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By Claude Boisjoly, Pierre de Courval, Don Nguyen

The Sainte-Marguerite-3 (SM3) hydro project, presently under construction, requires the excavation of an underground powerhouse and large water conveyance tunnels. This paper describes the planning of the project, main features of underground structures, excavation techniques and ground support.

Jan 1, 1997

By Andrew Hall

Many Latin American countries are facing a scarcity of water. As such, infrastructure decisions are quite different from those made in parts of the world that experience a positive water balance. In the latter case, the water treatment approach tends to be ?treat and discharge.? For Latin American regions facing the challenges that go with a negative water balance, the focus is on resource optimization and reuse. Historically, the water challenge has had a significant impact on economic development in Latin America, especially in sectors such as mining, where water usage is high. At the same time, countries such as Chile and Brazil are major development targets for mining and oil and gas operations. Given the water supply challenge, industry is increasingly turning to technologies and processes that maximize water recovery and reuse. With sulfide precipitation and ion exchange water treatment processes for example, it is possible to treat and recover more than 99 percent of water for reuse onsite. These technologies have been applied successfully in other regions of the world where water conservation practices are essential to economic survival.

Jan 1, 2012

By Peter Zhang, Todd Minoski, Gabriel Esterhuizen, Jack Trackemas, Berk Tulu, Morgan Sears

Roof stability in the belt entry is critical for safe and continuous production of coal during longwall mining. Previous studies of roof falls that occurred in belt entries have shown that the roof falls were largely associated with high in situ and longwall-induced horizontal stresses [1,2,3,4]. To properly support the roof in a belt entry, it is important to understand how longwall-induced horizontal stress changes can affect roof stability in the belt entry. Monitoring of horizontal stress changes was conducted in the belt entries of two Pittsburgh seam longwall panels oriented unfavorably to the major horizontal stress. Numerical models were also set up to investigate how horizontal stress concentrates and relieves in the belt-entry roof near the face as panel orientation changes. Both measurements and modeling results show that high horizontal stress concentrates in the belt entry roof within about 15 m outby the face. The study demonstrates that longwall-induced differential horizontal stress can be used to evaluate the horizontal stress concentration factors. The horizontal stress concentration factors change with panel orientation, resulting in high stress concentrations at orientations between 20 and 110° and low stress concentrations between 130 and 180°. Roof support strategies are given for the belt entries under the influence of high horizontal stress. For unfavorably oriented panels in weak roof conditions, supplementary support should be installed during development, and cable bolts should be anchored into a stable roof horizon. The bolting pattern should be designed to cover both entry corners and the entry center to prevent potential roof cutters and sagging.

Jan 1, 2023

By David J. Hatem

Tunnels and underground projects are inherently more risky than vertical projects, which typically utilize more conventional design and construction approaches and are undertaken in the context of relatively ascertained and defined conditions. On tunnel and under-ground projects, there are a host of special risk factors, including unknowns and uncertainties as to the physical and behavioral characteristics of the ground, the inextricable interdependence and necessary interaction of design decisions and construction means and methods with those ground conditions as well as the manner in which risks are allocated among project participants for un-anticipated subsurface conditions. Public-private partnerships (PPP) projects, in their own respects (and independent of any major subsurface component), pose significant risk for all private sector participants. The main driver of owners to procure projects using PPP is financial, as often all, or substantially all, of the design and construction risk are transferred to the private sector consortium, including the design-build (D-B) team. For a concerning number of those public owners, that risk transfer regime includes rather onerous and aggressive contractual terms that allocate to the private sector participants substantially all risks associated with the encountering of unanticipated subsurface conditions. These aggressive risk allocation provisions, while directly impacting project participants upstream of the consulting engineer, have an indirect and corresponding risk intensifying effect upon consulting engineer professional liability exposure. There are many factors that result in increased professional liability exposure for consulting engineers involved in PPP projects. The more prominent and prevalent of those factors fall into the following categories:

By James Humphrey

There is a natural resistance to change in any form. When it comes to implementing a game-changing technology like autonomous haulage on an operating mine site, the resistance can at times appear insurmountable. Whether based on real information or misguided preconceptions, it?s essential that we don?t underestimate the effort it will take to overcome this resistance, while clearly recognizing when it?s worth the effort. These realizations did not happen overnight for sites where autonomous haulage has been implemented. Nor did they happen overnight for manufacturers of autonomous mining equipment. Caterpillar, for example, began building toward autonomy more than 30 years ago and had a truck operating in the mid-1990s. Lessons learned during those early years led to the realization that there was much more to be learned ? not just about the machines themselves, but about the systems and knowledge that must be in place for a successful implementation. Working closely with customers, initiating real-life demonstrations on mine sites, having discussions with regulatory agencies and other stakeholders ? these and many other activities were necessary before autonomy could be fully and successfully launched. After decades of effort, Caterpillar?s first official commercial autonomous mine site went to work in 2011 in Farmington, NM.

By William Gleason

"Komatsu has been on the cutting edge of autonomous mining for the past 30 years and the company remains at the forefront of the technology that is changing from concept to a full-fledged reality.In 1996, Komatsu America Corp. (KAC) purchased a controlling interest in Modular Mining Systems; a move that enabled both companies to expand their product lines. It was through this effort that Modular helped to deploy the first autonomous haulage system (AHS) — the Komatsu FrontRunner system. In January 2008, the first commercial implementation of the FrontRunner system occurred at Codelco’s copper mine in Chile. Since then, Komatsu has put more than 130 haul trucks into seven sites on three continents to haul copper, iron ore and oil sands and its equipment has moved 1.8 Gt (2 billion st) of material with zero lost time incidents attributed to Komatsu’s autonomous trucks. The 1.8 Gt (2 billion st) is the most of any commercial mining autonomous haulage system and there is more to come. In November, Komatsu announced that an additional 150 autonomous haul trucks will be deployed to the Canadian oil sands over the next seven years.Komatsu has continued to pioneer autonomous haulage development, creating a range of autonomous options that includes semiautonomous and teleremote options all the way up to a haulage vehicle that stole the show at the world’s largest mining equipment trade show.In 2016, Komatsu advanced the concept of driverless haul truck to a new level when it displayed its Innovative Autonomous Haulage Vehicle (IAHV) at MINExpo in Las Vegas, NV. The concept vehicle is the first mega class haul truck designed to be fully autonomous, without an operators’ cab included on the vehicle.Unlike other haul trucks, the vehicle was developed exclusively as an unmanned vehicle designed to maximize the advantages of unmanned operation. Among other advancements, it was designed to distribute equal load to the four wheels, both when the vehicle is loaded and unloaded, and adopt four-wheel drive, retarder and steering. Komatsu said it is aiming for high-performance shuttling of this vehicle in both forward and reverse travel directions, thereby eliminating the need for K-turns at loading and unloading sites."

Dec 1, 2018

By Y. V. Vasylchuk

An algorithm is presented for optimizing the classification of surface mine material subject to excavating constraints. High-resolution, expected-profit models are optimized to classification maps subject to site-specific excavating constraints. This optimization problem defies traditional closed-form analytical solutions. A practical heuristic algorithm quickly determines the optimum final destination for material subject to realistic selectivity constraints. The expected profit could be calculated from an estimated model if the value calculations are all linear; otherwise, simulation could be used. In both cases, a single expected profit for all destinations on a high-resolution grid is the starting point for dig limits optimization. Maximizing expected profit in a risk-neutral manner is correct given the repeated nature of grade-control decisions over relatively short timeframes.

By Duane A. Smith

Introduction From the days of the Spanish in the eighteenth century, Colorado's San Juan mining district has attracted miners and public interest. The Spanish left behind names - San Juans, La Plata, Animas, legends of lost mines, and the remains of a few scattered mining operations. They came, but did not stay. Again in 1860-61, as a spinoff of the Pike's Peak gold rush, prospectors climbed the mountains and descended into the canyons searching for gold. They found some, not enough to convince them to remain and confront the isolation, often hostile environment and the Utes, who rightfully felt this to be their home. Not until the 1870s did miners come to stay. In their wake little camps grew in the high valleys and squeezed into narrow canyons. Nowhere else in Colorado were there more rugged mountains, a higher average elevation, nor a climate that one old Swede said was "three months of mighty late fall and nine months of winter." The San Juans proved eventually to be a mineral treasure chest. At the moment, however, the prospectors sought gold. Then they discovered silver deposits and the first rush was on. It got started just in time to be completely overcome by the Leadville excitement. At Leadville, investors almost fell over themselves to buy claims and stock in the hopes of becoming another millionaire like Leadville's own Horace Tabor. The San Juaners could only look from the sidelines and speculate how it might have been had fate been kinder. Fate was seldom kind, as these pioneers quickly discovered. From the mid-1870s on, the San Juaners wrestled with some major problems. And the fate of their district rode in the balance. The problems they faced were similar to those of other Colorado districts, compounded by their geographic isolation. Every mining district needed the best transportation system available, experienced investors combined with sound investment, and mineral reserves to develop. The San Juans offered the last in abundance. It was hoped the first two would appear. Railroads - much needed transportation link Nothing was more desired than railroad connections, the penultimate nineteenth century form of transportation. Colorado's own, the Denver & Rio Grande, resolved the issue with its mountain-hugging narrow gauge. As early as the mid-1870s, the D&RG dreamed of tapping this potentially lucrative market in southwestern Colorado. A national economic depression and then the Leadville silver excitement prevented immediate construction. Not until 1879-80 did survey crews start work.

Jan 2, 1988

By Robert Smith

Deposits are global, said Barrick Gold's Smith. This means that the mineral industry, by necessity, is global. "Manufacturers have considerable freedom to decide exactly where they wish to produce whatever it is that they sell," he said. "What we sell, on the other hand, must be produced where nature chose to lay it down. The question is not so much, whether to go global, as when to do it and how to go about it." The timing of international expansion depends on external factors, often political, Smith said, and on internal ones that relate to the company's size and stage of development. "In deciding how to expand, a company is largely deciding how to adapt its existing business strategy to activity on the world stage," he said Barrick entered 1997 with 1.58 kt (51 million oz) of reserves, Smith said, annual production of 93.3 t (3 mil- lion oz) and cash flow of $463 million. Reserves in- creased 40% in 1996 and production will begin to rise again significantly in 1999. "We believe our fundamental strategy is responsible for our early development and subsequent success," he said. Barrick entered the gold-mining industry in 1983. Its corporate mandate was to create shareholder value, Smith said. From the beginning, the company took a different approach - businesslike, entrepreneurial, strategic and focused. "Many mining companies start out with a technical team and develop business and financial expertise thereafter," Smith said. "In 1983, Barrick had the business people, and then moved into mining." First, it acquired part interest in two small operations, one in Alaska and one in Ontario. Then, in 1984, it merged with Camflo Mines, which operated a low-cost underground operation in Quebec.

Jan 1, 1997

The Global Mining Standards and Guidelines Group (GMSG) is building an international, multi-stakeholder community to advance the availability and use of standards and industry guidelines for the global mining community. Standards and guidelines are key strategic tools for operational excellence, enabling companies to move forward with efficient, innovative operations with reduced risk. Launched in May 2012, the GMSG is the first international center to bring together information, resources and collaborative projects for mining standards and guidelines, in an open, knowledge-sharing forum. The GMSG is supported by five partner organizations providing outreach and helping to guide GMSG activities: the Canadian Institute of Mining, Metallurgy and Petroleum (CIM), the Society for Mining, Metallurgy and Exploration (SME), the Australasian Institute of Mining and Metallurgy (AusIMM), the Southern African Institute of Mining and Metallurgy (SAIMM) and the Surface Mining Association for Research and Technology (SMART). GMSG was formed under the CIM Surface Mining Society, though its mandate extends to include underground mining as well. ?SME is supporting the GMSG as a key international activity to advance the implementation of standards and guidelines in our industry, and to provide a forum for our members to access, and contribute to, projects and information to assist their operations,? said SME Executive Director David Kanagy. ?We see the GMSG as a good example of ways the major mining associations can work together for the benefit of all our members.? The GMSG charter encompasses all standards and guidelines that apply to mining; however, a number of subject areas are now being spearheaded by six working groups, namely: ? Access and usage of data from mobile mining equipment onboard systems. ? Operational safety. ? Situational awareness (namely, a unified equipment operator interface). ? Underground operations. ? Asset management and operations data definitions and KPIs. ? Energy in communition.

Oct 1, 2013

The global mining industry will always face significant challenges. Some, though, are bigger than others. What do you consider the major challenges facing the mining industry as a whole and SME in particular? Without a doubt, the major issue in both coal and metal/nonmetal mining industries is the ?graying? of the workforce in all aspects of mining. As the baby boomers continue to age, valuable experience is being lost by industry, government and academia. And there is the potential for SME to lose some of its membership. Now with that said, I should note that, despite the aging of the workforce, SME membership continued to grow by 7.1 percent during 2011.

Jan 1, 2012

By Joel Lööw, Jan Johansson, Lena Abrahamsson

In this study, we try to illustrate what new technology can mean for the individual miner. We formulate the notion of Mining 4.0, where we attempt to create an image of how the future might look from a miner’s perspective and how mining companies might navigate their way to a future that works for all miners. 

By William Gleason

"Technology of all forms has experienced exponential growth in recent years, and there is no sign of it slowing down. This growth has presented amazing opportunity and significant challenges in nearly every aspect of daily life. Some of these changes are seen and experienced every day as we turn to our smart phones, tablets and smart watches to help with us with everything from directions to the store to managing our health. And other technological growth takes place far away from the public view but can have as much of an impact on our daily life as does shopping at Amazon or connecting with friends on social media.At the “THRIVE 2018, Innovations Advancing Mining” conference presented by SME on Sept. 27 at the Sheraton Pittsburgh Hotel at Station Square in Pittsburgh, PA, the focus was on innovation and how it affects the global mining industry.More than 100 people were on hand for the inaugural event, and they were treated to a unique program that focused on the cutting-edge innovations that will carry the mining industry into the future while increasing safety and productivity along the way.2018 SME President Barbara Arnold was the driving force behind the conference and put together the technical program with a focus on innovation through the entire mining life cycle and into the future. Talks ranged from more efficient and safer ways to extract minerals to some of the most advanced end uses of minerals and metals, including the use of 3D printing to create precision parts for machines and humans from advanced metal alloys.“We need to adapt new technologies to our industry and develop additional technologies as we provide materials and metals for infrastructure and energy development in the United States, around the globe, and to the Moon and beyond,” Arnold told Mining Engineering. “Our inaugural THRIVE conference sets the stage for these innovations to be applied and to continue to be developed. Our mining industry can only continue to thrive with these advances.”"

Jan 11, 2018

By Tetsuji Hirato, A. J. Monhemius, Yasuhiro Awakura, G. W. Warren, E. Peters

An electrostatic pseudo-liquid membrane technique, in which extraction and stripping take place simultaneously in a single reaction vessel using an electrostatic dispersion, was applied to recover Ni(II) from aqueous 0.1 kg m-3 Ni(II)(as NiSO4) – CH3COONa solutions, and the Ni(II) ions were concentrated by a factor of 9 into an aqueous 1.0 kmol m-3 HCI solution using D2EHPA as an extractant at the applied voltage of 3.7 kV for the dispersion. When the process of ESPLIM proceeds favorably, the concentration of Ni(II) in the upper part of the organic phase of the reaction vessel is lower than that in the lower part. In addition, the concentration of Ni(II) in the organic phase of the extraction chamber is higher than that in the stripping chamber. For the stable operation of this process, the stripping rate must be greater than the extraction rate to prevent the excess accumulation of Ni(II) in the organic phase which leads to the poor dispersion of the aqueous phase.

Jan 1, 1993

By William Gleason

"In a time that seems to be dominated with nothing but bad news coming from the mining industry, there is a success story that has been quietly happening in Southwestern Wyoming for more than 60 years, and it is one that is likely to continue for many decades to come.Beneath the wind swept high desert plains of Sweetwater County, WY, about 32 km (20 miles) west of Green River, lies the Green River Basin where five companies, including Tata Chemicals North America (TCNA), are mining the world’s largest known deposit of trona and, in turn, are collectively producing 15.3 Mt/a (17 million stpy) of soda ash.“We have a long-term growth story that has been, and will continue to be a steady earner for many years to come,” said J. Martin Keighley, managing director of TCNA who has been in charge of the mine, formerly known as General Chemical Industrial Products Inc., for Tata Chemicals for about three years.According to the U.S. Bureau of Land Management (BLM), Keighley is safe with his prediction of future success. The BLM estimates that there are enough reserves in the Green River Basin to last another 2,000 years. Currently, four trona beds in the Green River Basin are being mined and in all, there are 25 major trona beds that occur within the Wilkins Peak Member of the Upper Eocene Age Green River Formation. The trona deposit as a whole covers about 2,500 km2 (1,000 sq miles) within the Green River Basin.And imagine, this economic mainstay in the region was discovered accidently.Prior to 1948, soda ash, the salable commodity that comes from trona and is used in a host of products including glass and detergent, was produced synthetically. In 1938, an oil and gas exploration team working in the Green River Basin came away with a find that would change the soda ash industry and the physical and employment landscape of southwestern Wyoming forever. Within 10 years, the communities of Green River and Rock Springs, which were built largely on the back of coal mining and railroads, had another commodity beneath their feet."

Jul 1, 2016

By Liz Diaz, Tacio Ferreira

Capstone Copper’s Pinto Valley Mine faced challenges in recovering rock and ore on final walls because of geotechnical constraints that require restrictions on methods for loading blastholes adjacent to the pit boundaries to preserve wall stability. The operation had been using the same drill and blast designs for years. With changing geology, such as harder rock, as mining progressed, material was being left unmined in final walls because of poor breakage. The amount of unrecovered, unprocessed ore was estimated at approximately 380,000 tons a year generated from an average of 60 final wall blasts performed annually. The engineering team from Capstone and Dyno Nobel engaged to minimize the amount of material left on the final pit walls. This paper presents how we collected data, reviewed design standards, and found opportunities to improve ore recovery from pit final walls without increasing drilling and blasting costs. The results collected from implementing the new design on two benches showed the potential for extra revenue of approximately $3.6 million generated annually from reducing final wall unrecoverable underbreak by nearly 71% on the mine’s highwalls.

Feb 1, 2025

By Alejandro Sanz Garrote, Juergen Laubbichler, Fernando Triana Gracian, Paz Navarro Gancedo-Rodriguez, Andreas Feiersinger

The Combined Sewage Storage Tunnel (CSST) is part of the Ottawa River Action Plan and will greatly reduce the frequency of sewage overflows into the Ottawa River during storms. The project consists of the design and construction of two TBM tunnels running EastWest (EWT) and NorthSouth (NST) along 6.2 km in total, and multiple shafts and support buildings. Contractor Dragados Tomlinson JV (DTJV) was awarded the 169 million CAD construction contract in 2016 and the CSST will be in operation in 2020. Dr. Sauer & Partners (DSP), supported by Intecsa-Inarsa, was responsible for the detailed design of the precast concrete tunnel lining as well as the geotechnical risk management program. This paper addresses TBM selection, critical tunnel sections, geotechnical risk management and rock mass grouting as a geotechnical risk mitigation measure. Successful collaboration of Owner, Owner’s Engineer, Contractor and Contractor’s Engineer led to a safe and cost-effective design and construction

Jun 13, 2021

"History - How did you get into mining and involved with SME?Unlike many past presidents, I do not come from a mining lineage. I liked math in high school and believed I wanted to be an engineer. I told my math teacher that, and he laughed in my face. I believe that humiliation is what carried me through engineering school. At the time my ability to go to college relied on how inexpensive I could make it. My brother told me that there were a lot of scholarships in mining engineering, and I should apply to mining schools. As usual, he was right and I was off to the University of Idaho to study. My first summer break I got a job with Hecla at a mine in Arizona. I was a laborer on a shotcrete crew. I knew after the first summer that I loved underground mining, and I never considered changing disciplines. Looking back, I was working in miserable conditions (hot, humid), on a miserable job (shotcrete), where I got injured, and two summer student roommates died in a car accident on the commute home after work. I had every reason to hate the industry, as I had seen virtually everything bad about what we do. But I didn’t, I loved it. I said I was good at math, I never said I was smart.I joined SME in college because I was told to by the head of the mining school, Dr. Jack Hoskins. You did what Jack told you to do. I got involved because I went to an annual meeting and the papers in the underground sessions were terrible. I refer to bad papers as the “Tensile strength on cable bolts in sub-arctic regions on Tuesday” papers. Real snoring fodder. I don’t remember who I was complaining to, but they told me to quit my grumbling and fix it. So I chaired a session, and tried to get only good quality papers, something that has been my mantra for years with the Mining & Exploration Division. I also volunteered to help the local sections too. Then one day I woke up as president.What is your opinion of the health of the mining industry?The mining industry is in bad shape. Coal is under attack and will likely never recover to its former greatness. Our President has banned new coal leases, and the state of California is forcing people it does business with to divest their interests in coal companies. And that all happened in just in a few short weeks this January. Usually in America you get a trial before you are given a death sentence, but not with coal."

Jan 1, 2015

By Isabel F. Barton, Christian A. Rathkopf, Mark D. Barton

Rhenium (Re) is one of the rarest elements on earth and is a designated critical element in the United States and European Union for its uses in superalloys. Unusually among critical elements, Re is produced entirely as a byproduct of molybdenite (MoS2) mining, as pure Re minerals are extremely rare. However, Re concentration in natural molybdenites varies from a few parts per trillion to tens of percent. There are few known consistent patterns and no firmly established reason for this variation, making it difficult to use molybdenite Re content as a proxy for metal grades, a vector to high grades, a clue to the geological and geochemical nature of the ore deposit, a guide to overall Re resources or for any other of the applications that have been suggested for it over time. 

By William Gleason

"The mining industry tends to focus on very large numbers, whether it’s talking in terms of size of deposits, tons of material mined, the equipment used or the dollars spent. The numbers associated with mining projects are often in the hundreds of millions, but sometimes it’s the little things that can have the biggest impact.Take, for example, the Rosemont Copper Project in Arizona. Owned by HudBay Minerals, the Rosemont Copper project, when in production, is expected to be one of the largest copper mines in the United States, accounting for about 10 percent of total copper production with annual production expected to be 110 Mt/a (243 million lbs/year). However, the project is currently mired in a years-long permitting process. At the 2017 SME Arizona Conference in Tucson, AZ, Kathy Arnold, director of environmental and regulatory affairs for Hudbay Minerals, spoke about the project and the efforts to get it into production.She opened her presentation with the unfortunate news that her 2017 presentation would not be that much different than the 2016, 2015 or 2014 presentations she gave to the same conference. That’s because, as of Dec. 4, 2017, the project had been in the permitting process for 3,797 days, more than 10 years. The process began when Rosemont submitted its initial mine plan in 2006 and a revised one in 2017. The official start to Rosemont Copper’s National Environmental Policy Act (NEPA) started in 2008.In June 2017, the project received its Final Record of Decision from the U.S. Forest Service, moving it a step closer to production. Yet it still faces stiff opposition from opponents while it works to secure the Clean Water Act Permit from the U.S. Army Corps of Engineers and to complete its final mine plan of operations.In her presentation, Arnold said the long process taught her many lessons, including approaching things with a different mindset. More than 130 pages worth of public comments have been collected over the years. The concerns expressed range from lighting issues to pavement to preserving land for a jaguar that was spotted on the property and named El Jefe.“A lot of things that people worry about seem to be small things, but we had to have a different mindset and be open-minded to the concerns,” Arnold said. “That is the commitment we made.”"

Jan 1, 2018