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By O. Porterfield, M. O’Kane, M. Endersby

BHP Iron Ore initiated research programs in January 1995 to develop long-term plans for decommissioning waste rock material at its Mt. Whaleback operation. More than 2 Gt (2.2 billion st) of waste rock were deposited during the past 30 years. Ultimately, a total of 4 Gt (4.4 billion st) will be deposited in waste rock dumps constructed near the open pit. The Mt. Whaleback operation is located in a semiarid climate adjacent to Newman, Western Australia. The primary research program includes the development of technology for the long-term performance of the waste rock dumps with respect to vegetation, slope stability, surface runoff, erosion and water infiltration. This paper focuses on the design and implementation of a cover system to prevent water infiltration to the underlying waste rock. Data obtained from a laboratory program and from soil-atmosphere modeling was used to design horizontal field test plots. The construction of the horizontal surface field test plots is discussed together with the field instruments installed to monitor performance. The cover system is designed to maximize infiltration during wet periods for subsequent evapotranspiration while minimizing surface runoff. The result is a near-zero net infiltration to the underlying waste material. An important feature of the design is the use of run-of-mine waste material as the cover material. Monitoring is in progress and will continue for at least two annual wet/dry cycles. The optimum cover system should minimize the net infiltration of water to the underlying waste rock while maintaining physical and ecological integrity for long-term performance.

Jan 1, 2000

By P A. Lang, J G. Ayotte, R W. Humphries

Atomic Energy of Canada Limited (AECL) has the responsibility for research, and development of technologies, for the safe and permanent disposal of Canada's nuclear fuel wastes. As part of this comprehensive program, AECL is constructing an Underground Research Laboratory (URL) near Lac du Bonnet, Manitoba, to evaluate aspects of the concept of waste disposal deep in stable geological formations. No nuclear wastes will be used in the URL program.

Jan 1, 1986

By Harald Vogel, Johannes Lachenski, Friedemann Koetzel, Sebastian Schnell

In this paper, a digital subsoil approach, a work-in-progress, will be presented describing the transformation from a classical 2D to digital 3D thinking process in the design of geotechnical structures. Certain pitfalls as well as lessons learned are described, and the reader can understand that the digitalization process of the design of geotechnical structures is always a problem-focused approach by creating systems for certain processes rather than setting rules or regulations. Three project examples are presented. Two of the presented project examples feature a heterogeneous geology distribution and made it necessary for the design of the foundations to work with 3D subsoil and 3D calculation models. However, the digital 3D design process in the third project, an inner-city excavation pit, is driven by the complicated boundary conditions making it necessary to work in a parametric 3D design space. All projects have in common, that new processes had to be developed. The paper concludes with a flow chart describing the process of the elaborated digital subsoil approach.

May 1, 2022

By B Taylor, S Evans

Bulk explosive technology for underground mining has not seen any significant technological advances since the widespread transition from ammonium nitrate fuel oil (ANFO) to ammonium nitrate emulsions (ANE) commencing in the 1980s. The in-hole energy profile that conventional ANE systems deliver is limited by the physics of chemical gassing and simple control systems. This compromises the range, precision, and accuracy of energy delivery into the blasthole, and in some cases limits the length of charge that can be delivered. Orica’s 4D™ bulk system removes many of these constraints, enabling better blasting performance across all underground mining methods. This paper reviews work completed at three mining operations across Australia, the United States, and Chile with a focus on how this system can improve mining operations and deliver sustained commercial and productivity benefits into the future. These benefits include improved ore recovery, reduced dilution from waste rock, and reduced overall explosives consumption. This paper also reviews how this new technology can be applied for planning future mining operations.

Sep 1, 2024

By S Warden, T Neville, P Leckie

At its simplest, the classification and characterisation of an orebody is a matter of Where, What and When. Where and with what spatial resolution are measurements taken, What properties are measured, and When are the data acquired, processed, and delivered to create the most value. This paper delves into how existing and near-term advances in measurement technologies, field automation, and whole-system-digitisation are combining to open new routes for mine and exploration productivity improvement. Commencing when the initial exploration hole is dug, the advancement in deployment of survey technology—from expert-operated, to driller-operated, to driller-integrated—is used to demonstrate a template for adoption of higher technology measurements. We then introduce and discuss the multi-use measurement as offering outsized returns from a single measurement run, highlighting two new technologies that acquire rock strength while drilling and downhole assay data as examples. For rock strength, we highlight a novel approach to determining Uniaxial Compressive Strength (UCS) while drilling, its relationship to and advantages over Mechanical Specific Energy (MSE), and how it offers utility to multiple downstream processes. For downhole assay, we detail how a back-tophysics approach to Pulsed Fast and Thermal Neutron Activation (PFTNA) analysis offers significant advantages over other measurement methods and earlier implementations of PFTNA, generating a rich data set that can significantly extend and improve the information on which mining decisions are made. Finally, we discuss the possibilities enabled via optimising data delivery, collection, and curation— noting a fundamental limitation of historical systems and exploring the possibilities that will be unlocked by soon-to-market solutions that better enable Orebody Characterisation data to (virtually) move in space and time with rock material post-blasting. Ultimately, the value of optimising the Where, What, and When from point of measurement to the moment it generates maximum value will create greater life-of-asset production for a lower cost and energy input.

Sep 1, 2024

By C Jacobsen, N Harries

Assessing and managing instability hazards is an essential activity when working with unstable natural slopes and excavated open pit mining slopes. Slope monitoring has become the standard technique for the management of geotechnical risks associated with mine slope instability hazards. In recent decades, a proliferation of new monitoring techniques such as terrestrial radar, satellite InSAR and LIDAR have become standard operational tools, complementing conventional survey-based monitoring solutions. A reliable monitoring system should identify and record incipient anomalous slope movement. Although the most obvious purpose of a monitoring system is safety related, slope deformation and performance monitoring also enhance the understanding of slope behaviour and assists in improving system design and implementation. For a monitoring system to be considered an effective early warning tool, it needs to operate in real-time and should be linked to the mine’s emergency communication systems. Terrestrial radar systems have been developed that can provide near real-time measurements, at a high level of precision and covering broad areas in all weather conditions. This has had a positive impact on the management of geotechnical risks in operational conditions. The technology adoption of RADAR in mine monitoring has significantly progressed in the last 20 years from technology enthusiasts, to visionaries, to pragmatists to conservative users. However, the increasing adoption of RADAR cannot reduce or remove other monitoring techniques that often have important benefits; even if these technologies cannot be used as a real-time operational tool. An increasing awareness on the importance of combining data from different monitoring techniques to develop a holistic picture of all possible geotechnical hazards is a current industry trend. This is proving to be an excellent foundation for managing hazards associated with slope instability in open pit mines, and is only expected to improve with time with the adoption of new technologies based on big data and Artificial Intelligence (AI).

Nov 29, 2022

By Peter Faust

"The south access road to San Francisco’s Golden Gate Bridge, known as Doyle Drive or Presidio Parkway, needs to be replaced. Built in 1936, it is the primary highway and transit linkage through San Francisco between counties to the north and south. The roadway is tucked into the natural contours of the Presidio and the Golden Gate National Recreation Area, one of the nation’s largest urban parks.The old steel truss structure will be replaced by a new concrete cast-in-place bridge. The foundation design of the new bridge is based on drilled mono shafts below each bridge column. Most shafts required large diameter permanent steel casing installed under strict vibration limitations since several historic landmarks are near the project alignment. Malcolm Drilling decided to use the largest oscillator in the world to install the piles.The area occupied by the Presidio is generally hilly, sloping down northwards to San Francisco Bay. In the western half of the project route, two bluffs rise steeply to about 80 ft (25 m). The bluffs are separated by a valley 60 ft (18 m) deep and 1,500 ft (457 m) wide, which is spanned by the old and new bridge. Overburden soils in this valley are made up of artificial fill, slope debris, ravine fill and Colma Formation, a fine to medium-grained sand unit with clay beds. The Bay Muds encountered in the project area are typically soft clayey silts, becoming medium stiff with depth.The basement rocks underlying the overburden belong to the Franciscan Formation, described as shale, sandstone, serpentine and greywacke, it is extremely variable in hardness, fracturing and weathering. The material can vary from very hard to very soft, can be slightly to very intensely fractured and almost not weathered, to totally decomposed within relatively short distances both laterally and vertically. Rock strength can vary from too weak to be tested to serpentine layers with unconfined compressive strength of 15,000 psi (103MPa) or higher. Groundwater levels in the area are typically no more than 10 to 20 ft (3 to 6 m) below the ground surface."

Jan 1, 2012

By Olgun

Energy piles are a new innovative renewable energy technology to access and exploit the relative constant temperature of the ground for efficient heating and cooling of buildings. Examples of energy piles include drilled shafts, continuous flight auger (CFA) piles, driven piles, and micropiles. A field test setup was installed at the Virginia Tech Geotechnical Research Facility to study energy piles. The field test consists of a total of five micropiles 25 cm (10 inches) in diameter, four of which were equipped with circulation loops. The test piles extend to a depth of 30.5 meters (100 feet) and are heavily instrumented with strain gauges and temperature sensors. Several observation boreholes were formed around the test piles to monitor ground temperatures. Thermal conductivity tests and field load testing were performed to investigate the behavior of Energy Piles. This paper presents results of the thermal conductivity tests and thermo-mechanical field load test performed as part of this field investigation.

By Gilbert Chuah, Peter Middendorp, Joost Bakker, Soon-Hoe Chew

"The Rapid Load Testing (RLT) of foundation piles has been applied worldwide since 1984. Several International and national codes are available, such as the Japanese Code of Practice (2002), ASTM D7383-2010, German recommendation on Piling (2012) and Eurocode (2015). RLT methods like Statnamic and StatRapid are gaining popularity in Asia, Europe and North America. For checking the performance of piles, they are more economical, faster and environmentally friendly than Static Load Testing (SLT), while yielding good correlations with SLT results through an objective analysis method. To date (October 2016) hundreds of piles have been successfully tested by RLT method in Singapore. A number of these RLT tests were coupled with static load testing correlation tests, some of them with instrumentation for shaft load transferred. Examples of some correlation results for foundations installed in various geological formations in Singapore are presented in the paper. The findings from these results indicate that loading rate effects are negligible for Rapid Load Test results when foundations are socketed in competent non-cohesive soil layers and derive most of their capacity from these soil layers.INTRODUCTIONRapid Load Testing (RLT), by which a quasi-static load is applied to a foundation pile, is used increasingly as an alternative to Static Load Testing (SLT) for cast in-situ piles, such as drilled shafts or bored piles. It is recognized nowadays that the determination of the pile capacity with Dynamic Load Testing (DLT) through signal matching techniques such as CAPWAP, TNOWAVE and AllWave-DLT, yield a wide spread of results for cast in-situ piles (Stahlmann et. al, 2012), making it practically very difficult, if not impossible to calibrate the DLT results with SLT results. This spread is due to the empirical and subjective assumptions that are used to interpret the test data, especially for cast insitu piles (Holeyman et al. 2001, Viana da Fonseca in 2008, Herten et al, 2013). This is further complicated by the inhomogeneity of the concrete and variable cross-sections over the pile length for the cast in-situ piles."

Jan 1, 1900

By Paolo Cavalcoli, Federico Pagliacci

"As opposed to the static functional recovery of existing structures, the construction of infrastructures in an urban environment, when combined with complex geological situations, often involves building foundation structures, whether circular or rectangular in section, through rock formations or chaotic strata (sand and gravel with cobbles). Until a few years ago, these formations or strata were sometimes an insurmountable constraint on traditional foundation installation techniques. The difficulty in overcoming these geological situations is sometimes added to the increasingly frequent need to reach depths that were unimaginable just a decade ago. These are real challenges for those carrying out these works and for those manufacturing the necessary equipment. There are two main methodological approaches to these problems, that can be summed up in the rhetorical figure of ""David and Goliath"": cunning versus force. In reference to the case studies in this article: the permanent retaining walls for the Copenhagen Metro, and the structural repairs to the Arapuni Dam in New Zealand and the Wolf Creek Dam in the U.S., we will describe the foundations constructed in presence of rock using combined small-diameter direction drilling solutions, associated with their enlargement up to the project’s size, at depths exceeding 300 feet. Finally, a case study will be presented on the implementation of a large cross-section of an excavation in the rock, at depths greater than 800 feet.IntroductionAs opposed to the functional recovery of existing structures, the construction of infrastructures in an urban environment, when combined with complex geological situations, often involves building foundation structures, whether circular or rectangular in section, through rock formations or chaotic strata (sand and gravel with cobbles).Until a few years ago, these formations or strata were sometimes an insurmountable constraint on traditional foundation installation techniques. The difficulty in overcoming these geological situations is sometimes added to the increasingly frequent need to reach depths that were unimaginable just a decade ago.These are real challenges for those building these works and for those manufacturing the necessary equipment. There are two main methodological approaches to these problems, that can be summed up in the biblical figures of ""David and Goliath"": cunning versus force. In the engineering field, the force is summarized in the use of ever-larger drilling equipment in terms of installed power, weight in working conditions, winch and rotary capacity."

Jan 1, 2015

By Ralf Plinninger, Pafos Busch, Richard Gradnik

This paper presents the details of the Bad Bergzabern tunnel project. This tunnel is the main part of the B427 federal road bypass, intended to improve the regional traffic infrastructure and to reduce the traffic load in the historic city centre of the health resort Bad Bergzabern. Located in the south-western part of Germany, the project area is situated at the eastern margin of the so-called Palatinate Forest, a low mountain region of mainly triassic sediments with a complex and variable geological history. The German federal government, represented by the office of mobility of Rhineland- Palatinate, awarded the contract to BeMo Tunnelling, a specialized Tunnelling company with a long history of innovation and success in NATM tunnelling. The contract includes the construction of two separate tubes with a length of approximately 1,44 km (0.9 mi)—the road (main) tunnel with a cross section of 101 m2 (1,090 sq ft) and a parallel rescue tunnel with a cross section of ca. 23 m2 (250 sq ft.) Both are connected by six cross passages. Tunnels and cross passages are excavated according to the principles of the New Austrian Tunnelling Method (NATM). Due to BeMo Tunnelling’s technical expertise and capabilities, the project team was able to engineer a speed-up concept that saves money and time for the construction team and client. This paper presents the innovative approach BeMo Tunnelling made to optimize the execution of the tunnelling works and the challenges the project team is facing with regard to a complicated geological situation, countermeasures against an increasing effect of climate change and volatile prices for construction materials.

Jun 13, 2023

By Stanko Nikolic, Oscar Mendoza, Christian Pasten, Stuart Nicol, Ben Hogg

ISASMELT™ technology is based on the use of an elegant furnace system design which uses submerged lance technology to provide highly efficient mixing and reaction of feed materials in a molten slag bath. Within Peru the ISASMELT™ technology has been applied to the Southern Copper Ilo Smelter, part of Grupo Mexico. Southern Copper selected the ideal technology to meet their sulphur capture and particulate emissions requirements whilst minimising capital and operating costs. The commissioning of the ISASMELT™ in 2007 marked the modernisation of the primary smelting section of their smelter, with traditional batch converters still used for the secondary smelting stage of the copper production flowsheet.

Sep 30, 2022

By Q Yang

This paper describes the design and construction of three 7.2 m span access ramp-tunnels to the three level underground car park of the newly redeveloped Top Ryde City Shopping Centre in northern Sydney. The tunnels were to be excavated without significant impact on the overlying Devlin Street, one of the busiest arterial roads in the Sydney metropolitan area and a major link in the Sydney road network. The interpretation of the geological conditions indicated that the tunnels would be driven in a formation of heavily jointed, extremely weathered to fresh Triassic Ashfield shale with some structural features such as dyke, fault and shear zones identified in the available boreholes logs. Both empirical and numerical methods were used to design the tunnels and to predict the ground surface settlements. The design solution, which was influenced by the relatively small scale nature of the work and the current demands on the tunnel construction market, included presupport, initial support and permanent steel fibre reinforced shotcrete (SFRS) lining. The interactions of the driven portals with cut and cover sections and the proposed deep excavation of the new shopping centre were considered at the design development stage and in the construction phase to ensure the safety of the live road. The tunnels have been successfully constructed and are now operational.

Mar 8, 2011

By L Keeney

Cu-Au porphyry deposits are large tonnage low-grade resources dependent on processing large volumes of material. The ability to understand and predict comminution performance is critical, as it is frequently the rate-limiting step during processing. Parameters required from geometallurgical mapping and modelling of comminution performance are: A×b processing domains based on impact breakage variability, and BMWi processing domains showing grind response variability which lead to Mine throughput domains for a specific comminution circuit configuration. Due to the cost and/or large sample requirements of traditional comminution tests, insufficient data density and distribution of comminution indices commonly exist, making it difficult to model and map deposit scale variability. One method routinely applied to three dimensional domaining is to have an a priori zoning based on geological features (lithology, alteration, mineralogy, textures), and then apply to all material within a given domain the metallurgical values measured on a single sample or average of samples from that domain. The problem with this approach is that commonly the geological domains do not reflect comminution response, therefore compromising the quality of the average domain estimate. To resolve this problem an alternate integrated geometallurgical mapping and modelling method is applied to model and map comminution performance at Cadia East. This paper uses a data set of ~32 000 assay measurements and geological logging information, integrated with ~150 comminution measurements to analyse and develop proxy support models for comminution indices (ie A×b, BMWi, and throughput) based on inherent geological variability. Discrete downhole comminution processing domains are created, mapping orebody response while maintaining inherent variability.

Sep 5, 2011

By H Jones

The paper outlines the adoption and evolution of ‘sustainable development’ as a concept in tailings management practices in the mining industry over the last 30 years. Over 500 lives have been lost in tailings facility accidents since World War 2. The paper outlines commonalities in many of these accidents, particularly the role of excess water. It considers the role effective tailings management can play in enhancing the social acceptability of mining in the future.Tailings management is a major operating cost at many mines while the cost of successfully closing tailings facilities is also very high. Current tailings management practices in the industry are outlined. The technical and engineering challenges of reducing potential risks associated with tailings by reducing water entrainment are described. The successful development of practical techniques to better manage tailings and reduce water consumption and wastage are described. For example, water removal in the alumina industry to produce a paste for dry stacking is now a reality.The future adoption of these new risk reducing techniques by the industry is discussed and the implications of the adoption or non-adoption of these techniques on the industry’s future ‘social licence’ is considered.

Nov 22, 2011

By Germán Toledo

The closure of TSF represents a critical milestone in the life cycle of mining operations, requiring the integration of technical, environmental, and social dimensions to ensure long-term safety and sustainability. The GISTM introduces the concept of “safe closure” as a demonstrable technical condition in which there are no ongoing material risks to people or the environment. This status must be validated by an independent technical reviewer and formally approved by the Accountable Executive. This article presents a risk-based methodology to support the achievement of safe closure, aligned with the principles and requirements of the GISTM. The proposed approach emphasizes the need to identify, assess, and manage closure and post-closure risks progressively throughout all phases of the TSF life cycle: from site selection and design, through construction and operation, to closure implementation and long-term monitoring. The methodology integrates key elements of effective risk management, including comprehensive knowledge bases, consideration of climate change, credible failure modes, continuous monitoring, stakeholder engagement, and governance. The ALARP principle is applied to demonstrate that residual risks have been reduced to tolerable levels. By incorporating closure planning from the earliest stages and adopting a risk-based view throughout the entire life cycle, this methodology aims to support mining organizations in achieving a verifiable and responsible closure of tailings facilities, in line with international best practices such as those of ANCOLD and ICOLD. The proposed framework offers a practical contribution to strengthening the credibility, effectiveness, and sustainability of tailings closure processes.

Feb 22, 2026

By Engineering Staff

"This paper briefly describes the surface mining operations at Smoky River Coal Limited (formerly McIntyre Mines Limited, Coal Division) near Grande Cache, Alberta. Geology, mining methods, equipment, manpower and reclamation and environment topics are discussed. Introduction Smoky River Coal Limited, a wholly-owned subsidiary of McIntyre Mines Limited of Calgary, Alberta, produces a high quality, low sulphur, low volatile bituminous coking coal from its minesite located at west central Alberta, approximately 20 km from the town of Grande Cache and 360 km west of Edmonton (Fig. I). Most of the coal property is contained within a 30 km long by 20 km wide block lying in a northwest-southeast direction in mountainous terrain. Elevations vary from 920 m above sea level ·at the plant·site on the Smoky River to 1,600 mat the upper levels of current and proposed mining operations. A total of 11 coal seams have been identified. Only two seams, No. 4 Seam and No. 10 Seam are currently considered of major commercial value. These seams are recovered by both surface and underground mining. Approximately 650Jo of the plant feed coal is obtained from a conventional shovel/truck surface mine; the balance is mined underground by room-andpillar methods. Background In 1921, McIntyre Mines Limited acquired some 26,300 hectares of coal leases at Smoky River. Since then the leases were explored intermittently by different companies including McIntyre. In the mid-l 960s exploration activities increased and several feasibility studies were completed. Development of the area was undertaken by McIntyre in 1968 and, in August of the same year, a long-term contract was signed with a consortium of Japanese steel mills for delivery of 2 x 106 t of clean coking coal for 15 years commencing in 1970. Production was focussed on underground mining, using longwall methods."

Jan 1, 1985

By D. A. Buckingham

The Bureau of Mines evaluated potential availability of domestic nickel from 23 deposits, Evaluations included an estimation of in situ and recoverable resources, applicable mining and processing technologies, and capital and operating costs. Discounted cash flow analysis with a 15-pct rate of return was used to determine the average total cost of production of each operation, Identified in situ resources contain 9.0 million metric tons (t) of nickel; 5.5 million t is recoverable as nickel metal or ferronickel. Demonstrated in situ resources contain 8.2 million t of nickel; 4.8 million t is recoverable as nickel metal or ferronickel. No nickel is available at a total cost of production equal to the January 1983 market price of $3.24 per pound. Analyses indicate that potential annual production can only meet current consumption levels at a total cost of production of $7.60 per pound of nickel, Nickel's availability is contingent on (1) successful adaptability of nickel processing methods to domestic resources, (2) location of a smelting facility, and (3) marketability of byproducts and coproducts. Analyses were performed on the effects of byproduct and coproduct revenues, energy, labor, and transportation costs, and metallurgical recoveries on nickel's availability.

Jan 1, 1984

By R. Lusignea

This report describes the development of a device for the nondestructive testing of resin grouted roof bolts by means of mechanical frequency response. Various alternative methods were evaluated and the mechanical frequency response method was selected. An interactive program of design, testing, and development culminating in the current prototype instrument demonstrated the capabilities of the method and suggested potential applications of the instrument. The resin bolt testing device utilizes a swept frequency dynamic compliance measurement in the 1 to 2 kHz range which is interpreted by an electronic signal processor to give a "GO" or "NO GO? readout. Field tests have shown that the device can reliably determine the bond quality of the front half of the bolt (nearest the roof surface). Tests were carried out on both experimentally installed bolts and typical mine bolts installed by a conventional bolting machine. The development program has led to recommendations for improvement of the prototype and future development work.

Jan 1, 1979

By G. T. Austin

This is an overview of the gemstone industry with special attention on particular states within the united states. The U.S. Bureau of Mines, Department of the Interior compiled and analyzed the information contained in this report. The report should be viewed as a current "still photograph" of a dynamic system. The information presented on a specific gemstone or for a specific state can and will change with time. This overview presents historical and reference information on the principal gemstones and their production in certain states. The report is not a definitive work on gemstones within the select states or United states.

Jan 1, 1995