitive answer. Since OPM, LSD, and LDD are deemed equally important, the number 1 appears in the row/column intersections. THCK is judged to be five times more important for the consideration of The Journal of the Southern African Institute of Mining and Metallurgy

Figure 3—Snip of pairwise comparison tables showing the matrices of orebody dimensions for three mining methods

Describe orebody characteristics in linguistic terms Quantify descriptions

Determine criteria

Numerical expression of actual orebody characteristics

Pairwise comparison of criteria with respect to each mining method

M A T C H

Numerical expression of ‘ideal’orebody characteristics for each mining method

Mining methods ranked in order of suitability to the orebody

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MSAHP: An approach to mining method selection where the actual orebody characteristics are matched to the ideal attributes for each mining method. The mining methods are then ranked according to the best fit of the orebody characteristics to the ideal attributes for each mining method.

Orebody characterization The orebody characteristics considered for MSAHP were given in Figure 2. The characteristics are grouped into four logical categories: namely the orebody dimensions, the orebody geometry, the rock mass ratings of the hangingwall, ore, and footwall, and the grade characteristics. These are the characteristics that are provided by nature and are not under human control.

Mining factors and production costs The mining factors –extraction, mining height, overbreak dilution, and mining losses – are under the control of the mining engineer, subject to constraints imposed by the mining method. As such, these factors are not selection criteria per se and are used in MSAHP mainly to test the robustness of the mining method ranking order in the face of varying constraining scenarios. When the suitability of mining methods is so evenly matched that a clear decision is not forthcoming, the production cost per ton mined can often be the deciding factor. For this reason, as well as to estimate the effect of production cost on the ranking of mining methods, production cost per ton mined was included as a criterion.

Figure 5—Scores for actual orebody characteristics derived from available information

Synthesis The process is synthesised by finding the product of the priority vector for each criterion with respect to every mining method and the score obtained through the evaluation of the actual orebody characteristics. The final score for each mining method is achieved by summing the products. Figure 5 is an impression of a typical scenario where the given orebody characteristics have been entered and quantified into a score. The score for each of the orebody characteristics is multiplied by the priority vector for each of the criteria shown in Figure 6. This represents the ideal orebody for each mining method. The results of this multiplication are shown in Figure 7. By way of illustration, consider the dip angle. In the evaluation of the actual orebody characteristics, a dip of 35° is described as ‘moderately inclined’ and it results in a score of 50. In Figure 6, the priority of dip for TOS is 83%. The product of these two values is 42, the highlighted value in Figure 7. The values for the criteria are finally summed to produce a total measure of the suitability of each mining method to the actual orebody configuration, and the mining methods are then ranked according to the scores from high to low, as shown in Figure 8. When the analysis reaches this stage, the objectives of the analysis have been achieved. However, it is at this juncture that different scenarios can be evaluated by varying the numbers of the ‘controllable’ variables – that is, the mining factors and the cost. For example: ‘… what if a low dilution index is a requirement, would the ranking change?’

Figure 6—Priority vectors for criteria with respect to mining methods

Benefit to cost ratio Benefit-to-cost ratio has been built into MSAHP to make the analysis more complete. This does not allow MSAHP to be used as a substitute for appropriate economic modelling, but merely

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Figure 7—Synthesised evaluation The Journal of the Southern African Institute of Mining and Metallurgy

MSAHP: An approach to mining method selection Disqualification of mining methods

Figure 8—Final scores and rankings of mining methods in order of their suitability to the actual orebody characteristics

allows for an indication of the effect that costs might have on the selection. This is done by way of determining the benefit/cost ratio. The orebody characteristics are taken as the benefit and the mining and cost per ton considerations constitute the cost. The mining cost per ton is built into MSAHP as a set of userconfigurable variables. A graph like that in Figure 9 is produced. Note that for this analysis, the ranking order has changed, with SLC and C&F swapping places. The mining cost considered for this example is given in Table XII.

All mining methods are constrained by some or other aspect of the orebody geometry. For example, open pit mining at depths greater than about 600 m is very rare and will be considered only under extraordinary circumstances. A feature of MSAHP is that it allows disqualification of mining methods after the ranking order has been established. With the feature disabled, all the mining methods are shown (see Figure 8); when it is enabled only the qualifying suitable mining methods are presented for consideration, as shown in Figure 10, which is based on the same data as Figure 8. Since the final scores for the disqualified mining methods are simply set to zero, the ranking order of the qualifying mining methods is maintained.

Table XII

Mining cost per ton mined Mining cost (US$/t)

OPM

BCM

SLC

VCR

TOS

LOS

C&F

D&F

R&P

Table XIII

Mining method disqualifying criteria Disqualifications

Criterion

Justification

Maximum thickness for narrow tabular mining (NTM) (m)

The use of extra-low-profile equipment has not quite been established on commercial scales. The bulk of this type of orebody is still mined using conventional face drilling and blasting methods. NTM stope widths greater than 6 m pose significant practical challenges and are generally unsafe.

Minimum thickness for OPM (m)

In MSAHP, the lower limit of thickness for OPM is 50 m.

Minimum thickness for BCM (m)

200

In MSAHP, the lower limit of thickness for BCM is 200 m.

Minimum thickness for D&F (m)

The minimum thickness is dictated by the size and capabilities of the equipment used for mining and the requirements imposed by the fill infrastructure. Currently available and proven equipment cannot function efficiently in stope heights of much less than about 3 m.

Maximum thickness for D&F (m)

The maximum thickness for D&F mining is determined by the length that can be efficiently drilled, the volume of fill that can be transported and placed within a reasonable time, and the requirement of fill to be in contact of the rock walls against the forces of gravity and slumping.

Minimum thickness for C&F and open stoping (m)

Similar to the constraints for mass mining methods, open stoping, and particularly C&F, require considerable amounts of upfront capital. These mining methods are generally not viable for orebodies that are less than 10 m thick.

Maximum depth for OPM (m)\

600

Although there are pits deeper than 600 m, these are exceptional cases. The average maximum depth of open pits is currently less than 600 m.

Maximum dip for tabular mining (degrees)

Much of the development for tabular mining requires trackless equipment. For this a dip of between 8 and 12° is required; however, apparent dip drives can be employed to facilitate mining. For conventional manual stoping of orebodies, dips steeper than 35° are inherently unsafe.

Minimum dip for ’steep’ mining (degrees)

If the dip is less than about 35°, steep mining methods are limited because most of them require a dip greater than the natural angle of repose of the broken ore to take advantage of gravity in the recovery of broken ore after blasting or caving.

Maximum depth for R&P (m)

1 000

As mining progresses deeper, stresses become higher and to maintain the pillar factor of safety, pillars must necessarily become bigger. At some point the required pillar sizes are so large that economical mining is no longer possible.

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MSAHP: An approach to mining method selection The case studies demonstrate that the technique, although by no means claimed to be flawless, is robust enough to give adequate guidance to the mining method selection process. The case studies show that MASHP is a practical and implementable tool for mining method selection, even in the face of sparse data.

Case studies Many case studies were back-analysed. The input information in all cases was sourced from publications and the internet. It is certain that for pre-feasibility and feasibility study phases, considerably more information is normally available; nevertheless, in all the case studies, the mining methods in the source documents were in the top four of the MSAHP-ranked mining methods.

Figure 9—Benefit to cost ratio

References Ataei, M., Jamshidi, M., Sereshki, F., and Jalali, S.M.E. 2008. Mining method selection by AHP approach. Journal of the Southern African Institute of Mining and Metallurgy, vol. 108. pp. 741–749. Balt, K.D. 2016. A methodology for implementingt he analytic hierarchy process to decision making in mining. Worley, Johannesburg. Bieniawski, Z.T. 1989. Engineering Rock Mass Classifications: A Complete Manual for Engineers and Geologists in Mining, Civil, and Petroleum Engineering. 1st edn. Wiley-Interscience, New York. Brady, B.H.G. and Brown, E.T. 2006. Rock Mechanics for Underground Mining, 3rd edn. (reprinted with corrections. Springer, Dordrecht.

Figure 10—Rankings after disqualification Hustrulid, W.A. and Bullock, R.C. (eds). 2001. Underground mining methods: engineering fundamentals and international case studies. Society for Mining,

The disqualifying criteria are shown in Table XIII. One additional disqualification may be imposed by the user: The impact of mining on the environment is a very serious consideration and there are areas where the Earth’s surface may not be disturbed. In these cases, mining methods that have the potential to cause substantial displacement, such as BCM and SLC, must be disqualified even if they are the preferred mining methods.

Kluge, P. and Malan, D.F. 2011. The application of the analytical hierarchical process in complex mining engineering design problems. Journal of the Southern African Institute of Mining and Metallurgy, vol. 111. pp. 847–855. Musingwini, C. and Minnitt, R.C.A. 2008. Ranking the efficiency of selected platinum mining methods using the analytic hierarchy process (AHP). Proceedings of the Third International Platinum Conference: ‘Platinum in Transformation’.

Conclusions

Southern African Institute of Mining and Metallurgy, Johannesburg. pp.

Mining method selection, the most fundamental aspect of mine design, is also inherently one of the most difficult because the selection must take place when information is at a minimum. Several methods and techniques have been developed, and without doubt will continue to be developed to help with the selection process. The AHP is powerful and computationally relatively simple, although it does require considerable time and study to really understand it. Time is almost never an abundant resource, and so designers will always fall back on what is easiest and familiar and will give quick results that are at least approximately correct, unless there is something simpler that they can trust. This paper discussed a transparent, user-friendly technique which simplifies mining method selection even though it is driven by a powerful and proven decision-making process.

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319–326. Nicholas, D.E. 1981. Method selection - A numerical approach. https://www. cnitucson.com/publications/1981_Nicholas_436-Method%20Selection%20-%20 A%20Numerical%20Approach%201981.pdf. Saaty, T.L. 2008. Decision making with the analytic hierarchy process. International Journal of Services Sciences. vol. 1. pp. 83–98. Yavuz, M., Iphar, M., and Once, G. 2008. The optimum support design selection by using AHP method for the main haulage road in WLC Tuncbilek colliery. Tunnelling and Underground Space Technology, vol. 23. pp. 111–119. https:// doi.org/10.1016/j.tust.2007.02.001

The Journal of the Southern African Institute of Mining and Metallurgy

The effect of holding time before solidification on the properties of aluminium castings

F. Hamed Basuny1 and M.A. El-Sayed2 Affiliation: 1 Industry Service Complex, Arab Academy for Science and Technology and Maritime Transport, Abu Qir, Alexandria, Egypt. 2 Department of Industrial and Management Engineering, Arab Academy for Science and Technology and Maritime Transport, Abu Qir, Alexandria, Egypt. Correspondence to: M.A. El-Sayed

Email:

drmahmoudelsayed12@gmail. com

Synopsis The properties of aluminium castings are strongly affected by their inclusion content, particularly double oxide film defects, or bifilms. Such defects have been reported not only to decrease the tensile and fatigue properties of Al casting, but also to increase their variability, making the properties of such alloys unreliable and unreproducible. Earlier research suggested that the bifilm atmosphere might be consumed by reaction with the surrounding melt, which could improve the mechanical properties of the castings. In this work, the effect of holding an Al casting in the liquid state for up to 20 minutes before solidification was studied using a three-level general factorial design of experiments. Two responses were considered, the ultimate tensile strength (UTS) and elongation of the resulting castings. The results showed that the holding treatment had a significant effect on the elongation of the castings produced. In addition, the UTS and elongation peaked at a holding time of 10 minutes. Scanning electron microscopy (SEM) investigation detected many oxide fragments inside pores on the fracture surfaces, reflecting the role of entrained defects in the formation of porosity. The results suggest that two opposing phenomena may take place during the holding treatment. Thus, the consumption of air inside the entrained defects due to reaction with the surrounding molten metal may lead to improvements in mechanical properties, but this may be accompanied by hydrogen passing into the defects, which has a deleterious effect on properties. Keywords oxide film, aluminium casting, porosity, defects, hydrogen, design of experiments.

Dates:

Received: 27 Jan. 2020 Revised: 13 Aug. 2020 Published: August 2020

How to cite:

Hamed Basuny, F. and El-Sayed, M.A. The effect of holding time before solidification on the properties of aluminium castings. The Southern African Institute of Mining and Metallurgy DOI ID: http://dx.doi.org/10.17159/24119717/1102/2020 ORCiD ID: F. Hamed Basuny https://orchid.org/0000-00023342-7524 ORCiD ID: M.A. El-Sayed https://orchid.org/: 0000-00033086-0872

Introduction The mechanical properties of Al castings are greatly affected by their inclusion contents, especially what is called the double oxide film defect or bifilm (Campbell, 1993; Griffiths, Elsayed, and El-Sayed, 2016; El-Sayed, 2016; El-Sayed, Hassanin, and Essa, 2016a; Basuny et al., 2016). This defect is created due to surface turbulence of the liquid Al, which is a common foundry phenomenon during metal handling, transfer and/or pouring. If liquid aluminium enters a mould cavity with a velocity greater than a critical value, the surface oxide film of the liquid metal will fold over onto itself (but not fuse) and be submerged into the bulk liquid with a volume of air entrapped, creating crevice-like pores with an oxidized interior surface (El-Sayed, 2014, 2018a; El-Sayed and Ghazy, 2017). Entrained double oxide film defects represent the easiest possible initiating features for cracks and pores, since they are not in atomic contact with the liquid and their dry inner surfaces can be separated with minimal effort (El-Sayed and Griffiths, 2014, El-Sayed, Hassanin, and Essa, 2016b, El-Sayed, 2018b). Also the strength of these features is much lower than the rest of the matrix and the fracture path is expected to preferentially go through them. In addition, double oxide films are considered to be favourable sites for the initiation of pores (Akhtar et al., 2009) and for the nucleation and growth of a wide variety of intermetallic phases (Cao and Campbell, 2003, Asadian Nozari et al., 2015, Samuel et al., 2017). These defects not only reduce the elongation, tensile strength, and fatigue limit of the aluminiumcasting, but also increase their variability (Khaleghifar, Raiszadeh, and Doostmohammadi, 2015; El-Sayed et al., 2011, 2018; El-Sayed, 2012). Oxide films were also suggested to increase the variability in the fluidity of Al melts during the casting process (Timelli and Caliari, 2017). Nyahumwa, Green, and Campbell (1998) suggested that, due to the transformation of the oxide layer from γ-Al2O3 to α-Al2O3, (a process thought to take about 5 hours), cracks are introduced into the oxide skin which allow the liquid aluminium to come into contact and react with the atmosphere inside the defect (mainly oxygen and nitrogen). This mechanism could result in the consumption of the atmosphere inside the bifilm and possibly lead to its deactivation (Nyahumwa, Green, and Campbell, 1998b).

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The effect of holding time before solidification on the properties of aluminium castings This conjecture was further supported by Griffiths and Raiszadeh (2009), who trapped an air bubble (as a proxy for a bifilm) inside liquid Al and monitored its change in volume with time using real-time X-ray radiography. Their results showed that the oxygen in the trapped air should be consumed first, to form Al2O3, then the nitrogen would react to form AlN. These reactions started immediately, (with no need for an initiating phase transformation). They also reported an increase in the volume of the bubble when the initial hydrogen content of the melt was higher than the hydrogen equilibrium level associated with the ambient atmosphere, which was suggested to be due to hydrogen diffusion into the bubble (Griffiths and Raiszadeh, 2009). Detailed experiments, using a pore gas analyser to investigate the change in the composition of an air bubble trapped in different Al alloys, demonstrated that hydrogen can diffuse through an oxide layer, showing how a double oxide film defect can grow into a hydrogen-filled pore (El-Sayed et al., 2013, 2014; Griffiths, Caden, and El-Sayed; 2014a, 2014b). Design of experiments (DoE) is a systematic method to help the determination of the relationship between factors affecting a process and the output of that process, and is used to find cause-and-effect relationships. This information is needed to manage process inputs in order to optimize the output. A common experimental design is the three-level design, written as a 3k factorial design (Croarkin, Tobias, and Zey, 2002). This means that k factors are considered, each at three levels. These are (usually) referred to as low, intermediate, and high levels. These levels are numerically expressed as 0, 1, and 2. If there are k factors, each at three levels, a full factorial design has 3k runs. The purpose of the current study was to explore how the holding time of the casting in the liquid state before solidification (oxide film age) could affect the amount and morphology of bifilm defects, and by implication the tensile properties of the resulting castings. A general factorial design was used for the modelling of the casting process. The results of this investigation could lead to the development of techniques by which oxide film defects might be reduced or eliminated in aluminum castings.

Experimental

Castings from an 1100 Al alloy were produced by gravity casting. To perform the design of experiments, Design-Expert Software Version 7.0.0 (Stat-Ease Inc., Minneapolis, USA) was used and the general factorial design was adopted to analyse the effect of holding time before solidification on the mechanical properties of the Al casting. The three-level general factorial design was selected because the parameters could be easily varied at three discrete levels and statistically analysed using only three experiments in all, making the DoE easy to regulate and execute due to low complexity. In this work the studied parameter (oxide film age) was varied at ‘0’, ‘1’, and ‘2’ values and its effect on the UTS and elongation was evaluated. Three experiments were undertaken to produce castings from an 1100 Al alloy containing bifilms of different ages: zero, 10, and 20 minutes. Aluminium ingots were supplied by AluTech - Egyptian Germany Co. The chemical composition of the alloy, certified by the supplier, is given in Table I. The accuracy of the measurements was reported to be ≤0.005 wt.%. In each experiment, about 10 kg of the aluminium was melted in an induction furnace. The liquid metal was then prepared in such a way as to promote surface turbulence and splashing, by pouring from a

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Table I

Chemical composition of 1100 Al alloy (wt.%) Si

0.3

0.6

0.15

0.1

Bal.

height of about 1 m into preheated ceramic shell moulds, and stirring in an induction furnace, using a power setting of 7.5 kW and frequency of 2350 Hz, for one minute. This was intended to create and entrain new bifilm defects. In one experiment, the casting was allowed to solidify immediately to preserve any bifilm defects created during the melt stirring or mould filling. In the other two experiments, the metal was maintained in the liquid state by placing the filled ceramic shell mould in a resistance-heated furnace for 10 or 20 minutes, then removing it to allow solidification. After solidification, each of the castings was machined into 20 tensile test bars for determination of their ultimate tensile strength and elongation at failure. The tensile tests were conducted with a WDW-100E universal testing machine using a crosshead velocity of 1 mm.min–1. To evaluate the H content of the castings, a LECO sample was cut out from the solidified castings from each experiment. The samples were machined to the dimensions of standard Leco samples (8 mm diameter and 49 mm length), and analysed to determine the hydrogen content of the castings from the different experiments. Finally, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) studies were carried out on the fracture surfaces of the tensile test specimens using a Philips XL-30 scanning electron microscope with Oxford Inca EDS, for the evidence of any bifilms.

Results

The H content of the solidified castings from these experiments was determined to be 0.22, 0.3, and 0.51 cm3 per 100 g respectively for the castings that contained oxide films aged for zero, 10, and 20 minutes. The error in the hydrogen measurement was shown in an earlier study to be in the range of 0.002 cm3 per 100 g (El-Sayed and Griffiths, 2014). The values of ultimate tensile strength (UTS) and per cent elongation for specimens cut from the solidified castings are presented in Table II. Figure 1 presents a normal probability plot of the residual, and a plot of the residual against experimental run order for the UTS values. A normal probability plot of the residual, and a plot of the residual against run order, for the per cent elongation values are shown in Figures 2a and 2b respectively. The observed points on both normal probability plots were distributed relatively near to the straight line. In addition, the residuals versus the experimental run order plots showed random scatter without any specific trend. This could suggest that the residuals followed a normal distribution and the observations were independently distributed for the two responses evaluated in this study. Figures 1 and 2 show a high outlier (out of the 60 values) for the UTS and elongation (62 MPa and 47 respectively), which is indicated by arrows. This is a typical demonstration of the random nature of the bifilm effect on mechanical properties, as by chance a sample from the casting might be free from bifilms with a corresponding highly improved UTS and/or elongation. In an earlier study (Nyahumwa, Green, and Campbell, 1998a), it was reported that Al castings that were free from bifilm defects exhibited up to 100 times higher fatigue lives. The Journal of the Southern African Institute of Mining and Metallurgy

The effect of holding time before solidification on the properties of aluminium castings Table II

UTS and per cent elongation of tensile specimens from Al castings held for different periods in the liquid state prior to solidification

Sample No.

UTS (MPa) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Average

Zero

Holding time (minutes)

Elongation %

UTS (MPa)

48 54 55 46 50 53 56 49 45 57 51 50 47 53 54 55 52 42 56 56

30 31 33 34 35 27 34 21 30 25 27 39 40 34 32 47 31 28 26 28

51.5 ± 4.2

31.6 ± 5.9

Elongation %

UTS (MPa)

55 54 50 50 56 59 53 55 52 58 54 57 54 53 58 49 53 57 51 48

35 36 39 36 35 30 34 36 31 31 38 33 32 40 39 36 36 36 37 36

49 43 57 56 51 54 62 54 47 46 55 53 56 45 50 52 52 51 48 58

29 22 25 19 23 31 29 23 32 28 27 25 28 29 24 31 31 32 33 30

53.8 ± 3.1

35.4 ± 2.8

52 ± 4.8

27.6 ± 3.9

Figure 1—(a) Normal probability plot of the residuals, and (b) residuals against run order, of UTS

Analysis of UTS Table III shows the analysis of variance results for the UTS values shown in Table II. The ‘Model F-value’ of 1.81 implies that the model is not significant relative to the noise. In other words, there The Journal of the Southern African Institute of Mining and Metallurgy

Elongation %

Figure 2—(a) Normal probability plot of the residuals, and (b) residuals against run order, of elongation per cent

was a 17.23% chance that a ‘Model F-value’ this large could occur due to ‘noise’. Therefore, the results of the model suggested that the age of the oxide films had no significant effect on the UTS of the castings produced. VOLUME 120

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The effect of holding time before solidification on the properties of aluminium castings Table III

A NOVA results, where values of ‘p-value’ less than 0.05 indicate that model terms are extremely significant, and values greater than 0.1 indicate the model terms are not significant Source variation Oxide Film age Error Corresponding Total

Sum of squares

Degrees of freedeom (df)

Mean square

F-value

p-value

2 57 59

30.45 16.79

1.81

0.1723

60.90 956.98 1017.89

Table IV

A NOVA results, where values of p-values less than 0.05 indicate model terms are extremely significant and values greater than 0.1 indicate the model terms are not significant Source of variation Oxide Film age Error Corresponding Total

Sum of squares

Degrees of freedeom (df)

Mean square

F-value

p-value

2 57 59

310.58 19.26

16.13

<0.0001

621.15 1097.54 1718.70

Figure 3 shows the effect of oxide film age on the mean UTS of the test bars cut from different castings (with different holding times before solidification). The average UTS increased from 51.5 ± 4.2 MPa (solidified immediately) to 53.8 ± 3.1 MPa (held in the liquid state for 10 minutes before solidification). However, as the holding period increased to 20 minutes, the mean UTS decreased to 51.9 ± 4.8 MPa. Although this effect was suggested to be statistically insignificant, it might be an indication of a slight improvement in the UTS at a holding time of 10 minutes.

Analysis of elongation Table IV shows the analysis of variance results for the elongation (%) values shown in Table IV. The Model F-value of 16.13 implies that the model was significant. In other words, there was less than 0.01% chance that a Model F-value this large could occur due to ‘noise’. Therefore, the results of the model suggest that the age of the oxide films had a notable on the elongation of the castings produced. Figure 4 shows the effect of oxide film age on the per cent elongation of the test bars cut from different castings (with different holding times before solidification). The age of oxide films showed an effect on the per cent elongation of the Al castings, with a peak at 10 minutes’ holding time. Like the UTS, the mean per cent elongation of the castings maintained at 800°C for 10 minutes prior to cooling was higher than for those solidified immediately or held in the liquid state for 20 minutes before solidification. SEM examination (Figures 5a–f) of the fracture surfaces of different samples from different conditions (holding times), did not detect oxide films lying on the fracture surfaces. Instead they were often detected inside pores. The identity of the alumina film was confirmed by EDX analyses that detected relatively large amounts of oxygen (indicated by the atomic per cent, which ranged from 20 to 32) at the suspected bifilm layers This is a likely indication that the origins of the pores were primarily bifilm defects, which might have changed their morphologies during the holding treatment and/or solidification of the casting to form pores. This would be an indication of the role played by bifilms in initiating porosity in light metal alloy castings. It should be

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Figure 3—Effect of holding time on the UTS of the Al alloy

Figure 4—Effect of holding time on the elongation (%) of the Al alloy

emphasized that the roughness of the fracture surfaces of test bars might affect the accuracy of EDX analysis carried out in this study. The Journal of the Southern African Institute of Mining and Metallurgy

The effect of holding time before solidification on the properties of aluminium castings also shown that the excess hydrogen that was ejected during solidification might diffuse into the bifilm gap, increasing its size to form a pore which affects the properties adversely (El-Sayed et al., 2014). The current results suggest that two opposing mechanisms were taking place simultaneously during the holding of an Al casting in the liquid state prior to solidification and/or the solidification process itself (suggested to take about 4 minutes – El-Sayed and Essa, 2018). i. The first mechanism was related to the reaction between oxygen and nitrogen within the bifilm defect and the contiguous melt, which decreases the bifilm size and in turn improved the mechanical properties. ii. On the other hand, another mechanism occurs which may be related to the amount of hydrogen picked up by the liquid metal from the surrounding atmosphere (which increased as the molten metal was spending more time in the liquid state before being completely solidified). This hydrogen could diffuse into the bifilms and this would lead to degradation of the overall mechanical properties due to increased porosity.

Figure 5—Secondary electron SEM images of pores containing oxide film defects on the fracture surfaces of Al alloy specimens that were held in the liquid state for different periods before solidification, (a) and (b) zero, (c) and (d) 10 minutes, and (e) and (f) 20 minutes

Discussion The modelled graphs of the holding time versus the UTS and elongation (Figures 3 and 4), show that both the mean UTS and mean percentage elongation peaked when the castings were kept in the liquid state for 10 minutes before solidification. The mean values dropped (much more for elongation) when the holding period was increased to 20 minutes. Also, the ANOVA results, presented in Tables III and IV, suggested a significant effect of the holding time on the elongation of the casting produced. Finally, the hydrogen content of the solidified casting was found to increase consistently with the holding time (an increase of about 230% during the 20-minutes holding time). Raiszadeh and Griffiths (2006) and El-Sayed et al. (2013) suggested that the interior atmosphere of a bifilm could be consumed within a few minutes due to reaction with the surrounding liquid Al. This would reduce the size of bifilm defects and hence reduce their deleterious effects on the mechanical properties of the Al castings. In addition, it was The Journal of the Southern African Institute of Mining and Metallurgy

It could be argued that the mean UTS and elongation values of the castings allowed to solidify immediately after pouring represented the tensile properties of castings with bifilms that were beginning to lose their internal atmosphere, but also had the lowest H levels. During the early stages of holding the first mechanism, consumption of air inside the bifilms, was more prevalent, and there was an improvement in the properties, which reached a maximum at 10 minutes’ holding. At this time, bifilm defects may have lost most of their oxygen and nitrogen by reaction with the surrounding liquid Al, while the H content increased by only a small amount. Consequently, the shape of the double oxide films would be expected to be less deleterious to the mechanical properties. However, increasing the holding time to 20 minutes did not cause any further improvement in the mechanical properties as most of the initial atmosphere of bifilms might have already been consumed. On the contrary, the extended holding resulted in a degradation of the properties due to an increasing H content of the melt and hence an increasing H content of the double oxide films and of the porosity size in the final casting. Therefore, it could be suggested that these two opposing mechanisms during the holding treatment may cancel one another over the 20-minute holding period, hence the average values of the UTS of the castings with zero and 20-minutes holding times were almost the same (51.5 ± 4.2 and 51.9 ± 4.8 MPa, respectively). In addition, the second mechanism, related to H diffusion into the bifilm gap, appeared to have a more harmful effect on the elongation, as the average values of the elongation of the Al castings decreased from 31.6 ± 5.9% (solidified immediately) to 27.6 ± 3.9% (held for 20 minutes before solidification). However, taking the errors into account, these values were relatively close. SEM detected numerous alumina films, demonstrated by EDX, where such films, were mostly associated with pores (Figure 5). Griffiths and Raiszadeh (2009) suggested that hydrogen in the Al melt could diffuse into the bifilm, causing its expansion into a pore, which might be subsequently torn apart (due to its extreme thinness), leaving only some oxide fragments inside the pore. Therefore, it could be speculated that these oxide-related VOLUME 120

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The effect of holding time before solidification on the properties of aluminium castings pores may have been formed due to the diffusion of H from the melt into bifilms. This could be in accordance with the current results, which suggested that the diffusion of hydrogen into the bifilms increases the size of the defects and hence detracts from improvements in the mechanical properties of the castings resulting from the consumption of the bifilm atmosphere. Since the results of the current study suggested a relationship between bifilms and porosity in Al castings, it is recommended that a quantitative assessment of the size and volume fraction of pores as a function of the holding time be conducted. This could be achieved by determination of a parameter called the ’Bifilm index’, which is defined as the total length of bifilms estimated on the surface of a reduced pressure test (RPT) sample (Dispinar and Campbell, 2006). This might be helpful in the correlation of holding time of the casting in the liquid state before solidification and the amount and size of bifilms and/or pores on the surface of the casting.

Conclusions 1. SEM examination of the fracture surfaces revealed the presence of oxide films, which demonstrated a role for such defects in influencing the failure of Al castings. 2. The tensile properties of Al castings peaked when they were held in the liquid state for 10 minutes before solidification. This might be attributed to a change in the morphology of their entrained bifilms during the holding treatment, with a corresponding change in their harmful influence on the properties. 3. Holding Al castings in the liquid state for 20 minutes before solidification did not cause any significant change in the UTS, while it reduced the elongation of the castings produced by about 12%.

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Timelli, G. and Caliari, D. 2017. Effect of superheat and oxide inclusions on the fluidity of A356 alloy. Materials Science Forum, vol. 884. pp. 71–80. doi:10.4028/www.scientific.net/MSF.884.71 u The Journal of the Southern African Institute of Mining and Metallurgy

Application of a content management system for developing equipment safety training courses in surface mining L. Zujovic1, V. Kecojevic1, and D. Bogunovic2 Affiliation: 1 Department of Mining Engineering, West Virginia University, Morgantown, WV, USA. 2 North American Coal Corporation, Farmington, NM, USA. Correspondence to: L. Zujovic

Email:

lz0011@mix.wvu.edu

Dates:

Synopsis Web-based training (WBT) has become a widely popular training option that can be applied throughout a variety of areas and industries. Mining is a challenging industry that is continuously searching for improvements in its safety training processes. We used the content management system (CMS) WordPress to develop a web-based application to support traditional training in the mining industry. The study focuses on introducing operators of heavy machinery in surface mining operations to preshift machine inspections. WordPress does not require technical skills, and in addition to its default features, it offers a vast number of useful plugins. This project implements several plugins to create an application with training courses. In this paper we present both the process of creating a training course and an example of a developed course. Such training applications can be used on the internet or through a local area network. Keywords web-based training, WordPress, safety training, surface mining.

Received: 30 May 2020 Revised: 13 Aug. 2020 Accepted: 13 Aug. 2020 Published: August 2020

How to cite:

Zujovic, L., Kecojevic, V., and Bogunovic, D. Application of a content management system for developing equipment safety training courses in surface mining. The Southern African Institute of Mining and Metallurgy DOI ID: http://dx.doi.org/10.17159/24119717/1233/2020 ORCiD ID: L. Zujovic https://orchid.org/0000-00026197-1041

Introduction Sustaining the quality of equipment safety training and education is one of the major responsibilities for any mining company, including both management and workforce. Heavy machinery, such as haul-trucks, dozers, and excavators, is essential for every mine operation and project. In the perennial challenge to secure safe working environments, it is of paramount importance for mining professionals to establish safety training. Additionally, training is mandated by the Mine Safety and Health Administration (MSHA, 30 CFR, Parts 46 and 48). Such training is given not only to miners assigned for duties for which they do not have previous experience (e.g. mobile equipment operators), but also to experienced miners who must undergo routine refresher training. Kral (2002) stated that one of the best ways to retain personnel at mines is by promoting a safe work environment and training them to operate equipment properly. Peters, Vaught, and Mallet (2010) discussed thirty years of NIOSH (National Institute for Occupational Safety and Health) and US Bureau of Mines research on health and safety training in mining and made suggestions for major future improvements in miners’ safety training. Gao et al. (2019) investigated the role of safety management in the development of safety culture. Out of the four safety management practices that they found to have a positive impact on safety culture, one was related to safety training, and another to inspection and monitoring. Brnich et al. (2002) suggested training improvements in the form of short, five-toseven minute videotapes about fire prevention in the context of the miners’ workplace. They concluded that these videos had improved employee awareness about hazards and that such modules can be expanded to other topics. Researchers have discussed different approaches to training and education in mining processes. Akkoyun and Careddu (2013) developed a computer program for teaching and learning in mining engineering-related courses. The authors selected an open pit magnesite mine to create a simulation application, concluding that such computer applications can be used for lectures in surface mining, drilling, blasting, mining economy, etc. Zhang and Kecojevic (2016) investigated both fundamental and traditional approaches as well as innovative and creative ones to mitigate the causes of incidents at mining sites. These authors also suggested improvements to training and education systems. Despite being a relatively new technology, web-based training (WBT) and internet education are now widely used and supported. Many platforms such as Udemy and Coursera offer a wide range of courses in computer science, business, leadership, and many other disciplines. At the beginning of

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Application of a content management system for developing equipment safety training courses this century, Fahy (2004) addressed the potential uses of WBT, suggesting that such delivery models would continue to grow as technologies become more available. He concludes that the potential strength of WBT might improve many kinds of training. Chamers and Lee (2004) reviewed WBT in the late 1990s by studying examples from several American corporations. Chan and Ngai (2007) discussed the implementation of WBT in ten different organizations in Hong Kong, one of which was in business with heavy machinery. In the past two decades, the content management system (CMS) concept has evolved due to the importance of managing and maintaining data available on the internet (Fernandes and Vidyasagar, 2015a). Therefore, it is important not only to develop a web application, but also to consistently manage and manipulate its content. A CMS represents a computer application that enables content by using a central interface; this allows one to build an online computer program that is easier to use and offers more functionality than a regular website. For example, content management systems can be employed for user and media management. As outlined by Manoj and Asoke (2016a), there are two primary components of a CMS: a content management application (CMA) and a content delivery application (CDA). The CMA assists in creating, modifying, and deleting content. As such, a person who is managing the content (as an administrator) can create new content and organize existing content, even without prior programming skills. The CDA updates the website and allows its content to be utilized. Some of the advantages of the CMS include time-saving in terms of developing the content, the possibility to create strong passwords for security reasons, and the use of themes and plugins that can support the process of creating or changing the CMS. Figure 1 oulines the web content management system (Manoj and Asoke, 2016b). The person who is creating and organizing content utilizes coding skills, manipulates the database (by inserting new material such as images, videos, sound files, and text), and uses different plugins and templates to create the website. Therefore, the application, database, and server are establishing the back-end capabilities. Such an application can then be presented in a front-end environment. Here, the term ‘front end’ alludes to the user interface; the visitors can directly interact with the website only to see the data, objects, and other content inserted by the content organizer. Even though the front end and back end serve different purposes in the process of creating web applications, both should be user-friendly and easily accessible. After set-up, the CMS generally does not require specialized technical skills. The content manager can create, sustain, and organize the website without having coding knowledge. Such knowledge is, of course, helpful for improving the quality of the website, but not essential. Today, with the rapid expansion of digital data and computer technology, a number of open-source CMA applications are publicly available and can be used to create and publish web-based software. CMS itself offers a practical solution for developing various types of websites and organizing their content. For example, blogging sites, portals, e-commerce sites, and enterprise websites can be developed within a CMS. Some of the currently popular CMS platforms include WordPress, Drupal, Magento, OpenChart, Wix, and Joomla. The main objective of this study was to show the potential of using the free and open-source CMS WordPress to create safety

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training courses in the mining industry. The specific research objectives were to: (i) Design and develop a web-based application for safety training purposes in the surface mining industry, emphasizing introduction to heavy machinery through pre-shift machine inspections (ii) Determine main and supplementary plugins useful for the application, then utilize them to create an application with different virtual tours and quizzes (iii) Describe the process of creating a training course through the developed template and give examples of developed courses.

Methodology We used a popular CMS called WordPress to develop the webbased training application. This CMS was created in 2003 as a blogging platform and became popular due to its user-friendly interface (WordPress, 2020). This paper shows the procedure by which the new training course was developed, what plugins were used, and how the developed application appears in a digital environment. Three experienced operators tested the developed application and reported universally positive feedback. The average age of the operators was fifty years and their average experience was twenty years.

The content management system (CMS) The most notable feature of WordPress is that no programming experience is needed to work within this platform. WordPress offers thousands of open-source plugins that can be utilized in the process of developing a given application. By incorporating this vast variety of plugins, WordPress offers tremendous potential for building a more efficient web-based program for the end-user. Plugins allow users to create content with ease, insert new content, modify the application, and to improve the application not only on PCs but also through mobile devices. Many authors have discussed and implemented WordPress in their research. Patel, Rathod, and Parikh (2011) analysed and compared three different CMS applications – WordPress, Joomla, and Drupal. In their statistical analysis, they stated that WordPress is the most suitable for live websites. Ghorecha and Bhatt (2013) investigated the same three applications and concluded that while each has some positive features, WordPress is most useful for its plugins.

Figure 1—Web content management system The Journal of the Southern African Institute of Mining and Metallurgy

Application of a content management system for developing equipment safety training courses Researchers have also utilized WordPress for different purposes. Namestovski, Takacs, and Arsovic (2012) presented the uses of WordPress and Moodle for e-learning. They stated that the large number of plugins, templates, and the flexible use of media are clear advantages of WordPress. They concluded that both platforms provide good support to traditional education. Avila et al. (2016) used WordPress to develop an ePortfolio environment to support learning in medical education. The authors found that it is possible to build a system that can be used for different activities, such as storing multimedia, web publishing, studying, etc. Fernandez and Vidyasagar (2015b) analysed the use of WordPress in the area of digital marketing, discussing WordPress plugins and how they can extend the use of WordPress to perform almost any task. Baines (2015) analysed the book WordPress for Libraries and stated that WordPress can be useful for organizing, searching, and accessing information. The author concludes that the use of WordPress will continue to expand. This variety of research conducted in different areas shows the potential of using WordPress for various purposes. Cabot (2018) stated that the research community has much to contribute to the future of WordPress and that there should be more research on the WordPress platform. In addition, different programming languages can be used to provide support in creating the application.

Development There were three major phases in building the web-based training application that would create and present training courses for heavy machine operators. Figure 2 shows the steps in creating the application with WordPress. The first phase was to install WordPress and set up the server with the database. At first a virtual server with database was used; then the application was placed on a live server. The second phase was designing the template of the application. First, the page builder was created and used to customize individual web pages. The page builder consists of three menu options – Courses, Instructions, and Contents. The options, which are not a default part of WordPress CMS, were specially developed for this project. These were inserted manually to create web pages in the application. Training manuals for different machines were handed out while designing the application. These contained information about the particular machines located at the mine site and included explanations and guidelines for the training of heavy machine operators. In addition to the training manuals, 360-degree images, videos, and standard 2D images were gathered to further supplement the training. Other template options – main and supplementary plugins – were also implemented within the developed web pages. Phase three, the final menu, is the result of phases one and two and presents a dashboard which consists of nine menu options (Figure 2). All of these nine options present in the template are used in the process of creating a new training course for the chosen mining machines. Training materials were then incorporated into a media library within the developed web application. These were used through the main plugins and the page builder in order to create different training courses. At this point, the researchers had yet to decide what plugins would best fit this project. As stated earlier, WordPress offers a large number of plugins that can be installed and used for The Journal of the Southern African Institute of Mining and Metallurgy

different purposes in the web-based application. Among these, we identified and selected the plugins that would be suitable as tools for the development of the new application. It was important to determine which WordPress plugins allowed for the use of 360-degree materials (images and videos). The advantages of the plugins and their simplicity of usage were considered. Thus, three appropriate plugins were selected for creating the training courses, two of which support 360-degree materials. The selected plugins are: ➤ iPanorama 360 (iPanorama 360, 2019) ➤ Wpvr (WordPress, 2019) ➤ Quizzes/Surveys Master (Quiz Master, 2019). Apart from these three plugins, a few supplementary plugins were added to improve user experience. Those plugins were‘Catch IDs’, ’Duplicate Post’, and ’Regenerate Thumbnails’. These additional plugins are not necessary to the functionality of the application; however, they improve the general user experience and user performance. A brief explanation of the main and supplementary plugins and the three default menu options that are utilized in the application is given in Figure 3.

Results and discussion The training template, developed as the main feature of the webbased training, allowed for the creation of a new training course for a specific machine. Before a new course can be created, any relevant media files must be first inserted into the program. This can be done by using the ’Media’ option from the menu. Users can either browse to add a new media file (a) or drag and drop a file (b), as indicated in Figure 4. After that, several steps (Figure 5) are followed in the process of creating a new course. The labels

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Figure 3—Description of plugins and default menu options

Figure 4—Insert media

Figure 5—Process of creating a new training course

‘a’, ‘b’, and so on in the following figures are either red or black and are used to mark the relevant options. The colour scheme changes to enhance visualizations by taking the background colour into consideration. Each menu option has a fillable form in which users can enter text and insert training materials such as MS Word or PDF documents, images, videos, etc. Users utilize the main plugins to create virtual tours and quizzes. Every virtual tour and quiz should be connected with its associated course.

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The first step in the process of creating a new training course (Figure 6) is by accessing the ’Courses’ menu option. Here, a course creator should first enter the course title (a) and the course name (b). The creator should then insert the course image (c), which is a 2D photo of a machine from the media library. Finally, a mine location (d) should be selected, and the new course can then be published (e). The second step employs the plugin ’iPanorama 360’ to create virtual tours for the machine inspections. This can be done by combining 360-degree images and 2D images (iPanorama 360, 2019). In the third step, after the user has created a virtual tour, it is necessary to create a post for the same tour. The menu option ‘Post’ (Figure 7) can be used to connect a virtual tour with a specific course (machine) so that the virtual tour can appear within the course. The title of the new post should now be added (a). In the label (b), a shortcode of the created virtual tour should be inserted. Every virtual tour has a unique shortcode that is generated automatically after the tour has been created. The shortcode is given in the following format: [iPanorama id=”000”]. The Journal of the Southern African Institute of Mining and Metallurgy

Application of a content management system for developing equipment safety training courses

Figure 6—Adding a new course – step 1

Figure 7—Creating a new post

The fourth step involves the creation of quizzes using the QSM plugin. Quiz questions will depend on training necessities and are derived from the training manuals for different machines. The fifth step requires the use of the ‘Wpvr’ plugin, which contains a video player that can show 360-degree training videos. In this example application, inserted videos were 10-15 minutes long and included information on pre-shift machine inspection. The sixth step is to connect the training course with the associated course name, relevant quizzes, and virtual tours that were created in earlier steps. Aside from these three factors, the menu option ‘Instructions’ is used to insert a document (training manual) into the course. In the seventh step, the menu option is used to insert the content of the page. This includes written explanations of particular instructions and 2D images. In the eighth step, the ‘navigation menu’ can be created to provide an easy, customized method of navigating the training course for future users. However, the creation of this menu is optional. Finally, permission levels and user roles are created and assigned. In WordPress, permission levels are highly The Journal of the Southern African Institute of Mining and Metallurgy

customizable based on the needs of the training software and software users. A software program can have one or more registered users. If the application is to be managed by multiple people, not every user should be authorized for full application control. As such, it is important to assign users certain roles so that every user knows their rights and permissions, as well as what changes to the application they can or cannot make. To increase the overall security of the web application, WordPress offers the ability to assign several levels of authorization to each user. This feature prevents unauthorized users from accessing the application. In addition, it does not allow the execution of tasks beyond a user’s permitted duties. The web-based training application in this study proposed the following three levels of permission for users and their roles: ➤ Administrator role ➤ Editor role ➤ Trainee role. The administrator role has the highest level of authority among all users. The administrator, who regulates the application, can monitor the complete dashboard and fully control both back-end and front-end content. Thus, an administrator VOLUME 120

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Application of a content management system for developing equipment safety training courses can make core changes related to coding, install new plugins, or delete existing ones. The administrator is also able to assign or change a user’s roles. The editor role is second to the administrator in terms of authority with a partial permission level. The editor can insert new content, create new training courses from the template, and modify existing courses. However, an editor cannot make essential application changes such as coding. A trainee has the lowest permission level. Thus, a trainee is only a visitor, lacking any authority to make changes to the content of the web application, courses, plugins, or code. A trainee is also not allowed to create a new course; they can only take an existing one. By using this approach, training courses were developed for machines that were widely used in the surface mine. The list of developed training courses is presented in Table I. Figure 8 shows the screen where users can select one of the developed training courses. Each course is designed for training on a single machine. Figure 9 shows that after selecting the training course, a trainee can click the button (a) to initiate training, and navigate through the selected course by using arrows or the navigation menu (d). The user can also choose another machine (b) and download a PDF version of the training manual for the selected machine (c).

Table I

List of developed courses Machine 1. 2. 3. 4. 5. 6. 7.

Haul Truck – CAT 789 Haul Truck – CAT 785 Dozer – CAT D10 Dozer – CAT D11 Scraper – CAT 16M Scraper – CAT 24M Surface miner – Wirtgen 4200

A trainee can read, listen, watch training videos, and take virtual tours related to the selected training course. Figure 10 shows an example of a virtual tour. During the virtual tour, a user can move between 360-degree images by using hotspots (a) to observe different machine parts. Hotspots can be followed by voice information about major machine parts. The system tracks what images are visited during a virtual tour. When a blue square (b) appears, it indicates that this location has been visited. Therefore, the user knows what areas of the tour are still left to be checked. A trainee can go into the non-full screen or full-screen mode (c) and use an image thumbnail slider (d) as a second option for navigating between scenes. These concepts have been applied to all the virtual tours created for the chosen

Figure 8—Course selection screen

Figure 9—Training course screen

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Application of a content management system for developing equipment safety training courses

Figure 10—Virtual tour – dozer

machines. Figures 11 and 12 give examples from a 360-degree virtual tour, presenting different details that can be observed by users. 360-degree videos on the machine inspection process were inserted into the courses using the Wpvr plugin as explained earlier. Such training videos allow a person to get a closer look at a machine and learn more about the pre-shift inspection process. Video screenshots from haul truck and dozer inspections are shown in Figure 13. It is also possible to take quizzes created with the QSM plugin. Quizzes are given at the end of training courses, assessing a trainee’s knowledge about the information they received through training manuals, virtual tours, and videos. The

results of the quiz are sent to an administrator by e-mail directly after a trainee submits their quiz responses; further steps should be determined by the trainer. Figure 14 shows an e-mail that includes a trainee’s name, test score, time taken to finish a quiz, and the quiz questions paired with the trainee’s responses. This web application has the potential to support traditional training provided to machine operators by presenting written information, virtual tours, videos, and knowledge assessment quizzes in one place. Modifications or improvements of the training courses can also be made with ease. The results of this research project show that it is possible to utilize CMS WordPress to develop a template and to create training courses. These in turn would help in introducing machine operators to machinery and the pre-shift machine inspection process in surface mining. Potential users of such applications can develop new training courses, or change existing courses, without needing programming skills. Users can also remove or insert materials directly into the media database. It is beneficial to introduce machine operators to machinery and major daily procedures in the office environment before they go into the field. This will promote safety awareness. For instance, from a safety standpoint, some new operators might not have seen these machines previously, and this training approach could help familiarize them with the important parts of the machinery by using a mix of 360-degree images, videos, and training documents. The plugins and WordPress are upgraded

Figure 11—Dozer – side and cabin views

Figure 12—Haul-truck – side and underneath views

Figure 13—360-degree video – haul-truck inspection and dozer inspection The Journal of the Southern African Institute of Mining and Metallurgy

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Application of a content management system for developing equipment safety training courses ➤ Development of custom-made plugins as a replacement for available WordPress plugins. ➤ Discussion on further uses for the developed application.

Acknowledgements This research was supported by a mining company in the USA.

References Ammoyun, O. and Careddu, N. 2014. Mine simulation for educational purposes: a case study. Computer Applications in Engineering Education, vol. 23, no. 2. pp. 286–293. Avila, J., Sostmann, K., Breckwoldt, J., and Peters, H. 2016. Evaluation of the free, open-source software WordPress as electronic portfolio system in undergraduate medical education. BMC Medical Education, vol. 16, no. 157. pp. 1–10. Baines, S.A. 2016. WordPress for libraries. Hafaele, C. (ed.). Journal of Access Services, vol. 13, no. 3. pp. 213–214. Brnich, M., Derick, R.L., Mallet, L., and Vaught, C. 2002. Innovative alternatives to traditional classroom health and safety training. Strategies for improving miners’ training. Peters, R.H. (ed.). US Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No 2002-156, Information Circular 9463, 03 September 2002. pp. 19–25. Cabot, J. 2018. WordPress: A content management system to democratize publishing. Institute of Electrical and Electronics Engineers Software, vol. 35, no. 3. pp. 89–92. Chamers, T., and Lee, D. 2004. Web-based training in corporations: organizational considerations. International Journal of Instructional Media, vol. 31, no. 4. pp. 345–354.

Figure 14—Quiz results sent on e-mail address

periodically to newer versions, and therefore they can be updated by a user. Ordinarily, a user would not have issues while updating the plugin. However, updates are not required, and the application is operable without newer versions of the plugins or CMS. The developed application is not only useful for developing safety training courses related to surface mining machines. It can potentially be used for other training and educational purposes – for example, it could be used for virtual tours of a mine site, as well as in other industries.

Conclusions The web-based application developed through this research project can support traditional safety training by introducing machine operators to the different surface mining machines they will eventually operate in the field. The application is highly flexible for creating and editing training courses. An emphasis was placed on virtual tours and 360-degree videos that could assist in learning about machines and pre-shift inspections. The outcomes of using CMS can be summarized as follows: ➤ Several plugins, along with default WordPress features, are identified, explained, selected, and used to create the application and training template. ➤ The process of developing new training courses in several steps, without prior coding skills, is explained. ➤ The developed application is deployed on a web server, allowing both online and offline access. Future research and improvements to this web-based training could include: ➤ Further investigation and implementation of other useful plugins, which could widen the use of the developed application

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Chan, S.C.H. and Ngai, E.W.T. 2007. A qualitative study of information technology adoption: how ten organizations adopted web-based training. Information Systems Journal, vol. 17, no. 3. pp. 289–315. Fahy, P.J. 2004. Web-based training. The Internet Encyclopedia. Bidgoli, H. (ed.). vol. 3, pp. 661-673. Fernandes, S. and Vidyasagar, A. 2015. Digital marketing and WordPress. Indian Journal of Science and Technology, vol. 8, no. S4. pp. 61–68. Gao, Y., Fan, Y.X., Wang, J., Li ,X., and Pei, J.J. 2019. The mediating role of safety management practices in process safety culture in the Chinese oil industry. Journal of Loss Prevention in Process Industries, vol. 57. pp. 223–230. Ghorecha, V. and Bhat, C. 2013. A guide for selecting content management system for web application development. International Journal of Advance Research in Computer Science and Management Studies, vol 1, no. 3. pp. 13–17. iPanorama360. 2019. https://codecanyon.net/item/ipanorama-360-virtual-tourbuilder-for-wordpress/17028820 Kral, S. 2002. Improved training reduces worker injuries. Mining Engineering, vol. 54, no. 10. pp. 23–26. Manoj, S. and Asoke, N. 2016. Web content management system. International Journal of Innovative Research in Advanced Engineering, vol. 3, no. 3. pp. 51–56. Namestovski. Z., Takacs, M., and Arsovic, B. 2012. Supporting traditional educational process with e-learning tools. Proceedings of the 10th Jubilee International Symposium on Intelligent Systems and Informatics, Subotica, Serbia, 20-22 September 2012. Institute of Electrical and Electronics Engineers. pp. 461–464. Patel, S.K., Rathod, V.R., and Parikh, S. 2011. Joomla, Drupal and WordPress - a statistical comparison of open source CMS. Proceedings of the 3rd International Conference on Trends in Information Sciences & Computing. Institute of Electrical and Electronics Engineers. pp. 182–187. Peters, H.R., Vaught, C., and Mallet, L. 2010. A review of NIOSH and U.S. Bureau of Mines research to improve miners’ health and safety training. Extracting the Science: A Century of Mining Research. Brune, J.F. (ed.). Society for Mining, Metallurgy, and Exploration, Inc., Littleton, CO. pp. 501-509. Quiz Master. 2019. https://wordpress.org/plugins/quiz-master-next/ Zhang, M. and Kecojevic, V. 2016. Intervention strategies to eliminate truck-related fatalities in surface coal mining in West Virginia. International Journal of Injury Control and Safety Promotion, vol. 23, no. 2. pp. 115–129. WordPress. 2019. WP VR – 360 Panorama and virtual tour creator for WordPress. https://wordpress.org/plugins/wpvr/ WordPress. 2020. Features. https://wordpress.org/about/features/

The Journal of the Southern African Institute of Mining and Metallurgy

An exploration of women’s workplace experiences in the South African mining industry S. Mangaroo-Pillay1 and D. Botha1 Affiliation: 1 School for Social Sciences, North-West University, Potchefstroom. Correspondence to: D. Botha

Email:

Doret.Botha@nwu.ac.za

Dates:

Received: 21 Jan. 2020 Revised: 12 Aug. 2020 Accepted: 13 Aug. 2020 Published: August 2020

How to cite:

Mangaroo-Pillay, S. and Botha, D. An exploration of women’s workplace experiences in the South African mining industry. The Southern African Institute of Mining and Metallurgy DOI ID: http://dx.doi.org/10.17159/24119717/1099/2020 ORCiD ID: S. Mangaroo-Pillay https://orchid.org/0000-00015994-6691 ORCiD ID: D. Botha https://orchid.org/0000-00032787-8107

Synopsis Historically, the mining industry, on a global level, was male-dominated, as many governments had prohibited women from working at mines, particularly underground. In South Africa, the government introduced the Mineral and Petroleum Resources Development Act (No. 28 of 2002) (MPRDA) and the Broad-based Socio-economic Empowerment Charter to address the imbalances and rectify previous inequalities in the mining industry. Since the inception of MPRDA, women’s representation in the South African mining industry has increased, from 3% in 2002 to 15% in 2018. Although government has good intentions, gender equality in the mining industry remains a challenge. Research on women employed in South African mines revealed that women still face barriers to some extent. This research explores women’s current workplace experiences in the South African mining industry. A literature review and an empirical study were conducted. The study followed a positivistic research approach, and a quantitative research design was used. Self-administered questionnaires were distributed at the 8th Annual Women in Mining Conference in February 2017. Based on the data obtained, it became evident that several aspects must still be addressed to successfully accommodate women in the mining workplace. The study offers practical recommendations that can be implemented by mining organizations to improve women’s workplace experiences in order to encourage and foster transformation in the mining industry. Keywords gender, mining industry, mining legislation, South Africa, women in mining.

Introduction Historically, the mining industry, on a global level, was male-dominated, as many governments had prohibited women from working at mines, particularly underground. The International Labour Organization (ILO) adopted Convention 45 of 1935 on 21 June 1935 in Geneva, which prohibited the employment of women for underground work in mines of all kinds (ILO, n.d.). In South Africa, the South African Minerals Act (No. 50 of 1991) also forbade women from underground work (ILO, n.d.; South Africa, 1991). In 2002, the Mineral and Petroleum Resources Development Act (No. 28 of 2002) (MPRDA) and the Broad-based Socio-economic Empowerment Charter (signed in 2002 and published in 2004) were introduced to address the imbalances in the industry, calling for 10% of the workforce to be women by 2009 (South Africa, 2002, 2004a). From 2002, women’s representation in the South African mining industry increased from 3% to 15% in 2018 (Minerals Council South Africa, 2018, p. 41). Although considerable progress has been made in terms of women’s representation in the South African mining industry, men still dominate this industry. Furthermore, research conducted on women employed in South African mines since the inception of the MPRDA in 2002 has revealed that the employment of women remains a challenge and that women still face barriers to some extent (Botha, 2016, 2017; Botha and Cronjé, 2015; Chamber of Mines of South Africa, 2017; Hancock, 2014; Kolisi and Rithaa, 2016; Mavuso, 2015; Ntombela, 2014).

Purpose of the study The study on which this article reports was conducted to explore women’s current workplace experiences in the South African mining industry. The article begins with an overview of global and national mining legislation pertaining to female workers, followed by an outline of gender barriers in the South African mining industry since the inception of the MPRDA. Thereafter, the empirical results are presented and discussed. The article concludes with practical recommendations to improve women’s workplace experiences in the mining industry. The Journal of the Southern African Institute of Mining and Metallurgy

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An exploration of women’s workplace experiences in the South African mining industry Overview of mining legislation pertaining to female workers: A global and national perspective The mining industry world-wide has been considered a masculine industry for many years. As a result, mining jobs have neither been desired as an occupation by women, nor easily awarded to women. However, significant developments in mining legislation have taken place over the past few years in many countries, including South Africa, in an attempt to address the inequalities in the industry and to bring women into the industry.

Mining legislation: A global perspective There is no global legislation specifically pertaining to women in the mining industry, because each country has its own legislation. However, according to the International Labour Organization (ILO, 2011, p: ix), there are continual legislative efforts, repeated institutional initiatives, and a growing awareness of the need to overcome discrimination in the workplace. Race and sex continue to be the grounds of discrimination included in most equality legislation in an attempt to remove discrimination in the workplace (ILO, 2011; SAHRC, 2017; United Nations, 2019). Worldwide, new laws were introduced and existing legislation amended to abolish discrimination based on maternity, marital status, lifestyle, and genetic predisposition, and new policies introduced for training and improving employment quotas for women in managerial positions (ILO, 2011; SAHRC, 2016; United Nations, 2003). However, the benefits for women are not enough. Although these policies have been implemented they are not functioning effectively, because many institutions suffer a shortage of financial and human resources as well as insufficient policy coherence at local and national levels. Labour authorities, such as inspectors and public officials, lack knowledge and institutional capacity when addressing discrimination cases, which deters victims of discrimination from submitting claims (ILO, 2011, p. x; SAHRC, 2016, p. 7, 69; United Nations, 2003, p. 633, 2011, p. 138). The ILO’s Convention 45 of 1935 prohibited the employment of women in underground mining work (ILO, n.d.), but many countries that initially ratified it have since denounced it (Chamber of Mines of South Africa, 2017, p. 1). These countries include Australia (1988), Canada (1978), Chile (1997), and South Africa (1996), among others (Chamber of Mines of South Africa, 2017, p. 1).

Mining legislation: A national perspective In 1898 the South African Republic, which ruled the Transvaal, in its Act No. 12 (XVIII:146), explicitly banned the employment of women in any mine. The relevant clause, which was written in Dutch, was transferred almost word for word into the Union of South Africa’s Mines and Works Act (No. 12 of 1911) (par. 8.1). The clause read: ’No person shall employ underground on any mine a boy apparently under the age of sixteen years or any female’ (Alexander, 2007, p. 214). The Mines and Works Act (No. 27 of 1956) also forbade women to work underground. Section 11 (1) read: ‘No male person under the age of sixteen years and no female shall work, and no person shall cause or permit any male person apparently under the age of sixteen years or any female to work, underground in any mine’ (South Africa, 1956, p. 61). However, Section 32 (2) of the Mines and Works Act (No. 27 of 1956) allowed women to work underground if they held management positions, if they were employed in health

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and welfare services, for training purposes, and if they had to go underground in a mine for the purposes of non-manual occupations (South Africa, 1956, p. 55). The Mines and Works Act (No. 27 of 1956) was repealed by the Minerals Act (No. 50 of 1991). The MPRDA replaced the Minerals Act (No. 50 of 1991) and came into effect on 1 May 2004. Among others, the objectives of the Act are to ‘promote equitable access to the nation’s mineral and petroleum resources to all the people of South Africa’ and to ’substantially and meaningfully expand opportunities for historically disadvantaged persons, including women, to enter the mineral and petroleum industries and to benefit from the exploitation of the nation’s mineral and petroleum resources’ (South Africa, 2002, p. 18). The term ‘historically disadvantaged South Africans’ (HDSAs) refers to ‘any person, category of persons or community, disadvantaged by unfair discrimination before the introduction of the Constitution of the Republic of South Africa (Act 200 of 1993) came into operation’ (South Africa, 2004a, p. 8). To give rise to Section 100 (2) (a) of the MPRDA, the Department of Minerals and Energy introduced the Mining Charter (Fauconnier and Mathur-Helm, 2008; South Africa, 2004a). This legislation was then followed by the Scorecard (Notice 1639 of 2004), which set the framework, targets, and timetable against which mining companies needed to report and were measured (South Africa, 2004b). In terms of Section 4 of the Scorecard (Notice 1639 of 2004), mining houses were required to ‘implement career paths to provide opportunities to their HDSA employees to progress in their chosen careers’ and to ’ensure a higher level of inclusiveness and advancement of women’ (South Africa, 2004b, p. 11). A minimum requirement of 10% female participation in the mining industry within five years (which was due in 2009) was set (South Africa, 2004b, p. 12). In 2009 and 2015, the Department of Mineral Resources conducted impact assessments to establish the progress in the South African mining industry regarding the objectives of the Mining Charter (DMR, 2009, 2015). The findings of the reports showed that, in as much as the Mining Charter was a valuable tool for improving transformation in South Africa’s mining industry, there were challenges in terms of effective implementation in order to meet its objectives. It was then recommended that the Mining Charter be reviewed and strengthened. This resulted in amendments of the Broad-based Socio-economic Empowerment Charter for the South African Mining and Minerals Industry in 2010 (South Africa, 2010) and 2015 (MHSC, 2015). New employment equity targets were set in each charter. Although the percentage of women participating in mining improved from 3% in 2002 (Minerals Council South Africa, 2018, p. 41) to 6% in 2009 (DMR, 2009, p. 9) and to 10.5% in 2014 (DMR, 2015, p. 28), the employment figures for women were low in each employment functional category (top management [board] level, senior management [EXCO] level, middle management level, junior management level, and in core skills) (DMR, 2015, p. 27). On 15 June 2017, the Reviewed Broad-based Black Economic Empowerment Charter for the South African Mining and Minerals Industry, 2016 (named the Reviewed BBBEE Mining Charter) was published. However, there was much uncertainty and controversy around the new Charter. On 27 September 2018, the Broad-based Socio-economic Empowerment Charter for the Mining and Minerals Industry, 2018 (Mining Charter 3) was published and came into force on 1 March 2019, almost three The Journal of the Southern African Institute of Mining and Metallurgy

An exploration of women’s workplace experiences in the South African mining industry years after the publication of the first draft (Bulbulia, 2019). Mining Charter 3 requires a minimum of 50% HDSAs at board level with exercisable voting rights (20% should be women), a minimum of 50% at executive management level (20% women), 60% at senior management level (25% women), 60% at middle management level (25% women), and 70% at junior management level (30% women) (South Africa, 2018, pp. 22–23).

Gender barriers in the South African mining industry since the inception of the MPRDA

Although great efforts have been made to accommodate women in the South African mining industry since the inception of the MPRDA in 2002, the literature reviewed indicates the following main barriers that women continue to face. ➤ Women working in core mining areas, specifically underground, are often seen as sexual objects and experience physical, verbal, and non-verbal sexual conduct as well as quid pro quo harassment on a regular basis (Botha, 2016; Botha and Cronjé, 2015; Creamer Media, 2019; Jones and Moalusi, 2019; Minerals Council South Africa, 2019; Nene, 2016; Ntombela, 2014). ➤ Although mining companies made considerable progress in accommodating women by providing personal protective equipment (e.g. overalls, dust masks, and safety boots) designed for women, improvements are still needed in this regard. Furthermore, a need for protective clothing for pregnant women is identified (Botha, 2017; James, 2018; MHSC, 2015). ➤ Frequently, the physical strength required for many mining tasks precludes women from performing these tasks effectively (Jones and Moalusi, 2019, p. 3 MHSC, 2015, p. 5; Minerals Council South Africa, 2019 p. 3). Difficult jobs such as operating rock drills, locomotives, and dozers may hold physiological risks for women (Botha and Cronjé, 2015, p. 10; Matshingane, 2017, p. 3; Minerals Council South Africa, 2019, p. 3; Chamber of Mines of South Africa, 2017, p. 2). ➤ A lack of separate, decent, and hygienic toilet facilities underground is often reported (Botha, 2017, p. 22; Matshingane, 2017, p. 5; MHSC, 2015, p. 64; Minerals Council South Africa, 2019, p.3). ➤ The mining industry often constitutes an unattractive work environment because of issues such as discrimination against women, sexual harassment, and prejudice due to marital status and/or maternity (Botha, 2016; Creamer Media, 2019; Jones and Moalusi, 2019; Mavuso, 2015; MHSC, 2015). A negative work environment contributes towards the number of women leaving their jobs, resulting in slower transformation of the mining industry (Breytenbach, 2017; Mputing, 2017). ➤ Female workers’ negative perceptions with regard to safety and the nature of equipment contribute to turnover once employees consider the accidents or consequnces that are likely to occur, thereby causing them to fear injury or fatality (Matshingane, 2017; Mavuso, 2015; Minerals Council South Africa, 2019). ➤ Women often find it difficult to balance their work and personal lives and/or activities (e.g. family, domestic activities, and health). Unfriendly working hours (shift work and working off-hours) and the physicality of mine work complicate this issue (James, 2018; Jones and Moalusi, 2019; Matshingane, 2017; Mavuso, 2015). The Journal of the Southern African Institute of Mining and Metallurgy

➤ Inadequate training and career development support (e.g. bursaries, study leave, and mentoring systems) are frequently reported (Jones and Moalusi, 2019; Matshingane, 2017; Mavuso, 2015; Slater, 2018).

Research methodology The study followed a positivistic research approach. It was informed by the ontological approach of objectivism and the epistemology of empiricism. A quantitative research design was used. This study encompassed a literature review and an empirical study.

Target population and sampling The target population consisted of women employed at mines in South Africa who attended the 8th Annual Women in Mining Conference held on 22 February 2017. This study was based on a non-probability convenience sample, because it was ‘available to the researcher by virtue of its accessibility’ (Bryman et al., 2015, p. 178). The sample consisted of 129 women who attended the Conference.

Instrumentation and data collection Data was collected by means of self-administered questionnaires. The questionnaires were aimed at obtaining biographical information as well as information on the perceptions of women’s workplace experiences in the mining industry, based on a fivepoint Likert-type scale rating, ranging from ‘strongly disagree’ to ‘strongly agree’.

Data analysis and reporting The Statistical Package for the Social Sciences (SPSS Version 24) was used to process the data. A factor analysis was conducted to explore the underlying structure of women’s workplace experiences in the mining industry. Cronbach’s alpha coefficients were used to determine internal reliability. In addition, descriptive statistics, t-tests, analyses of variance (ANOVAs), and correlations were used to analyse the data. To determine whether differences in means were important in practice, Cohen’s d-values were used as effect size, where d = 0.2 was considered as small, d = 0.5 as medium, and d = 0.8 as large effects (Cohen, 1988). According to Cohen (1988), correlations of 0.1, 0.3, and 0.5 can be interpreted as small, medium and large correlations, respectively.

Ethical considerations Permission to conduct the research was obtained from the Intelligence Transfer Centre, which hosts the Annual Women in Mining Conference. The succeeding ethical practices were factored in the study: voluntary participation, anonymity, and informed consent (see Babbie and Mouton, 2011, p. 12).

Empirical results Biographical Information Table I presents the biographical information of the respondents.

Perceptions of women’s workplace experiences in the South African mining industry Validity and reliability A factor analysis was conducted on the 35 Likert-type scale items measuring perceptions of women’s workplace experiences in the South African mining industry. Principal component analysis and VOLUME 120

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An exploration of women’s workplace experiences in the South African mining industry Table I

Biographical information Item

Category

North West Western Cape Northern Cape Eastern Cape KwaZulu-Natal Gauteng Limpopo Mpumalanga Free State

26 0 17 1 1 25 17 19 6

23.2 0.0 15.2 0.9 0.9 22.3 15.2 17.0 5.4

Mining sector

Gold Platinum Coal Uranium Copper Other

13 27 26 0 2 57

10.4 21.6 20.8 0 1.6 45.6

Gender

Male Female 128 Other

0 100 0

Province working in

Age

< 20 years 21–30 years 31–40 years 41–50 years 51–60 years

1 23 72 27 4

0.8 18.1 56.7 21.3 3.1

Black White Coloured Indian Other

104 8 7 3 2

83.9 6.5 5.6 2.4 1.6

Highest qualification

Matric and below Diploma Degree Honours Master’s/Doctorate

34 30 25 20 19

26.6 23.4 19.5 15.6 14.8

Level of employment at the mine

Unskilled worker Semi-skilled worker Skilled worker Junior management Middle management Senior management Top (executive) management

2 15 26 27 36 16 2

1.6 12.1 21.0 21.8 29.0 12.9 1.6

Intern / Graduate / Learner official Miner Shift boss / Mine overseer Manager: Mining Other

7 9 5 8 95

5.6 7.3 4.0 6.5 76.6

< 5 years 6–10 years 11–20 years 21–30 years 30 > years

25 58 38 3 2

19.8 46.0 30.2 2.4 1.6

< R5 000 R5 001–R10 000 R10 001–R20 000 R20 000–R40 000 > R40 000

1 14 24 44 39

0.8 11.5 19.7 36.1 32.0

Underground Work on surface Work underground and on surface Work in other areas

7 81 21 17

5.6 64.3 16.7 13.5

Open pit Deep mining (underground)

55 48

53.4 46.6

Belong to a union Do not belong to a union

70 54

56.5 43.5

Race

Current role in mining

Years working in the mining industry

Income

Place of work on mines

Open pit or deep mining (underground)

Union affiliation

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oblimin rotation were used. The Kaiser-Meyer-Olkin test (KMO) gave a measure of 0.785 and indicated that the sample size was adequate for factor analysis. Values for KMO between 0.7 and 0.8 are excellent (Field, 2005, p. 640). The p-value of Bartlett’s test of sphericity returned a value smaller than 0.05, suggesting that the correlation between statements was sufficient for factor analysis (see Field, 2005). Five factors (Transformation, Female abuse, Personal care, Career choice, and Development and training) were extracted through Kaiser’s criteria (see Field, 2005) that explained 51.84% of the total variance. The results of the factor analysis are reported in Table II. The Cronbach’s alpha coefficient for the Transformation, Female abuse, Personal care, and Development and training factors calculated well above the required 0.7, and showed high reliability and internal consistency. The Career choice factor showed a Cronbach’s alpha coefficient of 0.629, which could be regarded as an acceptable reliability. This might have been caused by the low number of statements, namely two in the factor. The mean inter-item correlation was 0.459, which is sufficient according to Clark and Watson (1995). The interitem correlations should be in the range of 0.15 to 0.55 to be considered as an indicator for an acceptable level of consistency (Clark and Watson, 1995, p. 8). For the descriptive statistics, the following response categories were used: 1 = strongly disagree, 2 = disagree, 3 = neutral, 4 = agree, and 5 = strongly agree. Mean scores below 2.5 indicate that most respondents disagreed with the statements contained in the factors, while mean scores above 2.5 indicate that most respondents agreed with the statements. The mean scores of all the factors measured above 2.5 (Transformation: M = 3.114; Female abuse: M = 3.068; Personal care: M = 3.175; Career choice: M = 2.515; Development and training: M = 3.237).

Correlation between age, highest qualification, level of employment, years working at the mine, income, and workplace experiences The Spearman rank correlation test was used to measure the linear association between age, highest qualification, level of employment, years working at the mine, income, and women’s workplace experiences in the South African mining industry. The results are reflected in Table III. Small positive correlations were found between income and Transformation (p = 0.018, r = 0.214) and income and Development and training (p = 0.028, r = 0.202). Medium to large positive correlations were found between Transformation and Personal care (p = 0.000, r = 0.486), Transformation and Development and training (p = 0.000, r = 0.554), and Personal care and Development and training (p = 0.001, r = 0.300). Small negative correlations were found between Transformation and Career choice (p = 0.030, r = –0.194); Personal care and Career choice (p = 0.034, r = –0.189) and Female abuse and Personal care (p = 0.039, r = –0.183). A moderate negative correlation was found between Transformation and Female abuse (p = 0.000, r = –0.358).

Effect of working in an open pit or deep underground mine) on women’s workplace experiences From the results of the t-test, it is evident that the p-values for all the factors of women’s workplace experiences in the mining industry were higher than 0.05, indicating that there were no statistically significant differences between the means of The Journal of the Southern African Institute of Mining and Metallurgy

An exploration of women’s workplace experiences in the South African mining industry Table II

Pattern matrix: Women’s workplace experiences in the South African mining industry

Statement

Factor

abuse

care

choice

and training

Transformation Female Personal Career Development

Management reminds employees about the importance of women in the organisation.

0.851

Transformation is at the top of this organisation’s agenda.

0.796

Management encourages employees to embrace diversity.

0.783

I feel that women’s inputs are valued in the organisation.

0.732

Q21 ®

Taking child responsibility leave is a problem.

0.602

The facilities at the organisation are conducive to women to work in.

0.515

Q20

Male managers understand that I am also a mother with responsibilities.

0.502

Q29

Management involves women in decision making.

0.398

Q10

There are good relations between female and male management.

0.391

Women get promoted more easily than men.

0.352

Q11

Male managers dominate the work environment.

0.601

Women in management need to work extra hard to prove themselves.

0.577

Q19

Male workers emotionally abuse me at times.

0.568

Q17

Male workers harass women.

0.552

Men in the workplace think women are weak.

0.503

Q16 ®

It is easy for women to communicate with men in the workplace.

0.446

Q9 ®

There are good relations between female and male miners.

0.388

Q18

I am a victim of sexual and/or physical harassment.

0.311

Q12

The female miners’ uniforms are comfortable for them to work in.

0.864

Q13

Personal protective equipment and clothing have been designed especially for women.

0.839

Q15

The toilets at the workplace are suitable for women underground.

0.554

Q23

The organisation has made changes to accommodate women.

0.450

Q14

The toilets at the workplace are suitable for women on the surface.

0.252

Q33

I am forced to work at the mines, as the income is good.

0.709

Q34

Given the chance, I will not work at a mine.

0.680

Q30

I have a career development plan in place.

–0.697

Q25

My manager is keen to approve studies for women.

–0.680

Q31

I am on a mentorship programme.

–0.651

Q26

The organisation offers training programmes for women.

–0.627

Q24

My manager supports women’s development in their careers.

–0.615

Q28

Programmes are in place to address gender inequalities.

–0.293

Cronbach’s alpha

0.862

0.722

0.747

0.629

0.778

Factor mean

3.114

3.068

3.175

2.515

3.237

Factor standard deviation

0.869

0.665

0.878

1.203

0.897

Extraction method: principal component analysis Rotation method: oblimin with Kaiser normalization Rotation converged in 22 iterations

respondents working in an open pit or in deep mining. However, the effect size for Transformation (d = 0.30) and Personal care (d = 0.35) showed a small effect, indicating that women working in an open pit were slightly more satisfied with Transformation (M = 3.21) and Personal care (M = 3.33) than those working in deep (underground) mining (Transformation: M = 2.93; Personal care: M = 2.99).

Effect of affiliation to a union y The results of the t-test indicated no statistically significant differences between the means of respondents that were affiliated to a union and those that were not, as the p-values for all the factors of women’s workplace experiences in the mining industry calculated higher than 0.05. The effect sizes for Transformation The Journal of the Southern African Institute of Mining and Metallurgy

(d = 0.31), Personal care (d = 0.33), and Development and training (d = 0.24) showed a small effect. Women affiliated to a union were less satisfied with Transformation (M = 2.96), Personal care (M = 3.04), and Development and training (M = 3.13) than those not affiliated (Transformation: M = 3.25; Personal care: M = 3.33; Development and training: M = 3.35).

Effect of race The t-test yielded p-values higher than 0.05 for all the factors of women’s workplace experiences in the mining industry, indicating no statistically significant differences between the means of ‘black’ respondents and respondents of ‘all other racial groups’. The effect sizes indicated a small effect for Transformation (d = 0.32), Female abuse (d = 0.29), and Career VOLUME 120

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An exploration of women’s workplace experiences in the South African mining industry Table III

C orrelation between age, highest qualification, level of employment, years working at the mine, income, and women’s workplace experiences in the South African mining industry Age Highest Level of Years Income Transformation Female Personal Career Development qualification employment working abuse care choice and at mine training Correlation coefficient

0.068

0.096

0.168

0.062

0.214* (a)

Transformation

Sig. (2-tailed)

0.446

0.281

0.062

0.493

0.018

128

124

126

0.148

0.133

0.071

0.165

0.095

0.142

0.429

0.070

0.000

128

124

126

122

129

Female abuse

Correlation coefficient –0.009

Sig. (2-tailed)

N Personal care

127 0.918 127

1.000

–0.358**(b) 0.486**(b) –0.194*(a)

122

129 –0.358**(b)

0.000

0.030

129

127

126

0.167

–0.103

0.039

0.062

0.250

127

126

1.000

0.044

0.079

0.108

0.102

0.132

0.486**(b)

Sig. (2-tailed)

0.629

0.380

0.236

0.258

0.151

0.000

0.039

126

122

124

120

127

Career choice

–0.183*(a)

127

126 –0.103

0.020

Sig. (2-tailed)

0.770

0.477

0.538

0.669

0.830

0.030

0.062

0.034

125

121

123

119

126

0.054

0.150

–0.001 0.202*(a)

0.554**(c)

0.547

0.100

0.988

0.028

0.000

0.250

0.001

0.251

125

121

123

119

126

Sig. (2-tailed) N

0.736 124

0.001

1.000

0.039

–0.189*(a)

0.300**(b)

126

–0.056

126

0.034

0.064

–0.103

0.000

–0.189*(a)

0.027

Development and training Correlation coefficient –0.031

0.167

1.000

Correlation coefficient

124

–0.194*(a)

–0.183*(a)

129

Correlation coefficient

125

0.554**(c)

0.000

0.251

126

0.300**(b) –0.103

1.000 126

** Correlation is significant at the 0.01 level (2-tailed) * Correlation is significant at the 0.05 level (2-tailed) (a) small effect: r = 0.1, (b) medium effect: r = 0.3 and (c) large effect: r > 0.5 s

choice (d = 0.27). Black respondents (M = 3.05) were less satisfied with Transformation than ‘all other racial groups’ (M = 3.34), agreed more (M = 3.11) than ’all other racial groups’ (M = 2.89) that Female abuse is a problem in the workplace, and indicated more (M = 2.58) than ’all other racial groups’ (M = 2.24) that working at the mine is not their preferred Career choice.

Effect of the mining sector The results of the ANOVA indicated p-values higher than 0.05 for all the factors of women’s workplace experiences in the mining industry, indicating no statistically significant differences between the means of the different mining sectors. The results of the effect sizes indicated a small effect for Transformation, where the respondents from the platinum mining sector (M = 3.26) were slightly more positive about Transformation than those from the coal (M = 2.98, d = 0.28) and the gold mining sectors (M = 2.88, d = 0.39). The Female abuse factor showed a small effect, where the respondents from the platinum mining sector (M = 3.14) agreed more than respondents from the coal mining sector (M = 2.98, d = 0.20) with the statements in the Female abuse factor. The effect size for the Personal care factor showed a small effect for all the mining sectors, where respondents from the gold mining sector (M = 2.85) were less positive about Personal care than those from all the other mining sectors (platinum: M = 3.35, d = 0.48; coal: M = 3.13, d = 0.27; other: M = 3.19, d = 0.33). The effect size for the Development and training factor indicated a small effect, where the respondents from coal mining sector (M = 3.03) were less positive about Development and training opportunities than those from all the other mining sectors (gold: M = 3.34, d = 0.4; platinum: M = 3.31, d = 0.29; other: M = 3.28, d = 0.28).

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Effect of place of work The results of the ANOVA indicated p-values higher than 0.05 for Female abuse, Career choice, and Development and training, indicating no statistically significant differences between the means of the workplace categories. However, the ANOVA indicated that the means of the workplace categories for Transformation (p = 0.005) and Personal care (p = 0.027) differed statistically significantly. The effect sizes for Transformation showed a medium to large effect, where respondents who worked underground as well as both underground and on the surface (M = 2.68) were less positive about Transformation than those who worked on the surface (M = 3.21, d = 0.61) and in other work areas (M = 3.42, d = 0.85). The effect size for the Personal care factor showed a small to medium effect, where respondents who worked on the surface (M = 3.33) were more positive about Personal care than respondents who worked underground as well as both underground and on the surface (M = 2.83, d = 0.57) and in other areas (M = 3.03, d = 0.35).

Effect of age The results of the ANOVA indicated no statistically significant differences between the means for the different age groups; the p-values were higher than 0.05 for all the factors. The effect sizes showed a small effect for Development and training (d = 0.27), where the age category 31–40 (M = 3.32) was more positive about the statements contained in these factors than the 41–60 (M = 3.07) age category.

Effect of highest qualification The results of the ANOVA indicated p-values higher than 0.05 for The Journal of the Southern African Institute of Mining and Metallurgy

An exploration of women’s workplace experiences in the South African mining industry Transformation, Personal care, Career choice, and Development and training, indicating no statistically significant differences between the means of the qualification categories. However, the p-value for Female abuse was 0.008, indicating that the means of the qualification categories differed statistically significantly. Female abuse showed a medium to large effect, where respondents with a matric or lower qualification (M = 2.79) agreed less with the Female abuse factor than respondents with a diploma (M = 3.20, d = 0.68), degree (M = 3.37, d = 0.96), or master’s and doctoral qualification (M = 3.13, d = 0.44).

Effect of level of employment The results of the ANOVA returned p-values higher than 0.05 for Transformation, Female abuse, Personal care, and Development and training, indicating no statistically significant differences between the means of the level of employment categories. However, the p-value for Career choice measured 0.035, indicating that the means of the level of employment categories differed statistically significantly. From the homogeneous subsets it was evident that the mean of respondents who were employed as senior managers (M = 2.02) differed significantly from the those of junior managers (M = 3.11). Career choice showed small to large effects, where respondents employed at senior management level (M = 2.02) disagreed the most with the statements contained in the Career choice factor, compared with employed on unskilled and semi-skilled (M = 2.44, d = 0.40), skilled (M = 2.30, d = 0.40), junior (M = 3.11, d = 0.26), and middle management (M = 2.57, d = 0.78) levels.

Effect of years working in the mining industry The results of the ANOVA indicated p-values higher than 0.05 for all the factors, indicating no statistically significant differences between the means of the different categories. The effect sizes showed a small effect for Personal care, where respondents with more than 11 years’ (M = 3.38) working experience were more positive about Personal care than those with fewer years’ (fewer than 5 years: M = 3.16, d = 0.21; 6–10 years: M = 3.02, d = 0.21) experience. Development and training showed a small effect, where respondents with fewer than five years’ working experience (M = 3.35) were more positive about Development and training than those with 6 to 10 years’ experience (M = 3.11, d = 0.25).

Effect of income The results of the ANOVA indicated p-values higher than 0.05 for Female abuse, Personal care, and Career choice, indicating no statistically significant differences between the means of the different categories. However, the p-values for Transformation (0.011) and Development and training (0.023) measured below 0.05, indicating that the means of the different categories differed statistically significantly. The effect sizes showed medium to large effects for Transformation, where respondents who earned more than R40 000 (M = 3.44) per year were more positive about Transformation than all the other income categories (less than R10 000: M = 2.72, d = 0.72; R10 000–R20 000: M = 3.19, d = 0.72; R20 000– R40 000: M = 2.93, d = 0.33). Development and training showed medium effects, where respondents who earned more than R40 000 (M = 3.57) per year were more positive about Development and training than all the other income categories (less than R10 000: M = 2.95, d = 0.62; R10 000–R20 000: M = 3.27, d = 0.61; R20 000–R40 000: M = 3.03, d = 0.34). The Journal of the Southern African Institute of Mining and Metallurgy

Discussion A factor analysis was conducted on the scale items measuring women’s workplace experiences in the South African mining industry; five factors (Transformation, Female abuse, Personal care, Career choice, and Development and training) were extracted. Cronbach’s alpha coefficients were used to determine the internal reliability of the scale. Almost all values were above the required 0.70, indicating high reliability and internal consistency. The Cronbach’s alpha coefficient of Career choice measured 0.629 and the inter-item correlation 0.459, showing an acceptable reliability. The descriptive statistics showed that, on average, 60% of the respondents agreed with the statements contained in the Transformation (M = 3.11), Personal care (M = 3.18), and Development and training factors (M = 3.24), indicating that the majority of the respondents were satisfied with the way women were valued and embraced in the mining organizations, with the female protective equipment, clothing, and toilet facilities provided as well as with the Development and training opportunities offered for women. However, there is still much room for improvement in these areas to enhance women’s workplace experiences. The literature reviewed pointed out that women require adequate training and career development support (e.g. bursaries, study leave, and mentoring systems) (Jones and Moalusi, 2019; Matshingane, 2017; Mavuso, 2015; Slater, 2018) as well as provision for their personal needs (e.g. proper, hygienic ablution facilities and correctly fitting personal protective equipment) (Botha, 2017; James, 2018). Regarding Career choice (M = 2.52), only half of the respondents indicated that they worked at the mining organizations due to income advantages and not by free choice. The Female abuse factor (M = 3.07) showed an alarming response, as more than 60% of the respondents indicated that women are still subjected to harassment and abuse in the workplace. The literature reviewed confirmed that women who work at and in the mines, specifically underground, are often seen as sexual objects and are exposed to sexual harassment on a regular basis (Botha, 2016; Creamer Media, 2019; Jones and Moalusi, 2019; Minerals Council South Africa, 2019; Nene, 2016). A number of socio-demographic variables were used to measure their effect on the factors of women’s workplace experiences in the industry. These were tested using t-tests, ANOVAs, correlations, and effect sizes. A correlation test measured the linear association between age, highest qualification, level of employment, years working at the mine, income, and women’s workplace experiences in the South African mining industry. Small positive relationships were found between income and Transformation (p = 0.018, r = 0.214) as well as between income and Development and training (p = 0.028, r = 0.202), indicating that the higher the respondents’ income, the more positive they were about Transformation practices in the workplace as well as the Development and training opportunities offered. Small to moderate negative relationships were found between Transformation and Career choice (p = 0.030, r = –0.194) and Transformation and Female abuse (p = 0.000, r = –0.358) as well as Personal care and Career choice (p = 0.034, r = –0.189) and Personal care and Female abuse (p = 0.039, r = –0.183), indicating that the more positive respondents were about Transformation and Personal care in the workplace, the less they indicated that they are forced to work at the mines due to income advantages and the less they VOLUME 120

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An exploration of women’s workplace experiences in the South African mining industry felt that women are subjected to female abuse in the workplace. Medium to large positive relationships were found between Transformation and Personal care (p = 0.000, r = 0.486) as well as Transformation and Development and training (p = 0.000, r = 0.554), indicating that the more positive respondents were about Transformation in organizations, the more positive they felt about organizations addressing their personal, development and training needs. A moderate positive relationship was found between Personal care and Development and training (p = 0.001, r = 0.300), showing that the more positive respondents were about personal needs addressed, the more positive they felt about development and training needs met. The results of the t-tests indicated no effect between working in an open pit or deep mining (underground), affiliation to a union, race, and the five factors of women’s workplace experiences in the South African mining industry. The results showed a small effect for some of the factors. Not surprisingly, the data suggests that women working in an open pit are slightly more satisfied with Transformation and Personal care than those working in deep mining. The literature review confirmed limitations and deficiencies in terms of decent and hygienic toilet facilities underground (Botha, 2017, pp. 22, 24; Matshingane, 2017, p. 5; MHSC, 2015, p. 64; Minerals Council South Africa, 2019, p. 3). The data also showed that women affiliated to a union were less satisfied with Transformation, Personal care, and Development and training than those not affiliated. In general, employees belong to trade unions to represent their interests and to negotiate working conditions and rewards with employers (Watson, 2017, p. 354). It can therefore be deduced that the respondents who joined a trade union did so based on their dissatisfaction with their working conditions. The data also showed that black respondents agreed more than ‘other racial groups’ that Female abuse is a problem in the workplace. From the biographical information it is evident that 83.9% of the respondents were black, and this could explain this result. The results of the ANOVA indicated no statistically significant differences between the means of the demographic groups’ mining sector, age, and years working in the mining industry and the five factors of women’s workplace experiences. The results of the effect sizes showed a small effect for some of the factors, as indicated in the ‘Empirical results’ section. Furthermore, the ANOVA indicated few significant differences between the means of the demographic groups’ place of work, highest qualification, level of employment, income, and some of the factors of women’s workplace experiences; the effects ranging from small to large. Statistically significant differences were found between the means of the workplace categories for Transformation and Personal care, the highest qualification categories for Female abuse, the level of employment categories for Career choice, and income categories for Transformation and Development and training. Respondents who worked underground as well as both underground and on the surface were less positive about Transformation and Personal care than those who worked on the surface and in other work areas. Respondents with a matric or lower qualification agreed less than all the other qualification categories that women are subjected to Female abuse in the workplace. Respondents employed at senior management level disagreed the most with the statements contained in the Career choice factor, indicating that they worked at the mine due to free choice, and not because the income was good. Respondents who earned more than

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R40 000 per year were more positive about Transformation and Development and training than all the other income categories.

Conclusion and recommendations The primary purpose of this study was to explore women’s current workplace experiences in the South African mining industry. From the results it is evident that progress has been made in some instances, but in other areas deficiencies are still present. It is imperative that mining organizations attend to the challenges confronting women to enhance their workplace experiences, to ensure successful integration of women in the South African mining industry, and to consequently contribute to effective transformation of the industry. The following recommendations are informed by the literature review and the empirical results. ➤

Female abuse should not be tolerated and should be eradicated. Improved implementation and operationalization of sexual harassment policies are required to counter sexual harassment practices. ➤ Adequate and hygienic toilet facilities underground should be provided to improve women’s working conditions. ➤ Ongoing research should be conducted by mining houses, mining organizations, academic bodies, and other interested parties to determine barriers to, and progress in, women’s working conditions and workplace experiences.

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Benhaus – a landmark decision, one less hoop for contract miners but a clarion call for an overhaul of the South African mining regime K. Thambi1 Affiliation: 1 School of Law, University of Witwatersrand, South Africa. Correspondence to: K. Thambi

Email:

kiyasha.thambi@wits.ac.za

Dates:

Received: 25 Nov. 2019 Revised: 21 Jul. 2020 Accepted: 19 Aug. 2020 Published: August 2020

How to cite:

Thambi, K. Benhaus – a landmark decision, one less hoop for contract miners but a clarion call for an overhaul of the South African mining regime. The Southern African Institute of Mining and Metallurgy

Synopsis The mining industry has evolved, such that the means of production that were once in the hands of major players or power houses have become equally accessible to smaller entrants, i.e. junior mining companies and contract miners. Contract mining involves contractual relationships between mine owners or mineral right holders and third parties to conduct mining activities on behalf of the right holders. The current mining income tax legislation has been a considerable obstacle to contract miners. Under its terms, they have been viewed as mining on behalf of third-party mineral rights holders. As such, expenditure incurred in relation to contract mining activities was often disallowed by the South African Revenue Service (SARS). However, the recent judgement of the Supreme Court of Appeal, Benhaus Mining (Pty) Ltd v CSARS 2020 (3) SA 325 (SCA) (Benhaus), rightfully or wrongfully, appears to provide clarity regarding the fate of contract miners’ involvement in the mining value chain. The taxpayer, a contract miner, was held to be conducting mining operations within the meaning of S15(a) read with s1 of the Income Tax Act 58 of 1962 (the Income Tax Act). This paper looks at how contract mining has traversed the mining tax landscape, the implications of the Benhaus judgment, and stresses the necessity for clear policy reform to the mining tax regime and equally to legislation framed to give effect to these policies. Keywords Contract mining, owner mining, tax, DMRE, mining regime reforms.

DOI ID: http://dx.doi.org/10.17159/24119717/1031/2020 ORCiD ID: K. Thambi https://orchid.org/0000-00034456-3027

Introduction The mining industry’s’ evolution is punctuated by factors such as legislative amendments to the Income Tax Act 58 of 1962 (the Income Tax Act), the Mineral and Petroleum Resources Development Act 28 of 2002 (MPRDA), the Broad-Based Socio-Economic Empowerment Charter for the Mining and Minerals Industry 2018 (the Mining Charter), and the Customs and Excise Act, 91 of 1964 (the Customs Act), not to mention ancillary factors such as restrictions of changes in ore grades, technological advances, national and international standards. Mining is a major contributor to South Africa’s economy, directly and indirectly, through job creation and the sustainable development of the communities within which mining companies operate (among others). However, the establishment of a mine involves high startup capital and infrastructure costs, and the assumption of excessive risks with long lead times before any profits are reaped; and these factors have a major impact on the cash-flow implications for a newly established mine. In recognition of these factors and in a bid to encourage mining, from the aspects of both investment and job creation, government incentivized the mining industry. These incentives took the form of tax incentives (among others), namely the deduction of capital expenditure incurred for a mining operation (Redemption Allowance) (Tickle, Ajam, and Padia, 2016). In spite of the intent behind these tax incentives, it is apparent that at the time of conceptualizing and drafting these provisions, factors such as ‘contract mining’ were not on the horizon. Furthermore, there have been no efforts at establishing an alignment and/or synergy between the mining income tax regime and South Africa’s highly evolved mining industry practices. Thus for most parts both have at times often been incompatible. Current mining income tax legislation and its implementation posed insurmountable burdens for miners and contract miners alike. In terms of the current legislation, contract miners are categorized as mining on behalf of third-party mineral rights holders. As such,

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Benhaus – a landmark decision, one less hoop for contract miners expenditure incurred during their contract mining activities has been disallowed by the South African Revenue Service (SARS). SARS’ reasoning for this was that the core element of mining is the generation of income from the sale of minerals and that, unless a person is engaged in such sale, that person is not carrying on mining operations. By implication, contract miners were seen as not engaged in mining operations but mere service providers to persons who are mining (Tickle, Ajam, and Padia, 2016). The contentious issue between SARS and Benhaus Mining (Pty) Ltd (Benhaus) was essentially whether income derived by a company that, in terms of a contract with another company, excavates and removes topsoil, blasts rock, extracts, crushes, and screens the chrome-bearing ore, and delivers it, for a predetermined fee, to that other company which mills, washes, and smelts the concentrate to produce ferrochrome is ‘derived … from mining operations’ in terms of section 15 read with section 36(7C) (Income Tax Act). Benhaus had extracted and delivered mineral-bearing ore on behalf of the mining rights holder for a predetermined fee. Despite having several contracts with other mines, it included the income earned from these mines as a global amount. Even though Benhaus acknowledged that it did not conduct the full spectrum of the chrome mining process, it proceeded to claim the related deductions in respect of its extraction and deliveries in its income tax returns. In claiming such deductions, it relied on the basis that it was conducting mining operations as defined in the Income Tax Act. In terms of the judgement handed down by the Supreme Court of Appeal, the taxpayer, Benhaus, a contract miner, was held to be conducting mining operations within the meaning of s15(a) read with s1 of the Income Tax Act. While the case sheds some light regarding the place of contract miners within the mining value stream for income tax purposes, it focuses attention on the need to address longstanding inefficiencies and incongruence in the mining regime as a whole. There has been a definite lack of alignment between various departments, policy considerations, and processes, a lack of appreciation of the operational issues between mining right holders and contractors alike. This inadvertent disjuncture, is the ‘elephant in the room’.

The problem The fate of contract mining hinges on whether the interpretative process in the Benhaus judgement of the current legislation is an exact one. If so, then there are aspects of the ‘mining’ regime, that require policy reviews/intervention and alignment to current industry practice, failing which there are may be unintended consequences against the backdrop of this judgment. The problem is multifaceted. Firstly, mining tax legislation was not initially designed to provide for contract mining. SARS has long relied on policy considerations that are in the current mining climate. The definitions of ‘mining operations’ and ‘mining’ are broad, and the requirement that minerals be ‘won’ is counterintuitive to these definitions; limiting the winning of a mineral to a single taxpayer. Secondly, mining is limited to persons who ‘hold’ mining rights in terms of the MPRDA. Thirdly, this is exacerbated by the fact that contractual arrangements between holders of mineral rights and contract miners remain unregulated. Finally, there is no synergy between the diverse legislation (and regulations) that impacts the mining industry.

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Brief background to contract mining Today, mining operations include both internal and subcontracted functions. While larger companies whose core business is mining prefer that their operations be controlled and managed by the owner’s team junior mining companies rely on contract miners as they often lack sufficient experience to carry out mining operations. Where joint ventures are involved, the default seems to be the utilization of contractors as a bargaining chip or ‘deal sweetener’ for both parties. (Keel, 2018; Rupprecht, 2015). Ultimately, it boils down to ‘control’. Although in most cases control normally vests with the party owning or leasing the mining equipment, it is the control of the actual mining process which determines whether an operation is owner mined or contract mined. However, the decision between owner mining and contract mining remains a corporate one, taken in conjunction with project-specific issues such as life of mine, mining rate and variability of the mining rate, availability and experience of personnel, project management issues, and financial limitations (Rupprecht, 2015). Starting a new mine in a remote area poses challenges to mining companies, as the local available labour pool does not have the necessary skills to operate large specialized equipment. In such scenarios contract mining allows for the prompt deployment of modern equipment and a skilled workforce, while providing cost efficiencies and effective performance management systems, and still securing attractive commercial terms for additional capital equipment requirements. In other words, it provides owners with some advantages, i.e. economies of scale and scope through access to capital equipment and human resources; optimized mining, plant, and equipment utilization rates and labour productivity; and minimization of the owner’s capital exposure. This allows the company to better utilize capital and better equip (or re-equip) mines with restricted capital budget. (Keel, 2018; Rupprecht, 2015). The downside to the use of contractors is that the owner does not have direct control over mining activities or health and safety issues (Rupprecht, 2015). This is exacerbated by their inability to access capital needed to procure equipment, which has a knock-on effect on other core business, turnaround time, and changes in the pace and nature of mining operations (van Wyngaardt, 2013). Another downside is the uncertainty of unregulated contract mining arrangements, as to who is engaged in mining and therefore whether the owner of the mining right or the contract miner could claim the relevant tax allowances (Tickle, Ajam, and Padia, 2016). Nevertheless, in practice there are various permutations to contract mining. Often the contractor undertakes mining operations for the benefit of another, and receives no share in the resultant profits other than a negotiated fee related effort and costs. Sometimes, especially in the case of opencast mining, the owner of a mine or mine ‘owner’ subcontracts all or a portion of the mining operations to a third party. Typically, the contracting arrangement requires a third party or contract miner to use earthmoving equipment to win ore by opencast mining methods and transport the ore to a processing plant. Evidently, when applying these scenarios to tax incentives as per the current mining income tax, the results indicated that the contractor was clearly ‘conducting a process by which a mineral is won from the earth’; thus the income that he derived ought to be taxed in accordance with mining tax rates and the expenditures deductible The Journal of the Southern African Institute of Mining and Metallurgy

Benhaus – a landmark decision, one less hoop for contract miners in accordance with the special mining tax provisions. Of course, to the extent that the contractor does not undertake the mining operations but merely rents or leases capital equipment to a party who does undertake such operations, the contractor is not undertaking mining operations. In Gloucester Manganese Mines (Postmasburg) Ltd v Commissioner for Inland Revenue 1943 TPD 232 (12 SATC 229) (a case relied on by the litigant Benhaus), the taxpayer granted the sole right to mine manganese on a certain property to a third party, in return for a lease charge of 25% of the net profits. It was held that the lessee was carrying on mining operations. In fact, since the lease did not constitute a partnership, the lessee was the only party carrying on such operations. Despite courts justifying the disallowance of capital expenditure incurred by contract miners based on the latter’s degree of ‘risk-taking’, contract miners do engage in various levels of risk. There are several risks in mining regardless of who does the actual mining. The mine owner bears the risks of geological modelling, grade control, mine design, geotechnical stability, environmental and community issues, and the instability of the market price for the end product (Kirk, 2002). However, when evaluating contract and owner mining, the main comparative risk areas are equipment selection and matching, equipment performance (productivity, availability, and utilization), quality and control of the ore, health and safety, human resources management, contractual and litigation issues, and production or operating costs (Suglo, 2009). Not to mention the fact that contracting companies have traditionally followed a very specific remuneration and benefit model so as to operate at a lower cost base and to remain profitable.

Context to the Benhaus judgment Prior to the Benhaus judgment, the Tax Court had dealt with the issue regarding contract mining and the redemption allowance in two cases. The Tax Court, in ITC 1913 (supra) and ITC 1907 80 SATC 271 (Classic Challenge Trading (Pty) Ltd), vigorously justified a finding that the core element of mining is the generation of income from the sale of minerals and that, unless a person is engaged in the sale of the minerals, that person is not carrying on mining operations. In both instances, the findings had been that the contract miner was a service provider to the person or persons who were mining and therefore not engaged in mining operations. Following these two earlier judgments of the Tax Court regarding the applicability of the Redemption Allowance to contract miners, Benhaus articulated something very different. The court a quo found stated that Benhaus was not engaged in mining within the meaning of sections 1 and 15(a) of the Income Tax Act and was therefore not entitled to deduct the capital expenditure in respect of the equipment it used for the extraction of mineral-bearing ore from the ground as it did not derive its income from mining operations. The activities undertaken by Benhaus on behalf of its clients were as follows per paragraphs [11] and [12] of the judgment of Lewis ADP: ‘ [11] The services that Benhaus rendered included establishing sites for open cast mining, and fencing them off; constructing workshops; constructing and maintaining The Journal of the Southern African Institute of Mining and Metallurgy

access roads, and primary and secondary haul roads; removing topsoil and stockpiling it in designated areas; excavating and stockpiling material extracted from the ground; removing waste; constructing storm water drainage; blasting mineral-bearing ore; delivering the ore to the client’s premises for processing; and rehabilitating the mining area after extraction. [12] The essence of the contracts between Benhaus and its clients was to extract the mineral bearing ore (the mineral being chrome) on behalf of the client in return for a fee calculated at a rate per ton of chrome-bearing ore that was delivered to the client’s processing plant…’ (Benhaus, 2019). Benhaus claimed the deduction of capital development expenditure in terms of section 15 of the Income Tax Act. In disallowing this claim, the crux of SARS’ reasoning was that mining is a risky business in which the return on investment is unpredictable and that policy considerations indicate that Benhaus should not be entitled to claim mining incentives. It went on to say that the mining allowances were designed to incentivize mining development; and since contract miners earned returns upon commencement of mining operations they had thus not carried any risk therein. Despite SARS’ reliance on policy considerations, including the 2016 Davis Committee Report, Lewis ADP found that the court was not concerned with policy but with interpreting the law in light of the facts (Benhaus, 2019). Lewis ADP focused on two primary issues, which had been central to the judgment of Sutherland J in ITC 1907. The first issue was the proposition that a person could only be conducting mining operations if they bore the risk inherent in the operation. To which Lewis ADP (at paragraph [27]) acknowledged that this may have been the case in the precedent that had been relied upon by Sutherland J; however, she added that it was not evident as to why the question whether an entity is conducting mining operations is dependent on the miner bearing risk (Benhaus, 2019). The second issue at paragraph [29] of the judgment was that it is inconceivable that any part of the process of winning minerals from the earth could constitute mining operations. The definition of mining and mining operations refers to a process ‘by which any mineral is won from the soil or from any substance or constituent thereof’. This could be construed in such a way that both the entity that dug the mineral-bearing ore from the earth and the entity that operated the process of separating the mineral from the ore or rock would be involved in mining the same mineral. That construction, she held, was incorrect (Benhaus, 2019). On appeal, the main question was therefore whether the first stage of the chrome mining process constituted mining under the Income Tax Act, i.e. whether Benhaus conducted mining or mining operations (Benhaus, 2020). The court gave due consideration to the clear meaning of the term ‘mining operations’, and the approach adopted in Western Platinum Ltd v CSARS, i.e. properly construed, the definition of mining or mining operations, referred to a taxpayer conducting the business of extracting minerals from the soil. The question confronting the SCA was in essence a question regarding the correct interpretation of the Income Tax Act. Some scholars argue that the SCA digressed in applying a literal VOLUME 120

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Benhaus – a landmark decision, one less hoop for contract miners approach to the definition in section 1 of the Income Tax Act as to whether Benhaus was conducting mining operations. Nevertheless, what is pivotal is Mocumie JA’s argument in the concurring judgement. She called for the necessity to amend the Income Tax Act. Failing to do so, she added, would merely exacerbate the void between the meaning of mining operations in the Income Tax Act and its corollary of accelerated tax deductions, resulting in a class of unintended beneficiaries, to the detriment of the fiscus.

Aspects of the ’mining’ regime, that require policy reviews and alignment to current industry practice The Benhaus judgement may address but one aspect of the mining regime, wherein the contract miner is a ‘player’. In executing their mandates, contract miners may be confronted with additional variables geared for mining right holders and vice versa (over and above the Income Tax Act, already discussed above per Benhaus et al.), i.e. the MPRDA, the Mining Charter, and the Customs Act (among others).

Income Tax Act 58 of 1962 In terms of the Income Tax Act, taxpayers engaged in mining operations are provided with a special dispensation. This special dispensation entails the application of specific rules to the deduction of prospecting expenses and capital expenditure incurred in engaging in mining operations. The Tax Act defines mining operations and mining as including: ‘every method or process by which any mineral (including natural oil) is won from the soil or from any substance or constituent thereof’. ‘Mining’ and ‘mining operations’ seemingly include the extraction of mineral-bearing ore and the extraction of the mineral or minerals contained therein. Notably, the use of the word ‘include’ in the definition was meant to indicate that the meaning is not intended to be an exhaustive guide. Furthermore, the application of the relevant sections allowing a deduction for capital expenditure relies on the term ‘mineral’. Despite the fact that the term ’mineral’ is of great significance in the overall definition, for income tax purposes, of mining operations and mining, the term is not defined in s1. However, the term ‘mining operations’ has a somewhat different meaning in terms of s15(a), which incorporates more than merely excavating and extracting mineral-bearing ore. Nevertheless, the provisions of s15(a) of the ITA, read with s36(7C), in light of the definition of ‘mining operations or mining’ in s1, provide the mechanism and requirements for the deduction of capital expenditure incurred for a mining operation (Redemption Allowance). Section 15 of the ITA provides that a deduction shall be allowed as per s36, in lieu of an ordinary deduction under s11. Section 36 in turn provides for deduction of any capital expenditure from income derived from ‘working’ any producing mine. The standard deductions relating to capital expenditure require amortization of the expenditure over the useful life of the asset. The effect of these provisions means that a taxpayer engaged in mining operations on a producing mine will be entitled to fully deduct related capital expenditure in the year of assessment it was incurred. However, the core element of mining is the generation of income from the sale of minerals. Therefore, unless a person was so engaged, that person was not carrying on mining operations (van Blerck, 1992; Tax Act, 1962).

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Mineral and Petroleum Resources Development Act 28 of 2002 (MPRDA) The provisions contained in the MPRDA, which is the principal law governing/regulating the mining industry, affirms the need for the establishment of a nexus between a mining right and mining activity. This approach aligns with the mandate of the MPRDA, i.e. equitable access to and sustainable development of the country’s’ mineral resources, and related matters. Furthermore, section 5A of the MPRDA provides that ‘[n] o person may... mine... or commence with any work incidental thereto on any area without... a... mining right’. It limits mining to persons who ‘hold’ mining rights in terms of the Act. The MPRDA, being a gatekeeper, is a means of securing accountability by the rights holder to ensure compliance with requirements associated with the mining rights. It is also a means at ensuring that the intended beneficiaries of the rights (the mining rights holder) do not subvert their rights contractually to someone else (Tickle, Ajam, and Padia, 2016). Section 38 of the MPRDA provides that holders of permits or rights in terms of the MPRDA must give effect to the objectives of integrated environmental management laid down in Chapter 5 of NEMA. As such, it is effectively the mining right holder’s obligation to make financial provision for the rehabilitation or management of negative environmental impacts before approval of its Environmental Management Plan (EMP). Equally, the mining right holder has to maintain financial provision until receipt of a closure certificate. Lastly, section 37A of the Income Tax Act attempts to connect the aforementioned regulation regarding mining rehabilitation with tax policy, by establishing a mining rehabilitation fund. This section applies strict rules and allows a tax deduction for cash payments made to a dedicated mining rehabilitation fund. To the extent that there has been a contravention of Section 37A, Section 37A (8) is a catch-all provision that ensures that the rehabilitation fund and mining company pay tax where it is triggered.

The Broad-Based Socio-Economic Empowerment Charter for the Mining and Minerals Industry, 2018 (Mining Charter) The Mining Charter came into force on 1 March 2019. The Guidelines do not address ambiguities created by the Charter. What is more, they contain provisions that give reason for alarm: to name but one, ‘the absence of provisions for the amendment of existing mining rights; and the Minister’s seemingly unlimited ability to review and revise the obligations imposed under the Charter from time to time’ (Leon, 2019). However, interestingly, the Mining Charter 2018 does recognize contract miners/mining in paragraph 5.7… ‘ 5.7 Contractors and inclusive procurement 5.7.1 Where a mining right holder uses a contractor to undertake extraction and/or processing (crushing and concentration) of minerals on their behalf, any mining goods and services used by the contractor will be deemed to have been used by the right holder. 5.7.2 The mining right holder will therefore be expected to report on the procurement element using procurement spend data from their contractor’ (Mining Charter, 2018). The Journal of the Southern African Institute of Mining and Metallurgy

Benhaus – a landmark decision, one less hoop for contract miners These are factors that can easily be incorporated in the contract mining arrangements.

The Customs and Excise Act, 91 of 1964 (Diesel Rebates) The Tax Court had to determine, in a recent decision, which activities qualify as ‘primary production activities in mining’ as required by note 6(f) of Schedule 6, part 3 of the Customs and Excise Act, for a taxpayer to qualify for the specific diesel rebates. The court determined that the rebate in question was available to taxpayers in the business of mining. It added that this ensured that these businesses could be internationally competitive. As such the term ‘mining’ was interpreted accordingly. The court went on to interpret the term mining to include ‘the process or business of digging in mines to obtain minerals’ (Glencore Operations SA (Pty) Limited v The Commissioner for the South African Revenue Service unreported case no 11696/18 of 24 October 2019 para 30 and 35).

they align with global and national strategies. Furthermore, as Rupprecht (2015) suggests, in future, owners must fully understand when to use contract mining and when to pursue owner mining. Until the mining regime has been given a complete overhaul, it is important that owners fully understand the technical and economic ramifications of engaging in contract mining (per the Benhaus case), while ensuring that they have a handle on their contract management systems. If the mining sector is to truly become the ‘sunrise industry’ that the government wishes it to be, it will have to become more proficient in how it regulates the industry (Leon, 2019). Current policy initiatives do not sufficiently address the fragmentations facing the mining industry, nor do they support developmental linkages, to sustain this sector – a sector that hovers between policy and politics.

References

The way forward

Benhaus Mining v CSARS (165/2018) [2019] ZASCA.

No doubt, Benhaus is a landmark case. In retrospect, the case deals with the salient issues affecting contract mining. It ameliorates the impact that the current mining income tax regime has had on contract miners. This includes measures to try to fit contract mining into a somewhat discombobulated framework, never designed with contract mining in mind. However, this case signals the need for the DMRE, in consultation with the various stakeholders, to review current policy considerations relating to mining as a whole. The start, as per scholars, including the Davis Committee, is the recommendation for the sorely needed amendment of the Income Tax Act, as well as the establishment of clear policies for the taxation of mining income; in equal measure to legislation framed to give effect to these policies, and aligning the mining regime to industry norms. Secondly, research into policy considerations that seek to consider South Africa’s National Development Plans in resuscitating the mining sector. These are changes one can hope to see in the near future (Tickle, Ajam, and Padia, 2016).

Benhaus Mining v CSARS [2019] ZASCA 17..

In the interim Pending the aforementioned overhaul of the mining income tax and mining regimes, due consideration should be given to the ideologies of ‘agency-principal’ in relation to contract miners and mining right holders. To facilitate this concept, the Davis Tax Committee recommended the setting up of a comprehensive guide containing the terms under which the agent and principal would operate. The Treasury, working with SARS, could also provide guidance by ameliorating the practical implication of the findings in this judgment. Furthermore, the issue around unregulated contract mining arrangements could be addressed by requiring the lodging of respective contracts at the DMRE; as addendums to new and/ or existing mining right holders permits. This would ensure the establishment of accountability as well as compliance with the aforementioned legislation, and enable the regulator (DMRE) to retain control of the mining processes, and possibly intercede or adjudicate such contract terms where necessary.

Conclusion In terms of the Mining Charter 2018, South African mines have to drastically change their operating model and ensure that The Journal of the Southern African Institute of Mining and Metallurgy

Benhaus Mining (Pty) Ltd v CSARS 2020 (3) SA 325 (SCA). Keel, N. 2018. Contract mining: The good, the bad and the ugly. Mining News, 11 September 2018. https://www.mining.com/web/contract-mining-good-badugly/ [accessed 7 August 2019]. Leon, P. 2019. Mining Charter III: Certainty, but at a cost. BizNews, 12 March 2019. https://www.biznews.com/briefs/2019/03/12/mining-charter-peter-leon [accessed 19 August 2019] Le Roux, L. 2019. Mining – the SCA takes a pragmatic stance. Synopsis Tax Today, March 2019. https://www.pwc.co.za/en/assets/pdf/synopsis/synopsismarch-2019.pdf [Accessed 7 August 2019] Maphatsoe, K. 2019. Mining Charter sets tone for mining suppliers and service providers. Mining Weekly, 15 March 2019 [accessed 7 August 2019]. Mukumba, T. and Louw, H. 2019. A groundbreaking victory for contract miners, won from the soil. Tax & Exchange Control Alert, 12 April 2019. https:// www.cliffedekkerhofmeyr.com/en/news/publications/2019/Tax/tax-alert-12april-A-groundbreaking-victory-for-contract-miners-won-from-the-soil-.html [Accessed 7 August 2019]. Department of Mineral Resources. 2018. Implementation Guidelines for Broad Based Socioeconomic Empowerment Charter for the Mining and Minerals Industry 2018. Government Gazette, no. 42122. 19 December 2018. Rupprecht, S.M. 2015. Owner versus contract miner — a South African update. Journal of the Southern African Institute of Mining and Metallurgy, vol. 115, no.11. pp.1022–1025. South Africa. 2002. Mineral and Petroleum Resources Development Act 2002. Government Gazette, vol. 448. pp. 5-122. South Africa. 1962. Income Tax Act, 58 of 1962. Section 36. Suglo, R.S. 2009. Contract mining versus owner mining – The way forward. Ghana Mining Journal, vol. 11. pp. 61–68. Tickle, D., Ajam, T., and Padia, N. 2016. Davis Tax Committee. Second and Final Report on Hard-Rock Mining. https://www.taxcom.org.za/docs/20171113%20 Second%20and%20final%20hard-rock%20mining%20report%20on%20 website.pdf Van Blerck, M.C. 1992. Mining Tax in South Africa (1990). TAXFAX. Van Wyngaardt, M. 2013. Contract to distinguish owner mined from contract mined operations. Mining Weekly, 24 May 2013. https://m.miningweekly. com/article/contract-to-distinguish-owner-mined-from-contract-minedoperations-2013-05-24 [accessed 7 August 2019]. VOLUME 120

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Company affiliates The following organizations have been admitted to the Institute as Company Affiliates 3M South Africa (Pty) Limited

Ex Mente Technologies (Pty) Ltd

AECOM SA (Pty) Ltd

Expectra 2004 (Pty) Ltd

AEL Mining Services Limited

Exxaro Coal (Pty) Ltd

African Pegmatite (Pty) Ltd

Exxaro Resources Limited

Air Liquide (Pty) Ltd

Filtaquip (Pty) Ltd

Alexander Proudfoot Africa (Pty) Ltd

FLSmidth Minerals (Pty) Ltd

AMEC Foster Wheeler

Fluor Daniel SA ( Pty) Ltd

AMIRA International Africa (Pty) Ltd

Franki Africa (Pty) Ltd-JHB

An Delkor(Pty) Ltd

Fraser Alexander (Pty) Ltd

Anglo Operations Proprietary Limited

G H H Mining Machines (Pty) Ltd

Anglogold Ashanti Ltd

Geobrugg Southern Africa (Pty) Ltd

Arcus Gibb (Pty) Ltd

Glencore

ASPASA

Hall Core Drilling (Pty) Ltd

Atlas Copco Holdings South Africa (Pty) Limited

Hatch (Pty) Ltd

Aurecon South Africa (Pty) Ltd Aveng Engineering Aveng Mining Shafts and Underground Axiom Chemlab Supplies (Pty) Ltd Axis House Pty Ltd Bafokeng Rasimone Platinum Mine Barloworld Equipment -Mining BASF Holdings SA (Pty) Ltd BCL Limited Becker Mining (Pty) Ltd BedRock Mining Support (Pty) Ltd BHP Billiton Energy Coal SA Ltd

MSA Group (Pty) Ltd Multotec (Pty) Ltd Murray and Roberts Cementation

Bluhm Burton Engineering (Pty) Ltd Bond Equipment (Pty) Ltd

Ncamiso Trading (Pty) Ltd New Concept Mining (Pty) Limited Northam Platinum Ltd - Zondereinde Opermin Operational Excellence Optron (Pty) Ltd Paterson & Cooke Consulting Engineers (Pty) Ltd Polysius a Division of Thyssenkrupp Industrial Sol

Immersive Technologies

Precious Metals Refiners

IMS Engineering (Pty) Ltd

Ramika Projects (Pty) Ltd

Ingwenya Mineral Processing (Pty) Ltd

Rand Refinery Limited

Ivanhoe Mines SA

Redpath Mining (South Africa) (Pty) Ltd

Joy Global Inc.(Africa)

Rocbolt Technologies

Kudumane Manganese Resources

Rosond (Pty) Ltd

Leco Africa (Pty) Limited

Royal Bafokeng Platinum

Leica Geosystems (Pty) Ltd

Roytec Global (Pty) Ltd

Longyear South Africa (Pty) Ltd

RungePincockMinarco Limited

Lull Storm Trading (Pty) Ltd

Rustenburg Platinum Mines Limited Salene Mining (Pty) Ltd Sandvik Mining and Construction Delmas (Pty) Ltd

Magnetech (Pty) Ltd Magotteaux (Pty) Ltd Maptek (Pty) Ltd

CDM Group

Namakwa Sands(Pty) Ltd

HPE Hydro Power Equipment (Pty) Ltd

Malvern Panalytical (Pty) Ltd

Bouygues Travaux Publics

Nalco Africa (Pty) Ltd

Perkinelmer

Herrenknecht AG

Maccaferri SA (Pty) Ltd

Blue Cube Systems (Pty) Ltd

Modular Mining Systems Africa (Pty) Ltd

Sandvik Mining and Construction RSA(Pty) Ltd SANIRE

Maxam Dantex (Pty) Ltd

Schauenburg (Pty) Ltd

MBE Minerals SA Pty Ltd

Sebilo Resources (Pty) Ltd

MCC Contracts (Pty) Ltd

SENET (Pty) Ltd

MD Mineral Technologies SA (Pty) Ltd

Senmin International (Pty) Ltd

MDM Technical Africa (Pty) Ltd

Smec South Africa

Metalock Engineering RSA (Pty)Ltd

Sound Mining Solution (Pty) Ltd

Metorex Limited

SRK Consulting SA (Pty) Ltd

CSIR Natural Resources and the Environment (NRE)

Metso Minerals (South Africa) Pty Ltd

Time Mining and Processing (Pty) Ltd

Micromine Africa (Pty) Ltd

Timrite Pty Ltd

Data Mine SA

MineARC South Africa (Pty) Ltd

Tomra (Pty) Ltd

Digby Wells and Associates

Minerals Council of South Africa

Ukwazi Mining Solutions (Pty) Ltd

DRA Mineral Projects (Pty) Ltd

Minerals Operations Executive (Pty) Ltd

Umgeni Water

DTP Mining - Bouygues Construction

MineRP Holding (Pty) Ltd

Webber Wentzel

Duraset

Mintek

Weir Minerals Africa

Elbroc Mining Products (Pty) Ltd

MIP Process Technologies (Pty) Limited

Welding Alloys South Africa

eThekwini Municipality

MLB Investment CC

Worley

CGG Services SA Coalmin Process Technologies CC Concor Opencast Mining Concor Technicrete Council for Geoscience Library CRONIMET Mining Processing SA (Pty) Ltd

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NATIONAL & INTERNATIONAL ACTIVITIES 2021 18–22 April 2021 — IMPC2020 XXX International Mineral Processing Congress Cape Town, South Africa Contact: Camielah Jardine Tel: +27 11 834-1273/7 Fax: +27 11 838-5923/833-8156 E-mail: camielah@saimm.co.za Website: http://www.saimm.co.za 9–11 June 2021 — Diamonds – Source To Use — 2021 Conference ‘Innovation And Technology’ The Birchwood Hotel & OR Tambo Conference Centre, Johannesburg Contact: Camielah Jardine Tel: +27 11 834-1273/7 Fax: +27 11 838-5923/833-8156 E-mail: camielah@saimm.co.za Website: http://www.saimm.co.za 13–16 July 2021 — Copper Cobalt Africa Incorporating The 10th Southern African Base Metals Conference Avani Victoria Falls Resort, Livingstone, Zambia Contact: Camielah Jardine Tel: +27 11 834-1273/7 Fax: +27 11 838-5923/833-8156 E-mail: camielah@saimm.co.za Website: http://www.saimm.co.za 29–30 July 2021 — 5th Mineral Project Valuation Colloquium Glenhove Events Hub, Melrose Estate, Johannesburg Contact: Gugu Charlie Tel: +27 11 834-1273/7 Fax: +27 11 838-5923/833-8156 E-mail: gugu@saimm.co.za Website: http://www.saimm.co.za 16–17 August 2021 — Worldgold Conference 2021 Misty Hills Conference Centre, Muldersdrift, Johannesburg, South Africa Contact: Camielah Jardine Tel: +27 11 834-1273/7 Fax: +27 11 838-5923/833-8156 E-mail: camielah@saimm.co.za Website: http://www.saimm.co.za 29 August–2 September 2021 — APCOM 2021 Minerals Industry Conference ‘The next digital transformation in mining’ Misty Hills Conference Centre, Muldersdrift, Johannesburg, South Africa Contact: Camielah Jardine Tel: +27 11 834-1273/7 Fax: +27 11 838-5923/833-8156 E-mail: camielah@saimm.co.za Website: http://www.saimm.co.za

Tel: +27 11 834-1273/7 Fax: +27 11 838-5923/833-8156 E-mail: camielah@saimm.co.za Website: http://www.saimm.co.za 27–30 September 2021 — 8th Sulphur and Sulphuric Acid Conference 2021 The Vineyard Hotel, Newlands, Cape Town, South Africa Contact: Camielah Jardine Tel: +27 11 834-1273/7 Fax: +27 11 838-5923/833-8156 E-mail: camielah@saimm.co.za Website: http://www.saimm.co.za 4–6 October 2021 — 8th International PGM Conference 2021 ‘PGMs – Enabling a cleaner world’ South Africa Contact: Camielah Jardine Tel: +27 11 834-1273/7 Fax: +27 11 838-5923/833-8156 E-mail: camielah@saimm.co.za Website: http://www.saimm.co.za 18–20 October 2021 — South African Rare Earths International Conference 2021 ‘Driving the future of high-tech industries’ Swakopmund Hotel And Entertainment Centre, Swakopmund, Namibia Contact: Camielah Jardine Tel: +27 11 834-1273/7 Fax: +27 11 838-5923/833-8156 E-mail: camielah@saimm.co.za Website: http://www.saimm.co.za 26–27 October 2021 — SAMCODES Conference 2021 ‘Good Practice and Lessons Learnt’ Industry Reporting Standards Glenhove Events Hub, Melrose Estate, Johannesburg, South Africa Contact: Camielah Jardine Tel: +27 11 834-1273/7 Fax: +27 11 838-5923/833-8156 E-mail: camielah@saimm.co.za Website: http://www.saimm.co.za 9–11 December 2021— Massmin 2020 Eight International Conference & Exhibition on Mass Mining Virtual Conference 2020 Santiago, Chile, Contact: J.O. Gutiérrez Tel: (56-2) 2978 4476 Website: www.massmin2020.com

2022 17–24 June 2022 — NAT2020 North American Tunneling Conference Philadelphia Website: http://www.natconference.com

21–22 September 2021 — 5th Young Professionals Conference 2021 ‘A Showcase of Emerging Research and Innovation in the Minerals Industry’ The Canvas, Riversands, Fourways, South Africa Contact: Camielah Jardine

Owing to the current COVID-19 pandemic our 2020 conferences have been postponed until further notice. We will confirm new dates in due course.

SAIMM ONLINE CONFERENCE

THE UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG, MINTEK AND THE SOUTHERN AFRICAN INSTITUTE OF MINING AND METALLURGY ARE HOSTING A CONFERENCE ON:

MINE-IMPACTED WATER

FROM WASTE TO RESOURCE FROM RESEARCH TO IMPLEMENTATION: CONSIDERING MINE-IMPACTED WATER AS A RESOURCE

FREE ONLINE CONFERENCE

ABOUT THE ONLINE CONFERENCE

The University of the Witwatersrand through the DSI/NRF SARChI research chair in Hydrometallurgy and Sustainable Development in collaboration with Mintek and the Southern African Institute of Mining and Metallurgy (SAIMM) will be hosting a conference on mine-impacted water including acid mine drainage (AMD). With a theme of “From research to implementation: considering mine-impacted water as a resource”, the conference which will run over a period of three weeks in the month of November this year, will provide excellent opportunities for industry, researchers and other stakeholders from across the globe to share unbiased expertise and advocacy with respect to the legacy and sustainable solutions related to mining and mine-impacted water. The conference, with its extensive program will also offer notable keynote speakers, student sessions and panel discussions, all with the purpose of giving a unique view into novel solutions and industry progression on the issue of mine-impacted water.

KEY BENEFITS OF ATTENDING THE CONFERENCE • • • • • •

High quality presentations Networking and knowledge transfer Local and international participation Comprehensive insight from stakeholders such as academia, industry and the government Free conference registration Virtual conference; attend from the comfort of your location

CONFERENCE TOPICS

Presentations related, but not limited to the following mine-impacted water related topics are invited: • Sustainable and innovative mine-impacted water treatment technologies • Waste to resource • Prediction and mitigation • Case studies • Mine closure practices • Legislation and policy drivers for sustainability • Novel and emerging strategies for sustainable management of mine-impacted water

CONFERENCE SCHEDULE The conference will be spread over 3 weeks in November 2020, with 2 sessions per week and 3-4 presentations per session. WEEK 1 – 10 and 12 November 2020 WEEK 2 – 17 and 19 November 2020 WEEK 3 – 24 and 26 November 2020

ECSA and SACNASP CPD Points will be allocated per session attended

PANEL DISCUSSIONS

Participants will be invited to take part in any of the panel discussions listed below during the dedicated panel discussion sessions. Note that there is no limit to the number of discussion sessions one can attend. • Sustainability drivers – outlook for industry government and academia • Role of the 4th IR and potential of the 5th IR as future solutions to mining and mine-impacted water • Prevention and remediation of mine-impacted water

STUDENTS SESSION

The conference will include a student session where postgraduate students working on mine-impacted water related projects will be given an opportunity to present their research projects. Students are requested to indicate during the submission that their abstract is for the student session. The best student presentation will be offered an award.

FOR FURTHER INFORMATION, CONTACT: Camielah Jardine, Head of Conferencing

E-mail: camielah@saimm.co.za Web: www.saimm.co.za