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By John Kuyt, Zili Li, Michael Mooney, Michele Mangione

"INTRODUCTIONTwin bored tunnels are commonly used for a variety of road and tunnel projects throughout the world. A major component of these twin tunnel projects is the construction of connecting cross passages that provide emergency access between tunnels and space for tunnel service equipment. Cross passages can present significant geotechnical risk and technical challenges to a project – support systems must be considered for redistributing loads around the mainline tunnel openings and supporting new loading resulting from excavation activities. Additionally, cross passages pose risks to construction schedule and cost because of their sequencing at the end of construction, so mitigation of schedule overruns can be critical. By observing field instrumentation data records from completed projects, a betterunderstanding of the force development in each temporary structure can be achieved with indication of which structures are the most critical to support ground loads.This paper discusses the data obtained during the Brisbane Airport Link construction project, a road tunnel located in Brisbane, Australia. Strain gauge instrumentation data from the precast segmental lining and propped opening steel sets is presented with relation to the construction sequence and local geology. Interpretations and conclusions based on the observed trends are proposed, with several key mechanisms affecting the loading and unloading identified.Brisbane Airport Link Project OverviewThe Brisbane Airport Link project in Brisbane, Australia, connects central Brisbane to the airport located northeast of the downtown with over 7km of twin-bore road tunnels, two lanes each, with several caverns, interchanges, and access ramps constructed along the alignment to connect to other key routes in the city. The project was executed under a Public-Private Partnership (P3) scheme, funded and operated by the consortium BrisConnections. The main contractors were a joint venture of John Holland and Theiss, while the design was carried out by Arup and Parsons Brinckerhoff.Construction of the tunnels was conducted using a combination of 17 roadheaders and two 12.5m double-shield Herrenknecht TBMs [1]. The TBMs were used in EPB-type closed mode for the initial portion of their drive, starting at the northeast end of the alignment. Tunneling started in soft ground, weathered rock, and mixed face conditions initially, progressing to competent sedimentary rocks as the drive continued. Support was accomplished using a 12.1 m diameter steel fiber reinforced concrete (SFRC) segmental lining installed behind the TBMs in a 9 segments + 1 key arrangement. The innovative design of these segments is detailed in the paper by Harding and Francis [2]. Ancillary roads and underground interchange caverns were constructed by sequential excavation techniques using roadheaders, accounting for nearly half of the total underground excavations."

Jan 1, 2016

In this paper, we present design and implementation details of a fuzzy-behavior-based controller for an automated excavator. This robotic excavator must be equipped with sensors, actuators and an embedded control system. The excavator controller uses neural-networks to interpret forces and torques gathered from bucket mounted force sensors during the excavation process. Implementation details and experimental results using the fuzzy behavior based excavation controller are given for several excavation tasks. These excavation tasks demonstrate some of the complex skills that are essential for an autonomous mining excavator controller.

Jan 1, 1996

By Tom Ireland, Sumi Eratne

The approach to Risk Management during the procurement of major projects often has a significant outcome on the ultimate successful delivery of a project. The $NZ4.4B Auckland City Rail Link project is the largest and most complex transportation project yet undertaken in New Zealand. Risk management prior and during procurement was undertaken in accordance the ITIG Code of Practice for Risk Management of Tunnel Works (TCoP) and through the use of an Alliance Geotechnical Baseline report. This paper describes the measures taken during the procurement process to achieve certainty with respect to outcomes and minimise project risks whilst also achieving value for money. This included the use of cloud-based delivery of geotechnical data and 3-D geological models, reducing tendering costs and allowing a focus on risk mitigation measures during the tender rather than data management.

Jun 13, 2021

By W. E. Adkins

Ore and waste haulage usually constitute one of the major cost items in the operation of an open pit mine. This has always been true at the Chino mine, one of Kennecott Copper Corporation's western mines, located in southwestern New Mexico. The Chino Mines Division is an integrated operation. The open pit mine, dump leaching operation, and a precipitating plant are located at Santa Rita, New Mexico, and a power plant, mill, smelter, and fire refinery are located in Hurley, New Mexico, about nine miles south of the mine. Approximately 22,000 tons of ore are mined and processed each day; in addition, approximately 42,000 tons of waste are removed from the pit. Originally the pit was located along the side of Santa Rita Creek but it has deepened and expanded so that at the present time, it could better be described as a nearly circular pit about one to 1.5 miles in diameter. The bottom is at an elevation of 5750 feet, the west rim near the ore gathering yard is at an elevation of 6230 feet, and the highest bench on the east side of the pit is at an elevation of 6750 feet, giving a vertical mining depth of 1000 feet. The train waste dumps reach a maximum elevation of 6580 feet. At the present time, Chino uses electric locomotives, off-the- highway trucks, and a skip system for mine haulage.

Jan 1, 1963

By William Moser, B. P. Shagula

INTRODUCTION Every day mine management and mining personnel face the threat of a possible mine disaster or fire. Their ability to deal with such a situation safely and effectively depends on the level of emergency preparation developed and maintained. After conducting numerous informal evaluations or audits at different mine sites throughout West Virginia (as well as other states), the authors concluded that many mining operations are not prepared to handle a fire situation. The results of the audits indicate that while most mines are in compliance with federal and state legal regulations regarding levels of emergency equipment, water systems and training sessions, these levels - particularly in the area of fire training - are probably not sufficient to enable the mine employees to effectively combat a fire in its early stage. This paper will present the authors' recommendations for designing and maintaining an efficient mine emergency preparedness Program and an overview of the curriculum of the mine fire training Program currently being conducted. MINE EMERGENCY FXEPAREDNESS PROGRAM The Mine Emergency Preparedness Pro- gram (MEPP) is a management tool developed by the Mining Extension Service at West Virginia University and was designed to assist company personnel in effectively managing a mine emergency operation. The program goes beyond the traditional and required training of mine rescue teams by offering a complete emergency operations package. Included in MEPP are suggested approaches for training and organizing all personnel, ideas for developing plans of action concerning transportation, security and communications. The MEPP program may also be used as to assess present readiness levels. While the MEPP program is designed to address all types of emergency operations, the authors are convinced that emergencies involving mine fires are the ones of greatest concern and so are concentrating their efforts in that direction. Incidents where fires are involved seem to be increasing in frequency and are extremely costly to control if allowed to go beyond the incipient stages. With a proper emergency preparedness program in place and properly trained and equipped fire brigades, the authors feel that it is possible

Jan 1, 1992

By M. D. Loy

In addition to products available from private vendors, many useful programs are developed at universities - in fact, many of these programs led the way to commercial development. Other projects are assigned to consultants with backgrounds in system design and mining. Both types of development have led to programs that can be acquired for the cost of a tape or disk. This paper highlights several underground mining packages. These programs consist of: ? USBM model-developed by the United States Bureau of nines. ? PSU model-developed by Pennsylvania State University. ? VPI model-developed by Virginia Polytechnical Institute and State University. ? NUS model-developed by NUS Corp.

Jan 1, 1987

By B. K. Mishra, B. Das, L. Panda, D. S. Rao

"The dissolution behavior of lateritic nickel ore containing 1.2% Ni, 40.6% Fe, 9.5% SiO2 and 9.59% MgO by sulfuric acid was investigated. The ore was characterized adequately by different techniques such as chemical analysis, scanning electron microscope (SEM), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), thermal analysis and Fourier transform infrared (FTIR) spectroscopic measurements. The characterization results did not reveal any distinct mineral phase for nickel; it was associated with mineral phases like goethite, hematite, chromite and serpentine in various proportions. The beneficiation studies by hydrocyclone, magnetic separation and flotation did not enrich the nickel value. Reduction roasting followed by magnetic separation indicated only 2%Ni with 28.9% yield. Consequently, the recovery of nickel values from the lateritic ore by acid leaching under different conditions was studied. The kinetics of leaching obey the first order rate equations. The recovery of nickel was found to be influenced by temperature. It was observed that at an acid concentration of 2M, leaching temperature 363 K, time 240 min and solid-to-liquid ratio of 1:10, it is possible to leach out more than 95% Ni.IntroductionThe demand for nickel is ever increasing. Nickel is used to impart specific properties to steel, titanium and aluminium, and also is used in petrochemicals, catalysts, batteries, etc. It has been estimated that nickel oxide ores account for about 70% of the world nickel reserves. However, most nickel is sourced from sulfide ores. Nickel is extracted from sulfide ore by size reduction, followed by flotation to obtain a nickel-rich concentrate. The concentrate is then pyrometallurgically processed by smelting to produce a nickel-rich matte after discarding an iron-rich slag. Due to the increasing demand for nickel in stainless steel and other alloys, nickel is also extracted from many secondary sources. The recovery of nickel from oxide ores is now gaining momentum, and more exploitation of this ore is being attempted by advanced as well as environmentally feasible, cost-effective techniques. Dalvi et al. (2004) has reported that, due to the increase in demand, the world nickel production from laterites is expected to increase every year from the current level of production. In recent years, investigations of the use of low-grade ores, spent catalysts, clays, etc., have intensified to meet the market demand and also due to a shortage of high-grade nickel bearing ores (Al-Mansi and Abdel, 2002; Baba et al., 2009; Ismail et al., 2011)."

Jan 1, 2015

By Bradley Johnson

Introduction Since its creation in 1910, the Bureau of Mines has conducted a wide-ranging program of research on mining technology. Over the years, the Bureau has perhaps become best known for its accomplishments in mine health and safety technology, a field that has been the object of much public attention. Nevertheless, the Bureau's program in other areas of mining technology has always been strong and remains so today. A distinguishing feature of the current effort is its tendency to concentrate on high-risk, high-gain projects. Throughout the federal research establishment, the Administration's policy has been to phase out short-term research that could be performed by private industry, in favor of long-terms projects that industry cannot usually afford to fund. This tendency is evident in the following account of the highlights of the Bureau's current mining technology research program. Underground Mining Technology Fragmentation. Research studies on fragmentation have focused on nonexplosive concepts. If successfully developed, these concepts would lend themselves to continuous automated operation and reduce time and costs of fragmentation in underground mines. A special laboratory-scale device to investigate ripper cutting was designed and fabricated in 1982. Experiments were conducted with large drag cutters to develop an efficient cutting technique for hard rock. Tests were successfully conducted with 76- and 152-mm (3¬and 6-in.) bits in rocks up to 138-MPa (20,000-psi) compressive strength. Because of the success of these initial tests, larger-scale proof-of-concept tests are planned. To prepare for these tests, a tester capable of cutting a 1.8-m (6-ft) opening was fabricated. This device will allow ripper cutting to be carried out at full scale, and will also allow mucking and holddown requirements to be investigated. Preliminary estimates indicate that this concept has the potential to double excavation rates while reducing costs up to 30%. Mobile Hydraulic Monitor. A mobile hydraulic monitor system was designed, fabricated, and used to mine the St. Peter sandstone at an average rate of 22 t/h (25 stph) from a face in Martin-Marietta's foundry sand mine at Clayton, IA. A slurry transport system worked in tandem with jet cutting, resulting in a continuous mining and transport system. Problems with spray from the jet hitting the sandstone showed that a remote-controlled mobile monitor was needed at a station 15 m (50 ft) from the face, so the operator would have a clear view of the face and be safely out of the backwash. Crushers. Research on crushing systems to improve efficiency in underground mines is continuing. Final testing of a low-profile, portable crusher for underground applications has begun. A system for handling oversize feed to the crusher was conceived and tested. Underground crushing systems, portable enough to be kept near the face, offer considerable improvement in materials handling because main haulage by conveyor is often less costly. Hoists. Research to increase hoisting efficiency and speed and to reduce energy requirements has led to experimental ore skips. The skips feature guide rollers to improve riding characteristics, bearing improvement at critical locations, and weight savings of about 1.8 t (2 st). An experimental aluminum skip was installed last year at Kerr McGee's Church Rock mine. Performance is being monitored under production conditions. A portable service hoist for low-cost, efficient movement of men and supplies in raises between mine levels was designed, fabricated, and tested on the surface. The hoist has maximum equipment payload of 570 kg (1,250 lb) at

Jan 11, 1983

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

By S. K. Kawatra, T. C. Eisele

Pyrite depression is of great interest in sulfide mineral flotation, where pyrite is a common gangue mineral. Since the floatability of pyrite is a function of the pH and a variety of other chemical factors, pH control is a critical part of sulfide flotation circuits. A wide variety of pyrite-depressing chemicals have been studied and used in sulfide- mineral processing, with considerable success. However, there are certain applications where there are still no satisfactory pyrite depressants, and even when suitable depressants are available, there is always a need for less-expensive reagents. Microorganisms, such as the bacteria Thiobacillus ferrooxidans, are known to depress pyrite flotation. However, the dependence of the depression on the type of organism or on suspension pH is still being determined. In this study, the relative effectiveness of various microorganisms, and the effect of pH, has been examined. Screening tests using microflotation showed that every microorganism tested was capable of depressing naturally hydrophobic pyrite at acidic pH. Larger-scale experiments with two of the screened organisms and two different pyrites showed that microorganisms are very effective depressants at acid pH, but are largely ineffective at neutral and alkaline pH where the pyrite surface is not naturally hydrophobic.

Jan 1, 1994

By Bianca Cruz, Tom Lankiewicz, Kent Sorenson, Karrie Radloff, Elizabeth Deyett, Dayal Saran, Michaeline Albright, Dan Stigers

Biology opens a new frontier for the mining industry. With rising environmental concerns, the need to couple conventional chemical and physical technologies with sustainable approaches is pressing. At Allonnia, we harness microbial processes to create innovative and environmentally responsible technologies with broad applications. The native microbial community (microbiome) remains largely unexplored at most mining sites, unlike the geochemical environment. The exploration of complex biological reactions that could transform mining technology is just starting and holds vast possibilities, spanning bio-cementation, carbon sequestration, ore beneficiation, water mitigation, bioleaching, metals recovery, and more. Allonnia has collected samples from mine sites in Australia, Africa, and North America to characterize the microbiome and uncover the genetic potential present in mineral-rich environments. We are evaluating microbial metabolites that selectively solubilize gangue from various ores. In addition, biological reactions hold promise as tailings stabilizers. Our early efforts illustrate exciting prospects for harnessing biology’s potential in mining.

Feb 1, 2024

By M. H. Pettibone

During the past decade, the size of grin- ding mills has steadily increased. Mills 11 m in diameter with 9 mW motors have been installed with even larger units on the drawing board. The rising costs of energy and labor have spurred interest in improving efficiency while reducing capital investment and operating labor. Autogenous and semiautogenous grinding have experienced renewed interest as efforts to reduce operating and capital costs have increased.

Jan 1, 1981

By G. F. Weaton

1.1 The purpose of this paper is to show the way by which estimates are made of the tonnage and grade of iron ore and taconite reserves of Minnesota. 1.2 The procedures include those of estimating the open pit reserves of: (a) Natural iron ore, and (b) Taconite 1.3 The methods of estimation which will be discussed are primarily based on the information from exploring iron ore deposits. They consider the geology of the deposit as well as the contained mineral of potential value. 2.0 Some geologic, engineering, and economic principles. 2.1 Ore 2.11 "In the broad economic sense, and from a legal standpoint as well, ore is mineralized rock, which under appropriate conditions of time, space, technology, economics, and politics, can be mined, processed, and made to yield a saleable metal , or other mineral products at a profit."(Parks, 1957) Stated differently, metallic ore is rock material from which presently known methods of beneficiation, a merchantable concentrate, suitable for use in the manufacture of metals at a profit, can be produced. Crude ores as low as 0.38% metal, as in the case of copper and even lower in the case of the precious metals.

Jan 1, 1985

By Robert B. Crookston

Oil from shale has been produced in foreign countries for more than a hundred years; however, except for short-lived, small operations, no commercial quantity of oil shale has yet been produced in the United States. Efforts to develop a viable oil shale process have been underway domestically for many years. At the present time, with the need for energy so urgently upon us, almost a dozen development ventures are underway or planned in Colorado and Utah. Of these several ventures, only Colony Development Operation has completed the development, testing and design of a ready-to-go 50,000 barrel per day com¬mercial project. Colony is a joint venture of the Atlantic Richfield Company, Ashland Oil Company, Shell Oil Company and The Oil Shale Corporation, more commonly known as TOSCO. TOSCO is the exclusive licensor of the TOSCO II retorting process and other oil shale technology, which includes mining, crushing and spent shale disposal techniques. This paper will deal, however, with only the materials handling aspects of the commercial oil shale operation. Oil shale handling for this infant industry is unique in that an understanding of the physical characteristics of the ore and the demands on material handling to the plant must he understood. Colony Development has completed ten years in the research and development of techniques and processes for mining, crushing and retorting raw oil shale and the disposal of spent or processed shale. A great deal has been learned about oil shale, in many cases confirming our intuitive analyses and the work of others, but more specifically we have brought it all together to a point where equipment performance and the specifications have been established and a design for the first commercial plant is now mature.

Jan 1, 1975

By Stephen L. Chryssoulis

The detection and quantification of invisible gold by microbeam techniques is discussed. Ion probe microanalysis is used to quantify the gold content of individual sulphide, sulpharsenide and oxide particles with a detection limit of 0.2 ppmw (g/t). The proton microprobe is used to determine the gold concentration of gangue minerals with a detection limit of 2 - 4 ppm. Using these techniques complete mineralogical balances for gold are obtained to assist in the process selection and optimization. A total of twenty gold and gold-bearing ores have been examined. Selected examples are presented.

Jan 1, 1990

By Kevin R. Burns, William A. Depree, John J. Jansky

This paper presents some of the work associated with the reduction of employee exposure to diesel and blasting contaminants at an underground salt mine. The purpose of the paper is to outline the procedures recommended in resolving the problems associated with these contaminants. The first stage consists of a complete mine ventilation survey. The purpose of the survey is to identify any problems in the mine. The survey consists of air quality, air quality and ventilating pressure measurements taken throughout the mine. After completing the survey, the information is analyzed to identify problem areas and the possible causes. All available solutions to reduce the levels of contaminants are then explored and evaluated for feasibility. The PSU Mine Ventilation Simulator is then used to accurately simulate possible changes to the ventilation system. These ventilation projections are a useful tool to illustrate to the company and union personnel the possible benefits of various ventilation changes. This paper will illustrate the phases involved in making important and sometimes expensive ventilation decisions. Through the cooperative efforts of MSHA, company and union personnel, the levels of contaminants have been reduced by approximately 200 percent. As a result of these ventilation improvements, the company can now safely increase production approximately 25 percent.

Jan 1, 1987

By Kristin Hemlein

Mining project development, permitting, environmental regulatory and compliance issues in Uzbekistan and the CIS are every bit as complex as those in the western world. The vast array of environmental permitting, monitoring and reporting regulations for mine project development and operation in the CIS are based on existing Soviet environmental regulations and policies which have remained in place after these countries gained independence from the former Soviet Union. The approach to mine project permitting in the CIS differs from the western world. Similar pre- feasibility, baseline data collection, and environmental monitoring requirements allow the project proponent to coordinate preparation and submission of documentation to support project permitting for Uzbek regulatory requirements with environmental requirements imposed by financial institutions and western environmental compliance structures. Implementation of generally accepted western environmental best management controls and monitoring into mine design, construction, and operation will not, however, ensure automatic compliance with Uzbek environmental regulations. Uzbek environmental compliance requirements that differ from western requirements include: 1) development and maintenance of an environmental database constructed specifically to address annual, biannual and quarterly statistical reporting requirements for emissions of "environmental pollutants" from the facility into air, surface water, ground water and soil; 2) preparation and submittal of specific permits for water utilization, hazardous waste storage and disposal, landfill construction and operation, and stack emissions inventories; and 3) procurement of approvals from the Uzbekistan State Committee for Nature Protection (generally analogous to the US Environmental Protection Agency). This paper outlines and summarizes the regulatory requirements for mine site permitting and the procedures for environmental monitoring and reporting during mining operation in Uzbekistan and the CIS.

Jan 1, 1997

By L. T. Larson

Had the blank on the Abstract form been sufficiently spacious a more appropriate title for this paper would be: Neogene Tectonism, Magmatic Activity and Hydrothermal Precious Metal Mineralization in Anatolian Turkey; an Analog with the Basin and Range Province of the Western U.S.? Like the alternative title no thing in Turkey is simple. Its history is long and convolute; its culture fascinating; its metallogeny diverse and its geology very complex. This paper will focus only on the geology of western' Anatolia and the precious metal potential of this third of Turkey. The argument is in the article but to save the reader time and suspense I'll put my conclusions up front- the potential is great and the possibilities exciting.

Jan 1, 1989

By Kevin A. Foo, Joseph L. Young, William W. Reid

The title of this paper is "Designing Very Large Bio-oxidation Plants". To our knowledge, only one such plant has been designed and built to date, and that is U.S. Gold's Tonkin Springs plant in Nevada. This plant was commissioned in Spring of 1990 and operated for a short time successfully as a bio-leach plant but U.S. Gold did not have the financial strength to overcome the consequences of construction delays and increased capital cost. The plant has temporarily been 1 put on a standby basis. Recently, < > a potential joint venture between Tonkin Springs Gold Mining Company and Homestake Mining was announced. Homestake will operate the mine with the technology and subsequent improvements would be co-owned by both companies. This paper is not a "how to" type publication because we feel that such an approach could be dangerous if used improperly. Rather, we discuss some of the important aspects of process selection, testing and design that need attention, and some of the lessons learned to date. As with all developments, improvements and new knowledge will accrue as more companies use bio-oxidation technology. The Tonkin Springs plant is fair evidence that bio-oxidation has "arrived" as a technology, and that successful design and operation of plants treating greater than 1000 t/d of feed is possible.

Jan 1, 1990

By Jon A. Hummer, MICHAEL R. SHAHAN, Aleksandar D. Bugarski, Shawn Vanderslice

Occupational exposures to respirable dust and submicrometer aerosols emitted by diesel-powered equipment are a health concern for underground mining operators and regulators. A study was conducted in an underground mine with the objective to identify, characterize and source apportion airborne aerosols at the setup face and recovery room during longwall move operations.