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By S. J. van Wyk, A. S. H. Haagner

Land rehabilitation transcends the mere establishment of vegetation across disturbed landscapes; it should be conceptualised as a specialised ecological reconstruction process. This process necessitates a long-term perspective on the success of land repurposing. It requires a continuum of inputs specified and managed by a dedicated and qualified custodian to ensure the sustained economic viability and ecological sustainability of the land. Based on the authors’ combined experience and field observations over more than five decades, they advocate for an urgent shift away from traditional land rehabilitation practices toward a paradigm centred on land capability reconstruction and active stewardship. The prevailing rehabilitation culture has overly simplified the process to a mere revegetation exercise, which is fundamentally incompatible with the comprehensive requirements for sustainable land capability. While the regulatory framework provides valuable guidance for obtaining a mine’s social license to operate, a paradigm reset is essential. Mining companies must prioritise rehabilitation quality, set achievable sustainability goals, and establish clear pathways and milestones to meet relinquishment criteria. Currently, the status quo view—a model reliant on outsourced contracting and agricultural approaches—is that mine rehabilitation is a one-time intervention rather than a complex, systemic, and long-term process. This perspective presents significant challenges, as the success of ecological interventions can only be accurately assessed over extended timeframes, often spanning decades. Shortsighted rehabilitation specifications, coupled with practitioners operating within agricultural decision frameworks, frequently overlook the necessity for integrated rehabilitation expertise and the scientific foundation essential for designing and implementing effective ecological outcomes. A lack of long-term monitoring information impedes the required adaptive management of rehabilitated systems and, therefore, delays the transition towards final land use. This short approach costs the mining industry millions annually, often without recognising the inadequacies in long-term liability mitigation and the substandard ecological success achieved. The disconnect between procurement processes, the qualifications of service providers, and the unclear pathways to relinquishment can impede successful rehabilitation outcomes, frequently undermining progress toward sustainability milestones. Unless there is a fundamental reset of the land rehabilitation culture, pursuing sustainability will remain an elusive and perhaps impossible objective. Consequently, mining companies may hesitate to fully commit to sustainable land rehabilitation practices, as the prospects for relinquishment and final closure remain uncertain at best.

Apr 25, 2025

By M. Mpofu, G. Stenzel, F. Magweregwede, B. Maphalala, T. Kgarume

Surface coal operations in which mining activities are conducted above old underground workings experience hot holes after drilling. In a coal mine, hot holes are defined as shot holes, which after being drilled have an in-hole ambient temperature of 40°C or above or show a temperature increase of 3°C or more during monitoring. Hot holes and other cavities, such as cracks, pose health and safety risks to workers, such as exposure to hot air and high concentrations of noxious gases released from these holes. In addition, workers may be exposed to premature detonation of explosives caused by in-hole temperature increases and chemical reactions. To this end, Coaltech Research Association commissioned a project to develop a Best Practice Guideline for the management of hot holes. This paper is a compilation of the activities conducted in the development of the Best Practice Guideline between 2021 and 2022. The activities included a review of standard operating procedures and hot-hole temperature-measuring and -monitoring devices, and the assessment of current hot-hole procedures at selected mines. The results indicated that management of hot holes requires a focus on pre-emptive risk assessment of mining blocks, identification of hot holes using the correct temperature-measuring devices, and continuous monitoring of hot holes from the time of drilling until just before blasting. Hot-hole management accessories, such as polyvinyl chloride sleeves, were found to be effective in insulating the hot-hole emulsion from the rock mass temperature, thus preventing the potential for premature detonation.

Sep 9, 2024

By Deur T. A. M. Saayman

Die sesde jaarlikse Ingenieursimposium is in September by YSKOR, Vanderbijlpark gehou. Rierdie simposium, wat deur Ingenieurs-in-Opleiding georganiseer word, bied aan die Ingenieurs-in-Opleiding die geleentheid om referate te lewer oor projekte wat gedurende hul drie jaar opleidingsperiode uitgevoer word. Continuing education courses The following courses are to be given in the near future in The Netherlands. Coal trade, transportation, and handling . The 4th Coal Trade, Transportation and Handling Conference and Exhibition, CoalTrans '86, will take place the Rai Congress Centre, Amsterdam, from 10th to 12th June, 1986.

Jan 1, 1986

The following are available from Metal Bulletin Books Ltd, Park House, Park Terrace, Worcester Park, Surrey KT4 7HY, England. . World aluminium-a Metal Bulletin databook. 2nd ed. 1990. £71.50 surface, £76.50 airmail. This is a compendium of information listing salient details of companies mining bauxite and producing alumina, primary aluminium, secondary ingot, master alloys, and semi-fabricated products; aluminium trading companies; and a memoranda section listing associations, brand names, and other useful information. It is a userfriendly international reference book for aluminium buyers, traders, and producers.

Jan 1, 1991

By J. N. Van der Merwe

The South African coal-mining industry uses a uniform safety-factor formula for non-squat pillars, incorporating a coal-strength constant that was derived empirically by Salamon and Munro in the 1960s. The constant is 7,2 MPa. Since that time, collapses of pillars at relatively high safety factors have occurred in the Vaal Basin. Analysis of the post-1960s' collapses indicated that the strength constant for the Vaal Basin is 4,5 MPa. A crude method for the prediction of the minimum life span of pillars in the Vaal Basin is presented.

Jan 1, 1993

By David J. Haddock

On Wednesday, 6th July, 1988, 28 members of the Johannesburg Branch of The South African Institute of Mining and Metallurgy and their guests assembled at the Rand Refinery Sports Club, which is situated within the Refinery complex, to hear Dr Daniel Polnow, General Manager of the Refinery, give a very interesting lecture on the Rand Refinery Complex and its activities. Accounting for gold The South African Institute of Mining and Metallurgy will be holding a 3- or 4-day school in the third week of May 1989 on the topic 'Accounting for Gold'.

Jan 1, 1988

By D. L. Morrison

The School on the Accounting for Gold, which was organized under the auspices of The South African Institute of Mining and Metallurgy by Dr Hugh E. Bartlet, Consulting Metallurgist of Johannesburg Consolidated Investment Company Limited, was held at the South African Nature Conservation Centre at Delta Park, Johannesburg, on 15th to 17th May, 1989. It was attended by 178 delegates, including 2 from the OK and 4 from Zimbabwe. A total of 19 papers were presented covering the components of gold-accounting procedure, sampling techniques, and new sampling technology.

Jan 1, 1989

By S. Banisi, S. M. Mousavi, S. D. Tafvizi, Gh. A. Parsapour, M. Mahmoudi

Generally, regrind circuits are used to increase the degree of liberation of value minerals which are fed to flotation circuits. At the regrind circuit of the Sarcheshmeh copper complex, four ball mills are in closed circuit with their hydrocyclone clusters. In the initial design of the plant, feed and underflow percent solids, and pressure drop of the hydrocyclones were 39% and 65%, and 15psi, respectively. Over the years, due to a reduction in the feed grade from 1.17% to 0.67% and changes in the operational conditions, the feed rate to each hydrocyclone cluster has decreased from 401 to 70t/h and consequently the pressure drop, feed and underflow percent solids have reduced to 4psi, 17% and 25%, respectively. The main objective of this research was to audit the feed solids concentration and pressure drop of the hydrocyclones and make the necessary modifications based on the Plitt’s model. The results of sampling showed that water recovery to underflow was 59% which was higher than normal values. By reducing the number of operating regrind mills from 4 to 2, the feed rate to each mill increased. After this modification and taking necessary measures in the plant to implement the new operating approach, the pressure drop, feed and underflow percent solids increased to 18psi, 28% and 58%, respectively. The water recovery of the hydrocyclones underflow decreased from 59% to 12%. These changes in addition to increasing the circuit efficiency saved 1000 kWh energy and decreased ball consumption by 925 ton/year because of reduction in the number of operating ball mills. Keywords: Regrind mills, flotation, audit, troubleshooting

Jan 1, 2020

By K. Richardson

Although the De Beers group has a long history of placer mining on land, the group only became actively involved in deep water marine diamond exploration and mining in1983 with the formation of De Beers Marine. Full-scale commercial mining commenced around 1991. Since then, the group marine mining capability has grown into a formidable fleet of 8 large deep water (>70 m) mining vessels, as well as other special purpose geo-survey platforms. Marine diamond production by the group is expected to be just short of 1 million carats in 2006. DeBeers operates across the entire value-chain spectrum from geology and geo-survey, through sampling to mining, and finally ore processing into high value concentrate. Supporting these operations involves significant service activities such as maintenance, security, logistics and environmental management. Specific challenges exist in terms of developing or acquiring appropriate technology for marine mining. These challenges have resulted in DeBeers operating extensive in-house R&D and projects departments, as well as drawing extensively from technology partners. An array of computational and test facilities are also available to support R&D and projects activities. Hydro transport in various guises is key to the current approaches to marine mining and ore processing. Use is made of airlift and centrifugal pumping for hydraulic hoisting of very coarse gravel, while splitters, launders, dewatering, elutriators, jet-pumps, centrifugal pumps, dense medium circuits, pipeline systems, and instrumentation for coarse abrasive particles are used extensively in the ore processing plant.

Jan 1, 2007

By A. Mehmet

The feasibility of employing a multi-stage column for the recovery of gold from cyanided pulps using extruded carbon was investigated on a pilot-plant scale. It was anticipated that the column contactor would have certain advantages over conventional carbon-in-pulp plants. The feed pulp was screened to remove particles larger than 200 µm and was diluted to a solids concentration of about 23 per cent. The column was operated continuously for 24 days at a pulp flowrate of about 60 l/min and a carbon flowrate of 44 litres per day. The average gold concentrations in the barren pulp 12 hours and 24 hours after the carbon transfer were 0,012 and 0,031 mg/l respectively. The average gold concentration in the solution phase in the feed was about 2,0 mg/L. The average gold Loading on the carbon was 6290 g/t. Calcium carbonate was removed from the loaded carbon by treatment with 0,5 bed volumes of 2,8 per cent hydrochloric acid solution at ambient temperature. The calcium concentration was reduced from about 17 000 to about 500 g/t The carbon was eluted by the Zadra procedure at atmospheric pressure. The results of the elution were highly satisfactory, the gold concentration being reduced from about 6000 to about 20 g/t in 48 hours. The eluted carbon was regenerated in a Rintoul kiln at about 700°C. The activity of the regenerated carbon was found to be at least as high as that of fresh carbon.

Jan 1, 1992

By N. B. Strydom

I have read with interest all the papers dealing with heat transfer and the setting of heat stress limits that have appeared during the past two decades. Scientifically speaking, most of them can be rated as being of a high standard, and some of them have been acclaimed internationally as masterpieces of logical and calculated reasoning. Weathering of ore minerals A short course on 'The Weathering of Ore Minerals and the Textural Evaluation of Base Metal Gossans' is to be given by Dr I.M. Reynolds in Grahamstown from 4th to 6th October, 1982.

Jan 1, 1982

By G. J. G. Juby

The Chamber of Mines Research Organization has been evaluating three membrane-desalination processes for use within the South African mining industry. These processes are electrodialysis reversal (EDR), tubular reverse osmosis (IRO), and slurry precipitation and recycle reverse osmosis (SPARRO). The evaluation of EDR and TRO is complete, and the operating costs (1988) associated with each process are expected to be about 50 cents per kilolitre for a plant of 50 l/s (4 Ml/d) installed capacity. The SPARRO process is still being evaluated. Pilot plant results, water Qualities, and expected capital costs are presented where appropriate.

Jan 1, 1992

Fig. 4 and 5 of the paper 'The analysis of ventilation and cooling requirements for mines' by J. van der WaIt, E. M. de Kock, and L. K. Smith are positioned incorrectly in the February issue (J.B. Afr. Inst. Min. Metal., vol. 83, no. 2, Feb. 1983). Extractive metallurgy of zinc At a professional development seminar to be held in Montreal (Canada) from 18th to 22nd April, 1983, specialists from industry and university will discuss the extractive metallurgy of zinc from ore to finished metal with special emphasis on the theory and practice of modern technology.

Jan 1, 1983

By C. I. Ware

The phrase ?back to basics? is used to describe the fundamental principles and philosophies on which a successful mining operation is based. At Richards Bay Minerals (RBM), ?back-to-basics? (BTB) has been implemented as a continuous process to probe operational functions with a view to increase production without capital expenditure. It also ensures that the fundamentals of dredge mining are understood and adhered to. BTB is based on the principle that people drive organizations, necessitating an interactive implementation approach. At the RBM mine this entails a three-pronged approach, namely practical training, teamwork initiatives and the use of lean Six Sigma methodology. It is the latter on which this paper will focus. The lean Six Sigma methodology is successful in identifying, managing and documenting BTB projects, while team work initiatives are integral to successful project implementation. This paper describes two examples of how the Six Sigma methodology can be applied to a dredge mining operation. The first example focuses on the improvement of Mining Pond Echo (MPE) plant throughput by reducing the lost opportunity (non-production) due to tails downtime. The project was successful in increasing plant throughput by 4.5%. This was achieved by increasing the tails disposal system availability by running MPE as a four tails lines operation and focusing on causes of tails production downtime. Subsequently, the tails system at MPE is no longer the production bottleneck. Second, the Six Sigma methodology was successfully applied at Mining Pond Charlie (MPC) to increase the primary dredger throughput by 4.6% through focusing on the dredging technique and maintenance issues. This project highlighted the need for trend analyses to ensure an effective dredging technique, coupled with simple production documentation, which also ensures a focus on maintenance. Keywords: Back to basics, Six Sigma, training, teamwork, throughput improvement, tails, dredger.

Jan 1, 2007

O.F.S. Branch Minutes of the Committee Meeting held in the Committee Room at the St. Helena Club at 4.45 p.m. on Wednesday, 3rd September, 1975. Book reviews JONES, M. J. (ed.). Minerals and the environment. London, Institution of Mining and Metallurgy, 1975. Mining Companies of the world.. 1974/75. London, Mining Journal Books Ltd (15 Wilson Street), 1975. £12. 303 pp. NIM reports Report no. 483 Summary of the mineralogical investigation of pegmatites. (11th April, 1969; re-issued October 1975). Report no. 1697 A petrographic and mineralogical investigation of silica samples from the farm Elandskraal 470JQ, Rustenburg district. (24th Jan., 1975; reissued October 1975). Report no. 1761 The determination, by atomicabsorption spectrophotometry, of minor elements in anode sludges and residues. Report no. 1762 The determination, by instrumental neutron-activation analysis, of some elements in the NI M ROC standard reference materials. Report no. 1770 The spectrophotometric determination of vanadium in chromiumbearing materials. Foundry conference An international foundry confcrence, spomored and organized by South African Institute of Foundrymen, will be held in Johannesburg from 23rd to 27th February, 1976. The themes for each day are follows: Coordination chemistry A symposium on coordination chemistry in extractive metallurgy is to be held in Kelvin House, Johannesburg, on 18th and 19th March, 1976. Practical jet cutting The third international symposium on jet-cutting technology to be organized by BHRA Fluid Engineering will be held in Chicago from 11th to 13th May, 1976, in conjunction with the lIT Rese:uch Institute of Chicago. Hydraulic transport The fourth international conference on the hydraulic transport of solids in pipes (Hydrotransport 4) is being organized by BHRA Fluid Engineering.

Jan 12, 1975

By C. J. Lenz

The results of prospecting operations involving geological data and a large number of geochemical determinations of the metal content of soil samples are plotted and evaluated by computer. Anomalous areas are identified in each type of environment by selecting probability or population boundary values from frequency distributions. The anomalies are plotted to permit correlation with geographical or geological features. Ranking of prospecting targets is made using geographic pattern, geology, absolute value and metal ratios. Three short case histories are presented.

Jan 1, 2014

By J. T. Nel

The Kroll process is the traditional method of producing zirconium metal by reduction of zirconium tetrachloride with magnesium metal. This paper discusses the production of zirconium metal in a plasma reactor. Anhydrous low-hafnium ZrCl4 and Mg metal were fed continuously to a 30 kW non-transfer plasma reactor at a rate of 0.31 kg.h-1. Due to losses in the system the recovery of crude product was 77.5 %. After purification to remove unreacted feed material and MgCl2 by leaching, >98 % pure zirconium metal powder was obtained. The overall recovery of purified Zr was 74 %. The conversion efficiency of the process was 95 %.

Jan 1, 2012

By A. Becker, R. Tait, S. L. George, A. Carlisle

Surface treatments like laser shock peening (LSP) induce residual stresses penetrating up to 1 mm deep, surpassing traditional methods, thus significantly increasing the potential impact on materials prevalent in the automotive and aerospace sectors. Through extensive fatigue testing and fractography investigations, it was determined that LSP resulted in a fatigue life increase of over five times for aluminium alloy AA7075-T6 and titanium Ti-6Al-4V. Increased fatigue life was also noted in AISI316 stainless steel, which showed increases in fatigue life of 1.7x. While fatigue life in all cases improved, the efficacy of LSP was shown to be material dependent.

Jul 23, 2025

Results from a study undertaken at a Transvaal colliery on the feasibility of undermining an urban development by conventional bord-and-pillar mining operations in the No. 4 Seam of the Highveld Coalfield are discussed. Surface ground vibrations above production sections were measured, analysed, and then compared with well-accepted guidelines so that the expected effects of vibration on inhabitants and surface structures could be determined. The measurement and scaling of ground vibration from blasting are outlined, and the effects on humans and structures are discussed. It is concluded that residential areas can be safely undermined by conventional drilling and blasting techniques provided certain simple guidelines are followed.

Jan 1, 1987

Council and Standing Committees, 1975-1976 President: Dr R. E. Robinson. Vice-Presidents: Dr M. D. G. Salamon and P. A. von Wielligh. Honorary Treasurer: J. K. E. Douglas. Immediate Past President: Prof. R. P. Plewman. Members of Council: Dr M. G. Atmore, J. D. Austin, C. T. Fenton, J. A. Holmes, P. Holz, Dr P. R. Jochens, Prof. R. P. King, Dr D. G. Krige, Dr D. I. Legge, D. G. Malan, C. T. Shaw, D. A. Viljoen, R. A. von Maltitz, H. M. Wells. Chairman, Witbank-Middelburg Branch: E. J. Jackson. Chairman, Orange Free State Branch : G. J. C. Young. Past Presidents Serving on Council: R. J. Adamson, H. Britten, H. E. Cross, J. K. E. Douglas, R. C. J. Goode, Prof. D. D. Howat, Dr J. P. Hugo, D. M. Jamieson, D. G. Maxwell, Dr J. T. McIntyre, V. C. Robinson, P. W. J. van Rensburg. Seven Council meetings and five Executive Committee meetings were held during the year, and the standing and sub-committees held fifty-five meetings. Standing Committee Chairmen Membership, P. A. von Wielligh ; Technical Programme-Metallurgy, D. A. Viljoen; Technical Programme-Mining, D. G. Malan; Vacation School-Metallurgy, Dr P. R. Jochens ; Vacation School-Mining, H. M. Wells; Awards, Dr R. E. Robinson; Excursions, Dr D. I. Legge; Adjudicating, Dr R. E. Robinson; Constitution, Rules and Policy, Prof. R. P. Plowman; Mines and Works, C. T. Shaw; Education, Prof. R. P. Plewman; Foundry Colloquia, Prof. D. D. Howat. Representatives on Other Bodies Associated Scientific and Technical Societies: Members : Dr R. E. Robinson and Prof. R. P. Plewman. Alternates : P. A. von Wielligh and Dr M. D. G. Salamon. Federation of Societies of Professional Engineers: Members : J. K. E. Douglas and Prof. R. P. Plewman. Alternates: Dr R. E. Robinson and Dr M. D. G. Salamon. FSPE Technicians Committee: Member: D. M. Jamieson. FSPE Rationalziation Committee: Member: Dr M. D. G. Salamon. South African Council for Professional Engineers (Institute Nominees) Member : R. C. J. Goode. Alternate: G. H. Grange. South African National Committee on Tunnelling: Member : D. G. Malan. Alternate: Prof. R. P. Plewman. Engineers' Liaison Committee (Pretoria) Member : Dr J. P. Hugo. Alternate : P. W. J. van Rensburg. Government Certificate of Competency Liaison Committee: Member: Prof. R. P. Plowman. Alternate: D. M. Jamieson. James Moir Memorial Lectures: Member : Prof. D. D. Howat. World Mining Congress-National Committee: Members : Dr M. D. G. Salamon, Prof. R. P. Plewman, and H. M. Wells. I.F.A.C. Symposium: Member: P. W. J. van Rensburg (Chairman-Organising Committee). Alternate : Dr J. P. Hugo. I. U.P.A.C. Symposium: Member: Dr P. R. Jochens. Membership Nine Fellows, twenty Members, six Associate Members, thirteen Graduates, nine Associates, twenty-nine Students, and ten Company Affiliates were elected during the year. One Fellow was elected to Honorary Life Fellowship, eight Members and one Graduate were transferred to Fellows, twelve Graduates and two Students were transferred to Members, three Students were transferred to Graduates, and one Student was transferred to the grade of Associate. Six Fellows, two Members, and two Associates were admitted to retired membership. Nine Fellows, fifteen Members, three Graduates, one Associate, two Students, and one Company Affiliate resigned. A statement of membership as at June 30th, 1976, and the end of the previous year is shown in the following tabulation. 30th June, - 30th June, 1975 1976 Honorary Life Fellows 16 - 17 Honorary Fellows 8 - 8 Life Fellows 171 - 171 Fellows 549 - 547 Members 523 - 517 Associate Members 15 - 21 Graduates 132 - 123 Associates 209 - 205 Students 173 - 179 Company Affiliates 71 - 80 1866 -1878 Obituaries Your Council records with deep regret the death during the year of the following members: P. A. Creewell, Life Fellow; A. S. Davis, J. S. Hay, P. 0. Lange, N.

Jan 10, 1976