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By Edward A. Nowatzki

The purpose of this paper is to present an example of the application of a theoretically derived mathematical model for track-soil interaction to the evaluation of the mobility of large-scale mining equipment used in open pit operations. The model described by Karafiath and Nowatzki (1978) and presented in detail by Karafiath (1978) was used to predict the performance characteristics of four different bucket wheel excavators (BWEs) on rwo types of copper mill tailings at various moisture conditions. The BWEs considered In the analyses are two-and three-tracked continuous excavators. Most have boom-mounted rotating buckets and swinging side- or rear-discharge conveyors. The analyses were performed at the request of Dames and Moore for the Kennecott Corporation's proposed remining of selected tailings deposits at the McGill, Nevada, concentrator. The objectives of the analyses were to determine whether BWEs would have sufficient mobility In the tailings deposit to achieve satisfactory production rates, and TO compare the predicted performance of the various BWEs evaluated. Good qualitative agreement was obtained between the results of the theoretical analyses performed for the McGil1 operation and the actual performance of BWEs in two South African gold mine tailings impoundments.

Jan 1, 1980

By Ronald L. Gibbs

IN THE BEGINNING Contrary to popular myth, the personal computer can trace its roots back to a time before 1981 and the IBM PC. The seeds of the personal computer revolution were probably founded in 1975 with the release of the Altair (kit) personal computer, first advertised in Popular Electronics. June of 1975 marked the beginning of the Homebrew Computer Club in San Francisco. The founding membership list of the Homebrew Club now reads like a "Who's Who" of those involved in the early development of the personal computer industry. The Apple I computer was created by Steve Wozniak in early 1976 from the newly manufactured MOS Technology 6502 chip. It had 4,000 bytes (4K) of Random Access Memory (RAM] memory, a revolutionary amount of memory in 1976. Another early pioneer, the Commodore Pet computer, was another 6502 machine, but with 8K of memory. Tandy Corporation made its name in the hobby industry with leather kits. They embarked on a new path with the production of the TRS-80 line of personal computers. Most were based on the Z-80 chip, but again, were memory limited. A number of other Z-80 based systems followed later, including the Osbourne and the KayPro Computers. These systems were based on the Digital Research CP/M operating system and had a maximum of 64,000 bytes of memory (64K). The Apple I1 Computer appeared in 1977. Newer models of the original Commodore Pet and an Atari computer followed. These machines were also limited to 64K of memory addressing, and the early models typically shipped with only 16K, 32K, or 48K of memory. The Z-80 and the 6502 were the first truly commercialized CPU chips touting boxes with key- boards, monitors (sometimes a TV), and the ability to expand (peripheral slots for serial communications, centronics parallel communications, etc.1. They all shared one technology, audio tape as a storage media. The use of a portable tape recorder provided inexpensive, if not always reliable, magnetic storage. The tape recorders were typically finicky and required patience to use. Adjustments to the volume control were often needed to find "just-the-right" setting for loading or saving information. This kept the personal computer from being accepted in many markets, and gave it a reputation as a hobbyist or experimenters' toy. In early 1979, Steve Wozniak finished the design of a floppy disk drive and controller. This was a revolutionary design which reduced the "then" standard number of controller chips from fifty-plus, to just eight. With the advent of an affordable floppy disk drive mechanism, the personal computer was about to gain respectability. From a business standpoint, it was now possible to save and reliably retrieve business information. It also provided a superior means of distribution for commercially created software. Commercial software became a commodity rather than an oddity.

Jan 1, 1993

By D. C. Martin

Stability analysis and design of open pit slopes is generally based on an assessment of rock cores and rock exposures on surface or in underground workings. Until recently, core for such assessments has been readily available from exploration drilling programs. In recent years, many exploration programs have reduced the amount of coring and rely more heavily on less expensive rotary or percussion drilling programs where drill cut-tings are sampled for geological evaluation and assay. This paper describes a technique whereby costs of the geotechnical investigation are reduced by using rotary percussion drilling information to assess geotechnical properties of the rock mass. A limited number of core holes are required to establish basic relationships between the mechanical properties of core and the characteristics of the percussion chips. These properties are used as a basis to extrapolate the coring information to encompass the entire area of the rock mass for which percussion drilling information is available.

Jan 1, 1990

By S. T. Hall

The authors have previously described a method of enhancing the magnetic susceptibility of pyrite by a mild alkaline oxidative pressure leach (Hall et al, 1985). This finding was successfully applied to enhance the magnetic desulfurization of an Eastern Canadian coal (Hall and Finch, 1984). This paper reports on enhancement of the magnetic susceptibilities of iron-containing sulfides (arsenopyrite, chalcopyrite and marcasite) upon similar treatment. It also explores the application of this pretreatment in the magnetic separation of fine sulfides from oxides and other sulfide minerals. In the latter case galvanic interference effects have a serious impact on the potential use of this method.

Jan 1, 1985

By Rollin A. Slater

The bulk materials handling industry has served silently for years as the skeleton structure and often the central system of nerves and nourishment for the body of basic production industries. During the past two decades, this body has undergone substantial growth and mutation to meet the surging demands of our national economy for more and better products. The steel industry has been prominent in this phenomena and plants of the sixties are as unlike the second war vintage as our current crop of basketball players differ from their fathers. Steel has kept pace with spiralling demand by innovation which has resulted in new processes and improved designs which generally yield greater production from fewer units. The supporting industry of materials handling has likewise improved its techniques and currently has a new stronger generation of equipment to perform its necessary supporting function. It has been my fortunate experience to have been instrumental in the creative stages of several new steel mills which are currently in conceptual design or actual construction. Drawing upon exerpts from this experience, this paper will describe a basic approach to the selection and application of modern bulk materials handling systems to an entirely new steel plant. Specific details of past work are not available for publication, therefore, the plant described herein is a composite of ideas and will be the new plant of the Hypothetical Steel Corporation which will be located on the lower shores of the Great Lakes.

Jan 1, 1967

By David Atkin

This paper presents methods and results of environmental planning conducted for a proposed coal and iron ore transshipment terminal which would be located on reclaimed land west of Lisbon, Portugal. Oceanographic, navigational, marine, structural, material handling, and financial studies of the terminal were conducted along with the environmental analyses. However, because of the proximity of the terminal to heavily used recreational resources, residential areas, and biologically valuable habitat, anticipating and reducing the environmental effects of the terminal to minimum levels was a very important part of the overall project. The results of the study indicate that even the impacts associated with worst-case conditions would be acceptable because of appropriate pollution control measures and planning.

Jan 1, 1983

By A. Patrick Ryan

To many people, the word cartel implies illegality. However, although it is illegal in the US, cartels are an effective and legal way to conduct business elsewhere in the world. But be-fore we continue, what is a cartel? The American Heritage Dictionary defines a cartel as "a combination of independent business organizations formed to regulate production, pricing, and marketing of goods by the members." However, that definition does not fit many of the "cartels" we are examining today. The International Tin Council is an organization of both consumer and producer nations--no individual companies are represented. The buffer stock is used by the ITC to provide protection for both producers and consumers, and has only been in effect since 1955. (Earlier tin producers groups date back to 1921 when the Federated Malaysia States and the Netherlands East Indies formed the first intergovernmental tin agreement, known as the Bandoeng Pool, which only lasted three years.) The International Bauxite Association only dates back to 1974 when seven nations--Australia, the Dominican Republic, Ghana, Guinea, Guyana, Haiti and Jamaica--agreed to three main objectives: 1) to promote the orderly and rational development of the bauxite industry; 2) to secure a fair and reasonable return on the raw material for the benefit of the nations' citizens; and 3) to safeguard the interests of member countries in relation to the international bauxite industry. 1 Again this organization is composed of nations, not separate firms. This generally follows the pattern that the oil producing countries (OPEC) chose since the nations' mineral product-ion is controlled and often owned by the state. However, the group I am going to discuss fits the more classic mode of a cartel. The informal lead-zinc producers' cartel can be dated as far back as to Roman times when Romans are said to have imposed a quota system on British lead production to safeguard their Spanish lead mines. Also, the lead-zinc producers group is composed only of individual companies, not do not include any lead-zinc consumers. Finally, the activities of the group are not open to public scrutiny, and details are only now available due to a leak in the Australian government. At this point, it is necessary to split the two metals since while many of the members of the cartels produce both lead and zinc they do have different histories and marketing arrangements.

Jan 1, 1978

By Greg Sanders, Bill Lueck, Michael Gilbert, Mahmood Khwaja

"The city of Minneapolis contracted with CDM Smith to update and provide a conceptual design for improvements to mitigate surcharge flooding in the Central City Storm Water Tunnel System (CCSTS). As a part of the project, CDM Smith conducted a field survey and condition assessment of the existing tunnel system. Information from the survey was then used to update the existing XPSWMM model and develop system wide alternatives.The CCSTS provides storm-water runoff drainage for nearly the entire area of the city’s downtown commercial district. The system consists of deep storm-water tunnels constructed in the St. Peter Sandstone, approximately 21 m (70 ft) below the street’s surface. The primary tunnels comprising the Central City storm water tunnel system are located below Hennepin Avenue, Nicollet Mall, Lesalle Avenue, Marquette Avenue South, 2nd Avenue South, South 5th Street, Washington Avenue South, Portland Avenue South, 2nd Street South, and Chicago Avenue South, as shown in Fig. 1. This network of tunnels conveys the runoff from a 305-acre tributary area that is generally bound by Hennepin Avenue and 1st Avenue North to the east, 12th Street to the south, 4th Avenue South and 7th Avenue South to the west, and 2nd Street South. These tunnels were constructed between 1936 and 1940, except for the Marquette Avenue South tunnel, which was constructed between 1963 and 1964.The CCSTS operates as a gravity flow system. These tunnels were constructed within the St. Peter Sandstone layer of bedrock and emerge from the bedrock at the Mississippi River below St. Anthony Falls. The Central City and the adjacent Chicago Avenue tunnel system converge into a single outfall at the Mississippi River. The runoff discharges from the converged outfall to a side channel of the Mississippi River, called a tailrace, located near the Guthrie Theater. The Minneapolis Division of Surface Water and Sewers provided 32 historic plats detailing the plan and profile of the tunnel system.The tunnel plans show nine different cross-section configurations. Eight configurations within the overall system generally show the same geometric “cathedral” shape with the inside dimensions varying from 1.2 to 1.8 m (4 to 6 ft) in width and 1.8 to 2.4 m (6 to 8 ft) in height. For analysis, these eight configurations were reduced to three configurations with regards to tunnel liner, cross-sectional area and support. For simplicity, the three configurations are described according to the three types of tunnel support used during construction: none required, light timber and heavy timber"

Jun 1, 2019

By A. Mertzanis

The way and methods used for the surface mining of bauxite until the end of the twentieth century in the area of Ghiona, resulted in a significant burden to the natural environment, especially in the cases where it covered extended parts of forests and forest areas as well as important geomorphological formations. The impacts from the surface mining of bauxite which in fact constitute the object of this study relate mainly to the interruption of the natural continuity of the land relief and the alteration of the natural geomorphological activities and are due to: a) the alternating excavations with fronts of great heights, b) the depositions of large volumes of waste materials which originate from the revealing of the ore and c) the dense road network constructed in order to get access to the mine locations.

Jan 1, 2006

By Emily Wortman-Wunder

As the 2009 president of the Society for Mining, Metallurgy, and Exploration, Inc., I am pleased to present the 2009 issue of Transactions of the Society for Mining, Metallurgy, and Exploration, Vol. 326. A significant portion of the contribution that we as a society make is the publication of professional and technical papers that contribute to the advancement of scientific knowledge and information transfer. Communication within the mining community is the key to a successful society. Through the information-transfer mechanisms of books, magazines, meetings and electronic media, the technology exchange that is fundamental to the existence of the Society is accomplished. This technology exchange continues a tradition that dates back to the 1871 meeting of 22 mining engineers in Wilkes-Barre, Pennsylvania, that resulted in the founding of AIME; those individuals envisioned that these transaction volumes “would form a most valuable and greatly needed addition to our professional literature.” This volume certainly satisfies that intent. In keeping with SME’s tradition of promoting technological developments while honoring the past, the 2009 Transactions represents an important milestone. It is the last Transactions to appear as a bound volume. Future volumes will appear as e-books only, with some of the Transactions-only papers appearing online prior to the ebook (exactly what form the new Transactions will take is still in development). The decision to go to an all-digital format for this longstanding publication was a difficult one, but one which we hope will better serve the mining community, especially our international members. This 2009 Transactions of SME, Vol. 326, contains a total of 73 technical papers (510 pages), including all 23 papers (136 pages) that were published in 2009 in the Technical Papers Section of Mining Engineering magazine (Vol. 61) and all 32 papers (232 pages) that were published in 2009 in Minerals & Metallurgical Processing (Vol. 26). In addition, this volume contains 18 papers (142 pages) that are being published for the first time in this issue. The papers presented in this volume were written by some of the most distinguished professionals in the industry worldwide. All 73 technical papers were peer-reviewed and approved. The process of review and publication requires much hard work by authors, reviewers and publications staff. As the 2009 president of SME and on behalf of our members, I would like to extend our gratitude to all whose efforts contributed to the publication of this volume.

Jan 1, 2009

The 25th Peruvian Mining Convention (Convención de Ingeneieros de-Minas del Perú) was held Sept. 10-14, 2001, in Arequipa, Peru. The biennual meeting, sponsored by the Peruvian Institute of Mining Engineers (Instituto de Ingeneiros de Minas del Peru), is designed to showcase the Peruvian mining industry and to ?promote progress in the national mining sector.? The convention consisted of technical sessions, forums, field trips and social activities. The technical sessions featured 80 papers selected from more than 200 papers submitted. The well-organized 2001 meeting was held at the Tecsup Institute of Technology of Arequipa. The meeting was held in conjunction with Exposición Technologica Minera (Extemin), a mining trade exhibition. The2001 Extemin had representatives from more than 400 companies in attendance. In addition to the many Peruvian companies present, the trade exhibition featured pavilions representing the United States, Canada, Germany, Australia and Chile. Registration at the 2001 meeting was about 3,300, a conference record. The theme for the 2001 meeting was Mining: Society and Development. Mario Brescia was chairman of the organizing committee. He said in his opening remarks that ?this year?s meeting seeks to emphasize the commitment on the part of the [mining] companies to treat our natural resources responsibly, controlling any adverse impacts and giving priority to group benefits.? Consistent with this theme, many of the technical papers stressed environmental and social responsibility. Many successful examples of environ-mental and social responsibility on the part of the mining industry were presented in the technical sessions.

Jan 1, 2001

By R. J. Sheets

"What is the primary responsibility of geo-engineers in mining? Early in my career, I was asked this question by an experienced engineer. After explaining some various tasks, I was informed that the main responsibility was to monitor. Although this proved true for many cases, I came to understand that monitoring is merely one means to achieve the primary responsibility of a geo-engineer — ensure the safety of all personnel. The potential for groundwater to impact stability allows this responsibility to be shared with hydrogeologists as well. Inherently, we monitor to identify risks; we analyze designs and develop models to mitigate risks; and we are provided opportunities to explain to supervisors the geo-risks to personnel and mine plans that will result from particular courses of action. A couple years ago, I took an opportunity to share experiences from the first several years of my career as a geotechnical engineer with junior geoengineering staff within my company. The intent was to share situations that were a part of my development, so they could learn and understand their responsibility to the safety of all personnel. Similarly, the purpose of this article will be to share these thoughts with new geo-engineers in the industry in order to help prepare them for the challenges they will face.What is our purpose?A senior hydrogeologist shared an experience that occurred in their career. The experienced hydrogeologist had spent some time with the hydrogeology staff, most of them relatively new to the mining industry, to understand how they viewed, and carried out, what they perceived as their responsibility at an active mining operation. After a couple months of observing and mentoring, the senior hydrogeologist met with everyone and posed the question “What is our purpose?” I am sure that most junior geo-engineers would start explaining different tasks or projects that they must complete. The list would include monitor ground water levels, track slope movement, evaluate designs, build models, oversee drilling programs, etc. These individuals did as well their supervisor. After going around the room allowing each individual to answer, the experienced hydrogeologist provided them the real answer to the question: Safety. If you examine the root intent of nearly every responsibility geotechnical engineers and hydrogeologists have, it is to apply our professional skills to ensure the safety of our workforce. When the objective of safety from the geotechnical and hydrogeology disciplines is achieved, inherently accomplishing the mine plan should follow suit, or it should significantly minimize the impact by gravity or ground water."

Jan 9, 2018

By Muhammad Azeem Raza, Samuel Frimpong

Underground mining environments are inherently hazardous and can lead to emergencies where effective rescue and self-escape become critical. Missouri University of Science and Technology is pioneering new technologies for effective self-escape. The rescuers and miners need to be trained in these new technologically driven environments. Previous research in fields like aviation, medical surgery, and oil and gas drilling has demonstrated the effectiveness of virtual simulation training, but the mining sector has yet to fully adopt advanced tools such as eye-tracking and immersive training modules. This research proposes a comprehensive training infrastructure incorporating these technologies to enhance situational awareness and decision-making during emergencies. The novelty lies in the application of advanced miner escape and communication technologies, specifically designed to monitor and enhance cognitive responses in high-stress situations. By leveraging these technologies, the proposed training infrastructure aims to prepare the next generation of underground miners and operators, by equipping them with the necessary skills to manage emergencies effectively.

Feb 1, 2025

By K. A. Natarajan, Abha Kumari

"The effect of applied DC potentials on the bioleaching of a chalcopyrite concentrate in the presence of Acidithiobacillus ferrooxidans is discussed. Copper dissolution was the highest at an applied potential of +600mV (SCE), while all the dissolved copper got cathodically deposited at a negative potential of -600mV (SCE). Electrobioleaching at an applied potential of +600mV (SCE) was established at different pulp densities as a function of time. The effect of applied potentials and electrolytic currents on the activity and growth of bacterial cells was assessed. Preadaptation of bacterial cells to the concentrate slurry and electrolytic growth conditions significantly enhanced copper dissolution. Electrochemical and biochemical mechanisms involved in electrobioleaching are illustrated with respect to oxidative dissolution and biocatalysis of anodic oxidation. IntroductionIn recent years, the bioleaching of low-grade chalcopyrite ores as well as their flotation concentrates has been receiving increased attention. Use of mesophilic bacteria such as Acidithiobacillus ferrooxidans in the bioleaching of chalcopyrite does not yield desirable copper extraction rates due to its easy passivation.Bioleaching of chalcopyrite using A. ferrooxidans has been reported to be very inefficient, and use of thermophilic bacteria at higher temperatures is recommended to improve its bioleaching rates. Bioleaching under imposed applied DC potentials or currents has been shown to enhance not only bioleaching kinetics but also to confer selectivity in mineral dissolution (Abhakumari, 1996; Chirpa Selvi and Natarajan, 1998; Natarajan, 1992a, b,c). Electrochemical principles governing electrobioleaching have been earlier illustrated (Jyothi et.al, 1989). The role of applied potentials on the activity and growth of A. ferrooxidans has also been studied (Natarajan, 1992b). Also, the electrochemical aspects of bioleaching of several sulfide minerals when present alone or in binary and ternary combinations have been reported (Jyothi et al., 1989). The electroleaching of copper-nickel concentrate (Natarajan et al., 1985) and electrobioleaching of sphalerite concentrates have already been studied (Selvi et al.,1998). However, it is possible to enhance the bioleaching rate of chalcopyrite in the presence of A. ferrooxidans under galvanic conditions in the presence of nobler minerals such as pyrite (Jyothi et al.,1989). Also, dissolution of chalcopyrite can be significantly enhanced under applied potential conditions. Ali Ahmadi and his coworkers recently studied the electrochemical bioleaching of chalcopyrite concentrates using moderate thermophiles (Ahmadi et al., 2010, 2011)."

Jan 1, 2015

By Conrad W. Steller

What is the definition of a successful construction or development project? It could be described in many ways: a project that performs as designed; a project completed on time, a project completed within budget. The title of our talk today is, "The Advantages of Applying Design/Build -Construction Management to the Mining Industry." As our talk develops, you will see that rather than tell you how to apply this concept, we will discuss the advantages and details of Design/Build so that you can independently apply the concept. Design/Build is not new, and it cannot be universally applied. It has, however, within the past ten years, carved a specific and substantial place in the overall construction -development market. The reasons for its rather recent rise to considerable prominence as a concept is due, in part, to the increasing urgency of gaining productive access of a production facility and, in part, to the inherent advantages of the concept's economics--and they are considerable. If the Design/Build concept of contracting were fully understood, it would, without exception, be the favored way for private industry to contract for its new construction and development as well as renovation work. The basic advantages are: earliest possible access and completion at the lowest cost. Design/Build is often equated and compared to "fast track" or "turnkey" methods of construction. The Design/Build concept can, in fact, be both of these or neither. "Fast track", in and 6f itself, implies that the project will be phased construction, that is to say, it will be built quickly; whereas I "turnkey" is a measure of the completeness of the project, usually meaning essentially that the

Jan 1, 1977

By A. Chieregati

"A heterogeneity study was conducted at Erdenet Copper Mine in Erdenet, Mongolia, to determine the fundamental sampling error associated with blasthole sampling. Using a custom-designed radial sector sampler , six large blasthole samples were collected to perform the test developed by Pierre Gy to estimate the constitutional heterogeneity factor for several types of ore. The study investigated the entire sampling protocol, from mine site to analytical laboratory, and quantified the contributions to total fundamental sampling error (FSE) of the various stages of sampling and sample preparation. The total relative standard deviation (RSD) of sampling error was determined to be ±32 percent and ±49 percent for copper and molybdenum, respectively. A classical statistical analysis conducted on the data confirmed the level of RSD native to the mine. About 95 percent of the sampling error was produced from one step in the sampling protocol, that of reducing the 1-kg (2.2-lb) sample to a 50-g (0.1-lb) sample for chemical analysis. To minimize the FSE, the use of a slightly different protocol is recommended. The 1-kg sample (2.2-lb) should first be crushed to a 0.2 cm (0.08 in.) particle size. A 250-g (0.5-lb) split should then be taken and finely ground, from which a 50-g (0.1-lb) split should then be taken. These simple steps will reduce the FSE to ±7.9 percent and ±17 percent for copper and molybdenum, respectively. The modified sampling protocol effectively reduces to zero the probability of misclassification of low-grade ore. IntroductionThe Erdenet copper-molybdenumopenpit mine is located in Erdenet in Orkhon province, Mongolia. The Erdenetiin-Ovoo copper-molybdenum deposit is 1.5 to 3 km (0.9 to 1.8 miles) wide and about 25 km (16 miles) long (Erdenet Mining Corp., 2016). Chalcopyrite, bornite covellite and chalcocite are among the major minerals found in the deposit. The mine processes approximately 26 Mt/a (29 million stpy) of ore."

Jan 11, 2017

By Alexander E. McHugh

A study of some variables affecting the recovery of molybdenum from oxidized molybdenum minerals was made. The effects of variations in contact time, temperature, pulp density, particle size, and solvent concentration on the recovery of molybdenum using acid and alkaline solvents were investigated. Chemical analyses, screen analyses and microscopic examinations were made and the presence of important elements determined. A hydrometallurgical method was developed to recover the molybdenum from the oxidized molybdenum ore by simultaneous dissolution of the molybdenum with sulfuric acid, adsorption on activated charcoal and flotation of the charcoal. The molybdenum was extracted from the activated charcoal with sodium hydroxide, precipitated with calcium hydroxide as calcium molybdate and this regenerated sodium hydroxide for additional stripping. A solvent extraction method, using mines, was also studied to recover molybdenum from both alkaline and acid molybdenum solutions. Satisfactory results were obtained.

Jan 1, 1967

By William C. Peters

The Alpine-Himalayan system, the only major active tectonic belt mainly exposed in a continental mass, is of increasing interest to exploration geologists as well as to theoreticians. Answers to the broader problems of plate tectonics are being sought in this intricate system where the geosynclinal concept was born and where the geotectonic cycle was first applied to metallogeny. The search is all the more intense because it involves scientists from more than a dozen countries with a stimulating variety in perspective. The international Geodynamics Project has allocated the Alpine-Himalayan system to two separate study groups with one directing its attention to the Alpine-Mediterranean region and the other giving consideration to the Himalayan region. This geographic division is accepted in this paper, with remarks being confined to the former and to the west of boundary zone between the European-Asian and the Southeast Asian plates as envisioned by Dewey and Bird (1970). The region is well-mapped in some parts and it includes some of the most intensely-studied geology, most classic mines, and newest orebody discoveries. Within the region, an Alpine-age copper-molybdenum metallogenic belt extends from Rumania to Pakistan. The belt can be considered in terms of plate tectonics, and there is the possibility of using plate tectonics concepts in exploration.

Jan 1, 1973

By Sakshi Hazuria Anderson, Angela Binder, Oscar Jaime Restrepo Baena, Simit Raval, Sandra Nowosad

As the mining industry faces times of change, new challenges arise to ensure raw material supply for the younger and future generations. Different scenarios are currently shaping the way we mine and teach mining engineering. Led by an increasing demand for raw materials, net zero requirements for improving long-term operation performance, technological advancements such as automation and digitalization, safety improvements, environmental considerations and a need for social acceptance, mining is pursuing to change and adapt to these requirements at a faster pace. Such changing times raise new concerns, one of the most relevant is the lower number of students interested or enrolling in mining engineering and related fields leaving mining engineering as one of the less preferred career options between the younger generations. Nonetheless, it is essential to continue addressing and supplying the skill sets that are suited to the contemporary and future mining industry. To this end, globally, academia is currently undergoing several initiatives such as curricula updates and adaptation, up skilling, improving teaching practices and techniques, including e-learning techniques, enhancing industry-academia and inter-university collaboration, and much more. In countries like Australia, where mining plays a crucial role in the economy, the need for curriculum updates is more pressing than ever. As the mining industry evolves with new technologies and sustainable practices, there is a growing demand for a workforce skilled in these modern approaches. Recognizing this necessity, universities such as the University of New South Wales and Curtin University have taken significant steps to revamp their educational programs. By updating their academic offerings, both universities aim to equip graduates with the necessary skills to drive innovation and sustainability in mining, supporting Australia’s development as a leader in this critical sector. Moreover, the selection of topics that drive curricula update and the focus of the research institutions in mining engineering must extend beyond mere technological and technical aspects to include social and ethical dimensions. In this context, the Universidad Nacional de Colombia, in association with the Colorado School of Mines, has introduced the topic of Humanitarian Engineering (HE) in 2020. HE is a socio-technical approach that focuses on developing engineering solutions that promote the sustainable development of communities addressing their basic needs and aiming to improve their quality of life (10, 18). By focusing on sustainable development, community engagement, and equitable resource distribution, HE helps the industry build positive relationships with stakeholders, reduce conflicts, and foster social license to operate. As the mining industry seeks sustainable and socially responsible practices, future engineers require training in this area to understand the broader impacts of their work, fostering a mindset that prioritizes community well-being and environmental stewardship alongside technical proficiency.

Feb 1, 2025

By Gordon M. Pugh, David G. Rasmussen

INTRODUCTION The two unit operations in cut-and-fill stoping that would benefit most from increased mechanization are drilling blastholes and moving broken ore to the ore¬passes. Drilling in current practice is done with hand¬held jackleg and stoper drills. Broken ore is commonly moved from the face to the orepass by a small slusher. This type of equipment can be easily moved through the raises. Hand-held drills have a slow drilling rate and require one operator for each machine. Drilling can be done much faster by small jumbo-mounted machines as two or more drills can be operated by one miner. Load-haul-dump (LHD) units move broken ore from the face to one or more orepasses at a much faster rate with less loss and dilution than slushers. These units are mobile and may be used at more than one place during a shift. The problem which must be overcome in applying this higher degree of mechanization is the restricted means of access inherent in current practices. Cut-and¬fill methods are usually applied to mining veins that are narrow, irregular in dip and strike, or where ground con¬ditions require the support of sand fill. The mechanized equipment which is needed to accomplish high produc¬tion cannot be raised or lowered through raises without being disassembled. A jumbo which will give the desired performance would be mounted on a rubber-tired carriage with a diesel engine for propulsion. Twin hydraulic booms run by a small air motor would carry pneumatic drills. Over¬all dimensions of the unit would be about 8 m (26 ft) in length, 1.6 m (5'/z ft) in width, and 1.6 m (5'/z ft) in height. An LHD of the desired capacity would be rubber¬tired and either diesel or electric-powered. The overall dimensions of a 2.3-m (3-cu yd) unit will be about 8 m (26 ft) in length, 1.8 m (6 ft) in width, and 1.5 m (5 ft) in height. It will weigh about 12 700 kg (28,000 1b). It can readily be seen that conventional raises can¬not handle this size equipment. The most desirable means of access enables equipment to be driven into the stoping areas. Ramps can enter the stope by being driven upward in the vein walls or by being developed in the vein on top of the fill as the stope advances. This ramp system not only permits the use of rubber-tired equipment in multiple working places but also enables its removal for repairs without component breakdown. In the proposed method, as in conventional cut-and¬fill stoping, sand fill will replace the mined-out ore. By constructing an inclined timber floor at one end of the stope, a ramp can be maintained on top of the fill and advanced as the stope is advanced cut by cut (Fig. 1). The ramp is, therefore, developed during the stoping process and is only driven as a tunnel when rising over and around the sill and crown pillars. A stoping section consists of three blocks of different geometric shapes. The first and last blocks to be mined will be triangular in the plane of the vein, and the blocks between will have the shape of parallelograms (Fig. 1). The first block will develop the initial ramp by breast stoping and filling to the ramp floor (Fig. 2). The ramp will need to be completed through to the next level be¬fore stoping of the subsequent block can begin. The subsequent blocks are mined by back stoping with the next ramp being developed at the other end of that block (Fig. 3). The length of each subsequent block can be varied without changing the slope of the ramp. As the new ramp is developed, the previous ramp is filled along with the stope cut. Access up and down is maintained through the stope. The final block is again breast stoped as no new ramp will be developed at the end line for jumbo egress. Boreholes provide ventilation between levels as well as utility access. They can also provide a secondary escapeway for personnel during periods of development. These boreholes would be located about 3 to 4.5 m (10 to 15 ft) in the footwall and spaced about 183 m (600 ft) apart along the vein. The orepasses are spaced about 61 m (200 ft) apart in the vein. This spacing allows not only a short tram for the LHD unit but also provides surge capacity for the ore between haulage trains. These passes are raised from the haulage levels. As development progresses, the raises are driven through the sill pillar, and then car¬ried in the fill as stoping progresses. Ventilation and utilities can be maintained through an orepass when it is not needed for ore. The end line orepasses are intended for this purpose as well as for personnel emergency egress. Overall dimensions and criteria assumed to illustrate the ramp method of access in a highly mechanized cut¬and-fill stope are: haulage level spacing of 61 m (200 ft); ramp gradient of 17%; average dip of approximately 1.57 rad (90°); initial stope length of 358 m (1177 ft); subsequent stope length of 179 m (588 ft); average stoping width of 3 m (10 ft) ; sill pillar thickness of 3.6 m (12 ft); crown pillar thickness of 1.8 m (6 ft); bored raises of 1.5-m (5-ft) diam; and cribbed orepasses of 1.2 x 1.2 m (4 x 4 ft) through the sill pillar and 1.2 m (4 ft) square inside the cribbed portion. DEVELOPMENT The ramp access system lends itself well to conduct¬ing the several phases of development concurrently. Haulage Drifts and Raises The first development step will be to drive the 3 x 3-m (10 x 10-ft) haulage drifts above and below

Jan 1, 1982