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By William Gleason

The mining industry is under immense pressure to not only meet increasing demand for minerals, but to do so in an environmentally safe and sustainable manner. Growth in electric vehicles, battery storage, renewable energy infrastructure and data centers to power artificial intelligence (AI) has led to an unprecedented demand for minerals such as copper, lithium, rare earth elements and others. The need for these minerals for national defense has only increased the pressure on the mining industry. Increased geopolitical tensions between the United States, China and Russia has added a sense of urgency as supply chains have become a focal point for the U.S. Department of Energy (DOE) and Defense (DOD) and other government agencies. The International Energy Agency (IEA) predicts that copper demand is expected to grow by 50 percent by 2040 while demand for lithium could increase eight-fold by 2040 and demand for nickel and cobalt could double. The challenges to meet the increased demand include technological, workforce, exploration and environmental issues. From Feb. 22-26, the global mining industry will converge on Salt Lake City, UT for the MINEXCHANGE 2026 SME Annual Conference & Expo where these challenges and others will be addressed by some of the leading minds in the industry. Included in this year’s conference is the Resilient Energy in Mining Symposium, a symposium with input from across SME that looks to address some of the most significant challenges the industry is facing. “Adopting environmental, social and governance (ESG) best practices has become a necessity for the mining industry, not an option. The Resilient Energy in Mining Symposium is crucial for MINEXCHANGE 2026 because it addresses the complex challenges of transforming traditional mining operations to support a sustainable and secure energy future,” Lisa Gonzales, principal engineering at Arcadias and MINEXCHANGE 2026 SME Annual Conference Chair and chair of the Resilient Energy in Mining Symposium said. “Mining is inherently energy-intensive, yet it is also foundational to the global energy transition, supplying the critical minerals needed for renewable technologies. By bringing together industry leaders, the symposium fosters collaboration and actionable change, showcasing advancements and real-world solutions that demonstrate the tangible benefits of resilient energy strategies. This unique forum enables knowledge sharing, inspires innovative thinking, and helps set the standard for sustainable practices across the sector.” The symposium was created in direct response to a SME member survey in 2023 conducted by the Responsible Mining and Underground Construction (RMUC) Strategic Committee. “The survey highlighted a strong demand for technical resources on energy transition, carbon reduction, renewable power, climate change, and ESG reporting,” Gonzales said. “To address this, I collaborated with RMUC to engage committee members from all SME Divisions, ensuring a diverse and comprehensive platform that reflects every aspect of mining. We intentionally structured the symposium to centralize key content and minimize duplication across divisions.”

Jan 1, 2026

By Todd Burchett

Mining engineers spend countless hours and resources when designing a new underground coal mine. Their primary objective is to design the safest and most efficient operating mine with regards to coal production. A key variable often overlooked in this design stage is the slope conveyor. Typically, a slope conveyor is expected to operate with a 98-percent or higher availability. However, too often little effort is put forth by the mining engineer to optimize its design. Coal companies will rely on engineering, procurement, construction and management (EPCM) companies for the preliminary design, because the slope conveyor will be considered part of the surface material handling processes. This preliminary design will be used when soliciting quotations for the slope conveyor. Unfortunately, EPCMs may not have enough expertise with conveyors to optimize the design. This expertise is available with an original equipment manufacture (OEM) of conveyors, which ultimately may be responsible for supplying the slope conveyor. Each OEM will provide a bid package that represents what it considers to be the optimal design.

Jan 1, 2013

The 29th annual American Mining Hall of Fame Awards Banquet and Fundraiser sponsored by the Mining Foundation of the Southwest (MFSW) will be held at the JW Marriott Star Pass Resort, Tucson, AZ on Saturday, Dec. 3, 2011. Each year, one living inductee, two recipients of Medals of Merit, and up to five honorees from mining history are chosen by the MFSW for their outstanding contributions to the mining industry. Chilean Minister of Public Works and former Minister of Mining, Laurence Golborne Riveros will be the guest of honor, featured speaker and inductee into the American Mining Hall of Fame. Golborne Riveros was instrumental in managing the rescue of the 33 Chilean miners in October 2010 and in the coordination/management of the ?townsite? for family members, rescue support and the media. His engineering background and executive management skills made him ideally suited to assist in both a technical and managerial role in this emergency.

Jan 1, 2011

By C. L. Wilsey, K. M. Oakes, W. J. Reich, M. J. Protani

The time frame required to complete the National Environmental Policy Act (NEPA) process for a new mine or the expansion of an existing mine can range from nine to 24 months, or even longer. The time frame will vary depending on whether an environmental assessment (EA) or an environmental impact statement (EIS) will be completed Completing properly designed baseline studies to collect natural resource data to support the EA or EIS prior to the start of the NEPA process can shorten this time frame. In this paper, a two-year natural resource baseline study by Homestake Mining for the Ruby Hill Mine, Eureka County, NV, is used as a case study to describe how a properly designed and executed natural resource baseline study streamlined the NEPA process.

Jan 1, 2003

Evver since it first displayed an autonomous mining truck at the 1996 MinExpo show in Las Vegas, NV, Caterpillar has been building the blocks to a fully autonomous mine. In May, the company unveiled another block in that progression, the new Cat MineStar System that it says is ?the industry?s broadest, most comprehensively integrated miner operations and mobile equipment management system.? The full system is comprised of five capability sets ? Fleet, Terrain, Detect, Health and Command ? to help operators define the size and scope of their management system based on the needs of their mining operations. Michael Murphy, technology and autonomy manager for Cat Global Mining, explained that the customers were not ready for an autonomous mining truck in 1996, but that many customers wanted the building blocks to eventually get to autonomous mining. After 15 years of work, Murphy said the building blocks have come together in the form of the Cat MineStar System.

Jan 1, 2011

By Gino Vogt

In mechanized tunnelling operations performance, consumption and safety are main factors for jobsites. One of the most important components effecting these factors, especially in slurry TBM operations, are Slurry Treatment Plants (STPs). Inadequate/ suboptimally dimensioned and designed STPs create bottlenecks for tunnelling operation and jeopardize time schedules and performance. Inefficiently planned STPs could drastically increase consumption figures such as electrical power, bentonite, water and polymers, etc. Inaccurately selected and treated suspension properties can cause a high-risk potential for the whole job. This paper debates the relevant key parameters for STPs from start to finish of a project and its results in influencing factors from the manufacturer´s point of view.

Jun 13, 2021

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

By Lauren M. Roberts, Ralph R. Sacrison

Pipeline or borehole free-fall transfer of material has long been done in support of underground mining. This paper addresses some characteristics and design elements in selecting systems suitable to the transferred media and the mine requirements. Though aspects of overall systems are discussed, principal attention is directed to the slickline/dropline/transfer line and the discharge diverter/rockbox/energy dissipator/boot. These terms are common to these systems, often used interchangeably, and will be used as appropriate to the material, equipment and construction. Following several design sections, fabrication and construction, and system operating and maintenance procedures are discussed.

Feb 1, 2025

By Dapeng Zhang, Brij Moudgil, Shibo Zheng, Chunhui Feng, Wenyi Song, Wending Xiao, Patrick Zhang

The separation of dolomite from phosphate is the most challenging problem in phosphate mineral processing. More than 50 percent of the phosphate reserve in Florida contains too much dolomite to process using current industry practice. The current way of producing phosphoric acid requires less than one percent MgO in the phosphate concentrate as the feed material. The Florida Industrial and Phosphate Research (FIPR) Institute has collaborated with worldwide experts in the field to address this issue. As a result, the industry is now offered three feasible options. Option I entails three methods for reducing MgO content in the concentrate from the Crago process, including adding a dolomite depressant in the rougher flotation step, dolomite flotation of the cleaner concentrate, and scrubbing the cleaner concentrate in quartz sand, which could reduce MgO content in the final concentrate by 20 to 40 percent. Option II involves the crushing and grinding of high-dolomite phosphate pebbles followed by dolomite flotation at slightly acidic pH using a new collector that does not require phosphoric acid as a phosphate depressant, achieving a final concentrate analyzing less than 0.9 percent MgO at about 87 percent P2O5 recovery. Option III is a gravity separation technique using an innovative separation jig, and its full potential remains to be demonstrated.

By Art Hamid, Manfred Wong, R. John Caulfield

"The proposed Channel Tunnel is a critical component of the San Francisco Public Utilities Commission’s (SFPUC) Central Bayside System Improvements Project (CBSIP), which is a key element of a $6.9-billion sewer system improvement program to upgrade its aging and seismically vulnerable wastewater facilities. The tunnel will provide gravity conveyance and storage of combined sewage flows from the northeast sector of San Francisco, CA to the Southeast Water Pollution Control Plant for treatment. The tunnel will be approximately 2.7 km (1.7 miles) long and 7.3 m (24 ft) in internal diameter. It will utilize a single-pass precast concrete segmental lining system. Tunneling challenges include excavating with pressurized face tunnel boring machine (TBM) technology through highly variable ground conditions including the Franciscan Complex (rock and mélange), clayey/silty sands, stiff to hard clay (Old Bay Clay) and mixed-face conditions. The project will also require several deep shafts that will be technically challenging. Project backgroundThe SFPUC is a department of the City and County of San Francisco, CA that provides municipal power, drinking water and wastewater services to San Francisco.San Francisco’s combined sewer system collects both wastewater and stormwater in the same sewers, which is then pumped, treated to stringent state standards and discharged into the San Francisco Bay and Pacific Ocean. The sewer system includes tunnels, large storage/transport boxes, 1,600 km (1,000 miles) of collection sewers, 28 pump stations and three wastewater treatment plants. After decades of service, much of the system is nearing the end of its useful life.The existing system is also vulnerable to seismic damage. During the 1989 Loma Prieta earthquake, damage to SFPUC wastewater infrastructure was extensive. This included the 3,415 m (11,200-ft) long, 1.7m (66-in.) diameter Channel Force Main, built in 1976, and a critical component of the conveyance system. The Channel Force Main carries 70 percent of the bayside dry weather sewage flow from the northern and central part of the city to the Southeast Water Pollution Control Plant for treatment. It is antiquated, not pile-supported and not constructed to current seismic codes. There is also currently no conveyance redundancy for north/central bayside flows to the treatment plant. Figure 1 shows the SFPUC’s wastewater collection system, the existing Channel Force Main and the project location."

Jan 5, 2017

By Christopher J. Bise

INTRODUCTION Face haulage in underground mines and pit haulage in surface mines are the principal domains of rubber- tired haulage vehicles. In underground mines, cable- reeled or battery-operated shuttle cars and diesel-powered load-haul-dump vehicles are used; trucks are primarily used in surface mines. Although many concerns go into the selection of rubber-tired haulage vehicles, such as clearance and tire life, the most important factor from a mine-planning standpoint is the production capability of the vehicle in the mine environment. Therefore, this chapter will address this topic. UNDERGROUND FACE-HAULAGE VEHICLES The selection process for underground face-haulage vehicles is, in some respects, much simpler than that of the other haulage systems discussed to this point. It is simpler because these vehicles, which transfer the mined material from the face to the intermediate haul¬age system, are manufactured in various size ranges to cope with the confinement of underground opening widths and heights. However, since these vehicles oper¬ated in an intermittent fashion in conjunction with a constantly advancing face, the system's lack of perma¬nence and overall dynamic nature create a more diffi¬cult situation for predicting productivity. The emphasis in this section will be on prediction of productivity. There are three fundamental steps that must be taken to analyze the productivity potential of any face¬haulage system: l) Recognize the geologic (seam thickness, etc. ) and mining (opening widths, etc.) constraints that affect the velocity/clearance aspects of the haulage equipment, and select equipment from manufacturers' specifications with these con¬straints in mind. 2) Secure the elemental times of the face-haulage system. 3) Incorporate the elemental times into an accepta¬ble mine plan. By recognizing the geologic and mining constraints that affect the system layout, parameters, such as vehi¬cle payload, tonnage to be hauled per cut, and haulage distances, can easily be determined. Elemental times can be developed in two ways: 1) In an existing operation, a time study of the dynamic system can be conducted by placing three time-study engineers at the following static locations; (1) near the loading machine, (2) near the change-out point outby the face, and (3) near the dump. By synchronizing their watches and recording the actions of the haulage vehicles at these three locations, their time studies can be reduced to provide elemental times, such as vehicle tram rates (empty or loaded), vehicle discharge times, and loading rates. 2) In the absence of an existing operation, average values for the elemental times can be provided from other mines operating in similar condi¬tions, or by the manufacturers themselves.

Jan 1, 1986

By Sanja Zlatanic, Michael P. Della Posta

New York State’s Metropolitan Transportation Authority (MTA) has undertaken the largest transportation project in New York City. The East Side Access Project (ESA) will introduce MTA’s Long Island Rail Road (LIRR) service to the East Side of Manhattan, to a new terminal located beneath the existing, landmark Grand Central Terminal(GCT). Construction of the Manhattan Segment of the project will affect overlying operating facilities of two other MTA entities, Metro-North Railroad (MNR) and New York City Transit (NYCT) and major Midtown Manhattan buildings. The paper describes the evolution of the GCT concept at Manhattan from a shallow alternative proposed by a Major Investment Study (MIS), that would require extensive underpinning of multi-story buildings and have considerable impact on MNR and NYCT operations, to a deep alternative with lesser risk and potential for disruption.

Jan 1, 2001

By C. L. Lin

A PC image-based on-line coarse particle size analyzer has been developed to measure particle size distributions under plant situations where overlapped particles are being transported on a moving belt conveyor. Although previous testing had shown satisfactory performance of this image-based system for separated particle size measurements (the non-overlapped case), it was necessary to modify original algorithms in order to solve the overlap problem and make the system suitable for plant operations. On-site testing has been conducted at a large copper concentrator in the southwestern U.S. for further investigation of the overlap problem.

Jan 1, 1995

By David Mast, Irwan Halim, Brian Hagan, Kaveh Talebi, Jason Edberg, Amanda Foote

On June 14, 2023 Jay Dee Contractors’ Tunnel Boring Machine (TBM) “Phoenix” holed through and completed mining the second drive of the I-75 Segment 3 Storage and Drainage Tunnel. Completion of the tunnel came only after overcoming several challenges, including a groundwater intrusion event which deposited thousands of cubic yards of wet ground material into the tunnel. This paper will discuss the events which delayed completion of the tunnel by over nine months, the risk management and construction approaches assumed by the Design-Build team during bid, several challenges faced by Design-Build teams when building stormwater resilience tunnels using traditional Department of Transportation standards, and recommendations for improving risk allocation and proposal documents for future similar Design-Build tunnel projects.

Jun 23, 2024

By P. Somasundaran, H. S. Hanna

The separation of minerals such as apatite and scheelite by flotation from other salt-type minerals such as calcite is extremely complex owing to the close similarity between their physicochemical properties. In this paper, properties relevant to flotation such as crystal structure, solubility, surface charge and adsorption behavior of important salt-type minerals are examined along with the role of inorganic modifying agents such as silicates and polyphosphates and organic modifying agents such as starch and tannin. Flotation characteristics of these minerals are then reviewed and selected separation problems involving salt-type minerals are discussed.

Jan 1, 1976

By VIVEK KUMAR HIMANSHU, PK SINGH, AK MISHRA, MP ROY, RAVI SHANKAR

Underground blasting has many challenges. The primary aim of blast designers is to optimize drilling and blasting parameters to deal with the associated challenges. Optimizing these parameters is currently based on various rules of thumb, which have many site-specific limitations. Accordingly, computation of these parameters using empirical rock fragmentation predictors can be useful for blast designers. This paper presents the results of work on burden-spacing determination by back-calculation from the empirical Kuz-Ram model for underground stope ring blasting.

By K. W. Grubaugh

The recently enacted federal surface mine law (P.L. 95-87) will increase further the complexity of securing a reclamation permit. This law intensifies the need to present the required reclamation plan in a thorough and comprehensive manner. One plan format, that used in construction performance contracts, offers promise of filling this need. Reasons for using the format of expressed, bilateral, negotiated contracts common to the contruction industry, and the salient aspects of an application which uses this format are reviewed. Advantages of this procedure are seen to be improved mine planning, awareness of the total design job, potential for improved speed of permit acceptance and improved cost control.

Jan 1, 1978

By Charles A. Beasley, Vince Joyce, David E. Beasley, Orlando A. Gallegos, David A. Shuman, Mehmet H. Erten

COAL CHARACARISTICS AND PREPREPARATION REQUIREMENTS Preparation and Market Specifications The national ambient air quality standards (NAAQS) established by the Environmental Protection Agency in 1977 require that when coal is burned, the environmental degradation should be a minimum. For this reason, even coal containing low ash and sulfur must be used in compliance with the NAAQS. The most important pollutants resulting from the combustion of coal are ash, SO2, and NOx gases, and the particulate matter escaping with the combustion gases. The ash is the residue left after complete combustion of coal. It results from the inorganic mineral matter existing in the coal before it is burned. The SO2 results from the combustion of inorganic and organic sulfur associated with the coal. The inorganic sulfur may occur as pyrite, marcasite, or as sulfate sulfur of mostly iron and calcium. The authorities disagree in the definition of organic sulfur in the coal. However, according to ASTM Standard D2492-77,1 the organic sulfur is that sulfur occurring in the coal after subtracting the sum of pyrite and sulfatic sulfurs from the total sulfur in the coal. The NOx gases are produced from high temperature oxidation of nitrogen in the coal that is released into the atmosphere. The particulate matter may consist of fly ash and unburned coal. Selective Mining The cleaning of coal from included ash and sulfur-bearing materials should start at the working faces of surface or underground mines. This can be done by (1) mining only those seams which meet certain quality standards, (2) not mining sections of the seams which may cause deterioration in overall quality of the mined coal, and (3) using a mining method that allows selective mining of coal areas or horizons either underground or on the surface. Since these steps improve the coal quality before the coal reaches the preparation plant, they can be considered to constitute precleaning of coal. During the exploration and development stage of a mine, core and channel samples taken from the coal seam are used to determine (1) petrographic analysis and physical properties,2 (2) character of roof and floor of the seam, 3,4 (3) character and quality of impurities,5 (4) proximate and ultimate analysis, and (5) washability characteristics. However, all of these parameters are subject to considerable variation even within the same seam during the advance of the coal face. This creates a problem in meeting the market demand for coal quality if the coal is to be shipped directly from the mine. If the mining operation is large enough, special blending silos or mechanical blending systems may have to be used to provide uniform quality to the market. However, even if the coal is shipped from a coal preparation plant, prepreparation

Jan 1, 1991

By K. E. Burgher

Since World War II, the need for the use of explosives in construction, mining, and quarrying near congested urban areas has increased dramatically. Often times a coal mine, once isolated from a city, finds itself surrounded by residential and commercial structures. The United States Bureau of Mines and others have researched blast design to a point where ground vibration and airblast damage can be avoided. A problem still exists, however. It is the fact that people often react to only the loud noise associated with a blast although it may not cause damage. Most often it is the concussion of a blast, less than 20 hertz and inaudible, that produces damage. Public fear from the "startle" and "fright" of loud blast noise greater than 20 hertz leads to the complaints which are generally unfounded. See Thackray, Touchstone, and Baily (1975) for a further discussion of the startle effects of loud sudden noises. When blasts are designed in accordance with U.S.B.M. specifications, management generally has little to worry about with respect to damage claims. Complaints, however, still arise when the noise is accentuated from the blast. It is meteorological conditions which dictate how the sound levels will propagate. Some mines use small pilot test shots (generally one-two lbs) to determine when atmospheric conditions favor sound travel.

Jan 1, 1987

By David A. Milligan

This paper describes the Darwin Silver Recovery project, located 66 km (40 miles) outside of Lone Pine, near Darwin, Inyo County, California. A lead-zinc mine and a flotation concentrator were operated there from 1945 to 1957. By the time the mine was shut down, 1.53 Tg (1.69 million short tons) of tailings had been stored in ponds. An average silver assay of 47 mg/kg (1.38 troy oz/st) of tailings stimulated interest for commercial silver recovery. A heap leach process was developed in 1981 at the Tucson Research Center of Anaconda Minerals Company, a division of Atlantic Richfield Company. Agglomeration techniques were used on the ore since the fine grind did not allow direct heap leaching. Lime and cement were required as binders, Early laboratory tests showed that recoveries equal to those from an agitated leach could be achieved at lower capital and operating costs. Laboratory tests determined cyanide requirements, lime and cement usages, and percolation or leach rates, as well as confirming that a zinc precipitation step could recover the silver from the leach solution.

Jan 1, 1983