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By Joseph Sopko, Xavier Lacourse-Dontigny

For the REM (Réseau Express Métropolitain) project, a 2500 m tunnel was built using a tunnel boring machine (TBM) under the Montreal Pierre Elliott Trudeau Airport (ADM). Although the geology under the Montreal Airport (ADM) would have been suitable for an excavation with a hard rock machine, the rst section reuired an earth pressure balance (EPB) TBM due to the soft soil located under wetlands. After excavating 280 m, the TBM was blocked in a transition zone of unconsolidated, water-bearing soils directly above the underlying bedrock. A free air intervention was not possible due to these geological conditions. After several failed attempts to create a slurry cake for hyperbaric interventions, a ground freezing system was designed and implemented, incorporating angled pipes drilled from outside the wetlands to directly in front of the cutterhead. This paper discusses the engineering reuired to form a frozen, water-tight zone in front of the cutterhead using liuid nitrogen. It also describes the complex method of replacing the disc cutters while holding the ground freezing system active in a manner protecting the health and safety of the workers.

Jun 23, 2024

By D. Marcus

A methodology was developed wherein. the increase in compressive strength, mineralogical changes and pore water composition were all studied simultaneously as a function, of moisturized spent shale curing time. From these results the relationship between the nature of cementation process and the composition of pore water was established. Heavy metals were entrapped in the cementing constituents and the pore water became mainly a solution of alkaline sulfates. While the specific data are applicable only to the material studied, the methodology and general conclusions are useful for evaluating the environmental factors in spent shale disposal and expected leachates composition.

Jan 1, 1984

By Rajat Gangrade, Haotian Zheng, Jarrett Smith, Daniele Nebbia, Mike Mooney

The application of artificial intelligence (AI) to improve tunnel boring machine (TBM) operations requires a significant amount of information to train robust performance prediction models, e.g., for tunneling-induced settlement, productivity, tool wear, etc. This paper presents the AI framework applied to the North-East Boundary Tunnel (NEBT), the largest component of the Clean Rivers Project in Washington, DC. The paper focuses on required elements for real-time AI use to estimate tunneling-induced ground and building deformation and cutter tool wear. Keys to the framework include defining the necessary quantities of data required as well as the process of windowed training, validation and model testing. To date, the models developed for ground deformation and tool wear show satisfactory performance when compared to observed field observations during tunneling.

Jun 13, 2021

By Joseph L. Condon

The U.S. Department of the Interior, Bureau of Mines, is doing research on methods to obtain premining information on problems such as detection of old mine workings, abandoned oil wells, channel sands, faults, and other geologic features that are undesirable from a production or safety aspect. Techniques being developed to acquire the necessary information include seismic and electromagnetic. The seismic methods include high-resolution seismic and acoustic methods applied from the surface and inseam channel waves applied under- ground. The electromagnetic, or radar, methods are applied from the surface, from boreholes, and from the working face underground. All of these methods are useful under certain site-specific conditions, but none of these methods is universally applicable for all mining conditions.

Jan 1, 1980

By Gennaro G. Marino

This paper summarizes and evaluates data on mine subsidence ground movements and associated damage for houses in Illinois. Based on the data collected, the response of homes to subsidence ground movements is expressed in terms of repair costs. A damage criteria is then proposed that relates the ground movements and damage levels. The data were collected as part of a comprehen¬sive study performed for the Illinois Abandoned ?Lined Lands Reclamation Council, A -M-RC, by the Civil Engineering Department at the University of Illinois, and probably will be published in late 1934 by the council. The study concentrated its efforts on surface ground movements and the effects to houses over abandoned room and pillar mines. The resultant surface subsidences are commonly dish or bowl shaped and are termed sags. Method of Analysis The steps in analysis used to arrive at the proposed damage criteria are: 1. Canvas and rap subsidence damage in houses, 2. Assess the associated ground movements, 3. Estimate the damage repair cost, 4. Develop a damage/repair level classifica¬tion, 5. Correlate the associated ground movement, damage/repair level and home construction type, 6. Propose a damage criteria.

Jan 1, 1984

By Efstratios Karampinos, John Hadjigeorgiou, Philippe Morissette

"Ground support is a critical element in maintaining the stability of mining drives in deep and high stress mines. In challenging ground conditions, it is necessary to continuously explore ground support strategies that can control the resulting large deformations. It is an objective of mining operations to optimize the ground support by selecting appropriate systems at the time of installation of each reinforcement element. A successful ground support strategy will result in the use of a system that ensures both the structural and operational integrity of the excavations and mitigates the need for rehabilitation.Preliminary ground support design is often based on empirical observations and methods. Once a design is implemented, field trials, observations and in situ pull tests are used to fine tune or improve the design. Although not often employed during this process, numerical modelling can provide helpful insights into the impact of different ground support strategies. In this respect, it is possible to explore the use of multiple options before selecting the most promising ground support system for implementation in field trials. The challenges associated with the numerical modelling of rock support for mines have been described by Lorig and Varona (2013) and Potvin (2017). The employed numerical models should capture all potential failure modes of reinforcement throughout the mining sequence of the excavation. In particular, it is important to emulate the observed in situ ground support performance, as well as the influence of the installation sequence of the support. However, the time and expertise required for this type of modelling of ground support is often not available at mine sites. Even when the expertise is available, it requires a major time commitment and commitment of resources to set up, run and calibrate the sophisticated models capable of explicitly capturing the behavior of ground support.Rock reinforcement is an integral part of all ground support systems used in underground mines. Long, flexible tendons can reinforce the rock mass deeper into the walls and create a thicker reinforced shell around the underground excavation. This article focuses on the optimization of the cable-bolting strategy in squeezing conditions at the LaRonde Mine in Quebec, Canada by integrating the 3D distinct element method (DEM) in the design process. A calibrated numerical model is used to investigate a series of cable bolt configurations and provide recommendations for the ground support design."

Jan 4, 2018

By John B. Gustavson

Gold was first discovered in Alabama in 1830. Before a decade had passed more than 20,000 people were employed in the various gold districts scattered across east-central Alabama. By 1849 most of the presently defined gold districts were known with such towns as Arbacoochee, Chulafinnee, Goldville, Pinetucky, and Idaho being the principal mining camps. The California gold rush of 1849 signaled the end of intensive prospecting in the Alabama Piedmont for the precious metal. Reactivation of many of the old gold districts has been attempted several times since 1849. Significant activity and development took place between 1874 and 1880, 1888 and 1916, and 1929 and 1936. Locally, some of the development met with moderate succes. The last productive gold mine in Alabama ceased production in 1935. The sharp increase in gold prices since 1973 has caused renewed interest in the potential values of gold of the Alabama gold districts. Most of the gold workings have been abandoned for nearly 75 years and are for the most part inaccessible for convential property evaluation. The early gold miners and prospectors in Alabama were more intent upon finding and mining the valuable metal than in recording their activities for future generations. No matter how interesting or historically significant these records might have been the miners kept no records and left behind them few maps as clues to their activities. Inasmuch as most of the old gold districts have been extensively mined and prospected during the past 150 years, there is very little chance of finding large deposits through conventional outcrop prospecting methods. Similarly, the present geologic knowledge of the various districts is insufficient to launch successful exploration programs looking for large blind lode deposits in new locations within the general gold bearing region.

Jan 1, 1975

By R. S. Kinasevich

As part of other work related to the studies of kinetic factors that influence the flotation of specific sulphide minerals, specially designed kinetic flotation experiments at Cominco included work done on -65 + 100 mesh and -100 + 150 mesh, high purity galena. The flotation collector used was sodium isopropyl xanthate containing radioactive sulphur-35. Radiation monitoring of the galena fractions from stage flotation tests indicated that the adsorbed radioactive xanthate was uniformly distributed among the floated fractions and the non-floated, or residual portion of the galena. This anomalous behaviour could not be correlated to changes in Seebeck coefficients, to lattice distortions, or to the nature of the mineral surface as revealed by infrared spectroscopy and by microscopic measurements.

Jan 1, 1970

By SHANTAE LEE, ELAHEH TALEBI, Frank A. Drews, ROGERS W. PRATT

Fatigue is a relatively well-investigated topic in the surface transportation industry with a research focus on sleep deprivation and disruption. This paper examines fatigue in mining operations. While mine operators are using or currently introducing technology to monitor fatigue, there is little work that focuses on the operators’ experience of fatigue and the acceptance of fatigue-monitoring technology. Focus groups were conducted to investigate these topics. The results of this research suggest that current fatigue-monitoring systems lack validity, reliability and user acceptance. Overall, these results emphasize the importance of a socio-technical systems perspective to guide interventions aiming at improving miner health and safety.

By J. J. Casey

This paper is one of a series of presentations organized by the Conference of American Society of Civil Engineers with the goal of making significant progress toward an equitable and effective allocation of risks in construction undertakings among the principal parties - owner, contractor and designer. The role I have been assigned is principally one of identification of risk while others will devote greater attention to the allocation of these risks and the contractual arrangements necessary to properly make these allocations. Construction projects are joint undertakings by parties who bring different skills and interests toward a common effort, much as this conference does. A project is not an adversary proceeding and does not benefit from establishment of an adversary mode, as our lawyer friends seek in the resolution of legal issues. Accordingly, I urge upon this Conference the adoption of two basic precepts and guidelines as the criteria for sharing of the risks inherent in construction undertakings toward achievement through mutual effort the common goal of a successful project completed in the shortest time and at the least overall cost. These precepts are: (1) that all risks are rightfully the owners unless transferred to or assumed by another party for a fair compensation; and (2) that the principle guideline in determining whether a risk should be so transferred should be whether the receiving party has both the competence to fairly assess the risk and the expertise necessary to control or minimize it. The sponsors of the conference have provided certain guidelines to the authors. There is, however, no constraint in expressing one's bias and I suspect that my contractor's outlook may be inherent in my comments. The guidelines have suggested that I indicate whether the risks identified are ones that can or should be shared or borne by one party alone. In doing so, I will attempt to follow the precepts I have recommended.

Jan 1, 1979

By H. Colijn

Vibratory or oscillatory conveyors can be found in all types of industry, handling virtually any granular bulk material, often at elevated temperatures. These conveyors can be combined with other process functions, such as screening, cooling, drying and dewatering, while conveying. Although construction and installation is relatively simple, the engineering and design analysis of the vibratory mechanics is fairly complex. This paper will discuss the basic types of vibratory conveyors and the analysis of the material movement along the carrying trough.

Jan 1, 1985

By M. SIDDARAJU, Rameshwar Sah, T. Umadevi, K. S. SRIDHARA, M. RAJU, GANESH SHETTY

With the depletion of high-grade iron ore resources, the utilization of existing low-grade iron ores, fines and tailings with effective beneficiation is inevitable to meet the iron and steel industry’s required specifications and demand. JSW Steel Limited is operating a 17-mtpa beneficiation plant at its Vijayanagar site in Bellary in Karnataka, which produces nearly 50 to 54 percent concentrate as sinter-grade fines. The sinter base mix consists of iron ore fines that are smaller than 10 mm, with 41 percent smaller than 0.150 mm; washed ore that is generally smaller than 3 mm and bigger than 0.150 mm, with 3 to 9 percent smaller than 0.150 mm; beneficiation plant concentrate, with 97 percent smaller than 0.150 mm; limestone; dolomite; coke breeze; lime; sinter return fines; direct reduced iron (DRI) fines; and micropellets produced from steel plant waste. Using more washed ore in the sinter base mix affects the sinter quality. Ball formation in the mixing and nodulizing drum is an important step in sinter making and requires sufficient quantity of smaller than 0.150 mm fines. Optimization of fines in the sinter base was carried out by replacing the smaller than 10 mm iron ore fines with washed ore. Size analysis, study of the granulation index (G index) and optimization of moisture with respect to sinter bed permeability were carried out to optimize the proportion of smaller than 0.150 mm fines in the sinter base mix as adhering material. This study explores the optimization of fines in the sinter base mix for ball formation to achieve higher sinter quality and productivity with higher sinter bed permeability.

By MATTHEW HART, THOMAS BAMFORD, Kamran Esmaeili, MICHAL KOWALCZYK, FILIP MEDINAC

Improved haul road conditions can positively impact mine operations resulting in increased safety, productivity gains, increased tire life, and lower maintenance costs. For these reasons, a monitoring program is required to ensure the operational efficiency of the haul roads. Currently, at Bald Mountain mine, monthly site severity studies, ad hoc inspections by frontline supervisors, or operator feedback reporting is used to assess road conditions. These methods are subjective and provide low temporal resolution data. This case study presents novel unmanned aerial vehicle (UAV) technologies, applied on a critical section of haul road at Bald Mountain, to showcase the potential for monitoring haul roads. The results show that orthophotos and digital elevation models can be used to assess the road smoothness condition and to check the road design compliance. Moreover, the aerial mapping allows detection of surface water, rock spillage, and potholes on the road that can be quickly repaired/removed by the dedicated road maintenance team.

Sep 15, 2020

By E. H. Cho

An acid mine drainage sludge sample containing 3.6% Mn, 0.18% Ni, 0.15% Co and 0.39% Zn was obtained from the central part of West Virginia and leached with sulfuric acid at pH 3 and at room temperature. Air was bubbled through the leach solution to precipitate the iron content from the solution at pH 4.5. The leach solution contained 258ppm Zn, 105ppm Ni, 90ppm Co and 2050ppm Mn. Three distinctive solvent extraction studies were performed to selectively extract these metal ions in a sequential operation with DEHPA, Cyanex 272, and then Lix 84. The AIO ratio was 1 and the extractants were diluted 10 times with kerosene. A study of solvent extraction with DEHPA showed that Zn could be extracted without Ni or Co up to pH 2.75. A pH of 2.75 is considered to be the optimum pH to maximize the selective separation of Zn from Mn. The separation factor of Co over manganese suggests that the two metal ions be extracted together by Cyanex 272. The separation factor of Co over Ni indicates that these two metal ions can be separated most effectively around pH 5.3. Also, Ni can be effectively extracted by Lix 84 above pH 5.5.

Jan 1, 1993

By Frank Ruskey

Many problem associated with potential hazards in a proposed mining area may not be adequately appraised because of the complexity of trying to evaluate them in terms of production requirements. Frequently, encountered hazards have to be dealt with by day-to-day operational schemes that require the miner to either force a way through them or avoid them by blocking off the area in which the hazards are known to exist. These considerations, after the mine is in full production, can be costly to the mine operator and can increase the danger to the miners. A hazard-evasion computer program for mine planning that will appraise proposed mine layouts on the basis of existing or potential hazards has therefore been developed. The program is intended for use during the planning phase of a mine, where it should assist the mining engineer in making decisions in mine design. With the output from this program, the mining engineer should be able either to corroborate his judgments made on the basis of mining experience or to find unanticipated solutions to design problem. The program tests hundreds of possible solutions to a mining layout, and by sorting out the 10 best (based on a criteria of minimum-abandoned-coal) limits the number of choices that need to be considered and appraised for applicability to a given mine scheme.

Jan 1, 1973

By A. Leppala

Scope of the Courier 300 System The fact that reliable on-stream analysis is a prerequisite for effective flotation control is hardly disputed today. Nevertheless, up to now no system has been available that includes all the equipment necessary for successful analysis. However essential an on-stream analyser is in itself, reliable and accurate assaying can only be assured after techniques for sampling, handling the slurries and computing the X-ray data have been developed for the purpose. The Outokumpu Company's Courier 300 System is a complete package that can be installed and handed over with the key. It includes the equipment needed for sampling and handling the slurries. It has been developed from the start to meet industrial demands. Obviously an on-line system must comply with far stricter standards than one designed for a laboratory. Assays are computed by an Outokumpu 316 digital data processor, which is an integral part of the system and controls its entire performance. The computer software is programmed as a standard package, including a highly advanced new model for assay computation. Analysis output is available for a process computer, report typewriter:, and recorders. The package also includes calibration for slurry assays at our pilot installation before delivery. A complete Courier System can analyse up to 4Z slurries and six elements in each slurry. Thanks to its modular design, it can be dimensioned initially to the customer's requirements and is easy to expand later at low cost. Being a mining company itself, Outokumpu has been able to utilize its own long experience in non-ferrous metallurgy - an important factor contributing to the success of the Courier system. History of the project and present installations The first on-stream analyser was installed at Outokumpu'a Pyhasalmi Con¬centrator at the end of 1967, after several years' development. Since then,

Jan 1, 1971

By W. Hermülheim, J. Brune

"This paper analyzes mine emergency management and rescue practices in German underground coal mines and compares them to those used in the United States. The German mining industry has developed these practices over more than 100 years, and they have successfully managed numerous fire, water inundation and ground control emergencies using these techniques. The authors interviewed German mine emergency professionals about rescue team and emergency operations. These operations were then analyzed to determine which of these German principles would be of interest to United States mine rescue teams. Implementing these programs into United States mine rescue and emergency operations was analyzed. INTRODUCTION Coal mining has become much safer industry than it has been in the past. Advances in safety and health regulations and company polices have improved working conditions for miners all over the world. Even with these advances there is still a need for continued attention to safety and health. It is also important for mine safety professionals to observe practices and procedures in other countries and cultures and learn what and how to apply this knowledge in their own systems. Coal mine rescue has been an integral part in improving coal mine safety. Mine rescue procedures have evolved with time, experience and technology development. Today, coal mine rescue teams are still needed and must be continually trained and prepared for any mine emergency. Although it is hoped that improved mine safety policies and practices will eliminate coal mine disasters in the future, accidents remind us that disasters can still happen today. In May 2014, Turkey experienced a severe coal mine disaster where 301 people were killed [G.Tuysuz, 2014]. Our industry must learn from these incidents, focusing on disaster prevention and making improvements in mine rescue operations. Mine rescue procedures differ from country to country due different regulatory environments and different historical evolution of emergency response. Sharing practices and procedures from one country to another enables learning from different experiences and cultural backgrounds. Sharing is also a way of preserving information, identifying and learning best practices."

Jan 1, 2015

By Gordon Clark, Basar Arioglu, Nasri Munfah, Sanja Zlatanic, Tolga Togan

"The 13.2 m (43 ft) external diameter, double deck Istanbul Strait Road Tube Crossing is one of the most challenging underwater tunnel projects in the world. Subjected to 11 bars of hydrostatic pressure, variable geology, and being in a very active seismic area, the execution of the project required innovative solutions, sophisticated construction techniques and prudent risk management approach. The 5 km (3.1 mile) tunnel consists of a 3.4-km (2.2-mile) tunnel boring machine- (TBM) bored tunnel, 1 km (0.62 mile) twin NATM tunnels and cut-and-cover sections. The project is being delivered in a build-operate-transfer (BOT) contract in a public-private partnership. The technical challenges, coupled with financial and commercial risks required the implementation of sophisticated risk management tactics including the provision of independent design verification. The project was opened to traffic on December 20, 2016, four months ahead of schedule.. This article presents the technical challenges of the project from the design, construction, and risk management aspects..Project backgroundThe $1.245 billion Istanbul Strait Road Tunnel Crossing project, dubbed the Eurasia Tunnel, is one of several major infrastructure projects being implemented in the Republic of Turkey in a public-private partnership approach. The project provides a direct and easy connection between the Anatolian (Asian) side of Istanbul and the heart of its historical district on the European side across the Bosphorus Strait which connects the Black Sea with the Sea of Marmara. The project improves connections to a wide network of motorways on both sides, increase capacity across the Bosphorus by 100,000 vehicles a day, reduces congestion and saves motorists an average of 45 minutes of commuting time in each direction bringing significant economic benefits to the city and the region. It eases traffic across the strait, reduces congestion, decreases pollutants and emission while maintaining Bosphorus. It is the most complex part of the project with the greatest challenges and risks. Part 2 is 5.4 km (3.6 miles) long consisting of 3.4 km (2.2 miles) of 13.2 m ( 43.3 ft) external diameter TBM bored tunnel under the Bosphorus Strait, 1-km (0.62-miles) of twin NATM tunnels on the Asian side, cut-and-cover transition boxes in the Asian and the European sides and depressed approaches on both sides. In addition, this segment includes the toll plazas, ventilation buildings, and the tunnel control and maintenance facilities."

Mar 1, 2017

By G. van Eck, H. Smit, L. Meyer

The Cook Islands (CI) possesses within its Exclusive Economic Zone (EEZ) a massive field of polymetallic nodules representing one of the world’s largest undeveloped cobalt deposits, along with large quantities of other metals critical to achieving global energy transition targets. In February of 2022 the Seabed Minerals Authority (SBMA) of the CI granted Moana Minerals a license to conduct our nodule exploration program. This paper describes how Moana Minerals chose to approach conducting exploration activities, one of the greatest challenges to Deep Sea Mining (DSM) development and the securing of the social license to advance to eventual mining of the resources, in an unconventional manner. The remote location of the project poses logistical challenges in mobilizing to and operating in the region and is a significant cost driver. Historically, exploration campaigns mobilized large vessels from mainland Europe, the Americas, and Asia as this model works well when contemplating long duration and widely temporally spaced campaigns without the need to revisit. Moana Minerals, when considering these challenges determined a multi-year deep sea mining (DSM) exploration program conducted in such a remote location can be better optimized by the deployment of a smaller yet highly capable “exploration optimized” vessel that is dedicated to the task and is based full time in the Cook Islands. INTRODUCTION The paper describes the challenges of exploration in remote regions including the South Pacific, and how an unconventional consideration of the problem led to the solution. Completion of an Environmental and Social Impact Assessment begins with a detailed environmental scoping study, resource update sampling requirements, and engineering data and sample requirements, which identifies the exploration goals of the project and technology needed to accomplish those goals. The method walks the reader through vessel and technology selection, discusses the challenges of equipment selection considering size and capability, describes the final arrangement, and provides results from the initial exploration campaigns. We followed the project from conception through the shipyard conversion, mobilization, and initial operations in the Cook Islands. The result shows how a smaller vessel with limited budget makes a large impact on the exploration capabilities in the region while building public trust. The Anuanua Moana is the first dedicated deep sea minerals exploration vessel modified with a suite of technologies that allow it to compete technically with existing ships but operate locally in the smaller ports of the South Pacific. The unique combination of size and technical capability gives the Anuanua Moana advantages over other vessels. This paper shows the importance of the Anuanua Moana in the development of offshore exploration strategies in the emerging deep sea minerals space.

Feb 22, 2026

By Peter M. Fozzard

A review is made of the actual costs of recent foreign mineral exploration programmes in third world countries. Target identification leading to the selection of areas, or macro-targets, must follow a well planned and defined series of steps. Suggestions are made with respect to this inter-active project development work. Potential revenues in the broad sense will always determine the overall economics of exploration but clear objective philosophy, good planning and adequate financing are essential for exploration success. Considerable opportunities exist for making important foreign mineral discoveries and broad selected suggestions are made for the identification of exploration areas in relation to high-grade and precious metal mineralization.

Jan 1, 1984