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By M. Karmis, S. K. Weisiger

The traditional method for training personnel in the mining and other heavy industries has been face-to-face, either via a lecturer in a classroom or through an apprenticeship. With the advent of applications tools such as video, computers, and the Internet, however, a much broader range of training delivery methods is available. Especially exciting are the broad capabilities of multimedia packages that combine the best features of numerous delivery methods. Applying multimedia environments in training holds great potential, especially when there is considerable difficulty in reconstructing real training environments. The authors discuss various delivery methods currently used in training employees, including perceived advantages and disadvantages of those methods. The authors then discuss and evaluate current computer-based training efforts of the mining industry and present an example of a multimedia training tool.

Jan 1, 2001

By Ralph Spickermann

UK Seabed Resources (UKSR) signed a manganese nodule exploration contract with the International Seabed Authority on 8 February 2013 for a 58,000 km2 tract on the eastern edge of the Clarion Clipperton Zone (CCZ). UKSR is a private company based in the United Kingdom and established primarily to develop the commercial potential of the CCZ deposits. This is the first of many anticipated regulatory, market and technical milestones that are requisite for (1) environmentally responsible commercial scale production of nodule derived metals and (2) generation of revenue through their sale in the global commodities market. This presentation will describe the progress made to date in this effort and an industry-based perspective on the tasks and challenges that may lie ahead.

Sep 1, 2014

M.S. Azun I have many objections to the content of the author's paper. Before discussing it, however, I would like to repeat the property of semivariogram function. Second order stationary properties of regionalized variables (ReV's) such as semivariogram function y(h) are perfectly known in geostatistics. Also, the kriging equations in the language of mathematical statistics using second order stationary properties are well understood. However, the way to use the sample (estimated) semivariogram function in any one of the kriging procedures is vague. The sample semivariogram function is given as follows: [ ] where N is the total number of samples, Xi is the sample value at the i - th location, Xi+h is the sample value at the i + h - th location, and h is the distance among the samples. An estimation variance of sample semivariogram function of first lag is smaller than that of higher order lag. The theoretical semivariogram function reaches the variance of samples asymptotically. But this is not easily observable because of the larger variation involved in the estimate of semivariogram function. In general, an estimation procedure is done for h = 0, 1, 2, up to the greatest integer less than N/2, even though sample semivariogram function can be computable through N-1. After estimating semivariogram function, the critical question of how to model sample semivariogram function arises. As seen in the above equation, sample semivariogram function is discrete and can be smoothed by the model being selected. Therefore, modeling of sample semivariogram function is the most important step in geostatistics. It not only smoothes a discrete function but also affects the results of the kriging procedure. When the only aim is to model the semivariogram function, which is the basic point of the author's paper, one can employ any fitting techniques, such as curve fitting, or any arbitrary functions, which are called submodels in the paper. The term "arbitrary function" is used rather than "submodel" because there is no basic understanding of developing them. The author suggests that the sum of those submodels can also be used for the modeling of sample semivariogram function. The combination of any arbitrary functions brings many problems instead of giving an insight of the domain structure considered. The author used two arbitrary functions and the nugget effect in response to sample semivariogram function (Fig. 10). For the same example, he stated that the parameters involved in the mixed arbitrary function model can be accepted when the discrepancy between sample semivariogram function and the model is small visually. For verifying the fitting behavior of any selected model, one should not be contented with the visual satisfactory. Some statistical measure such as goodness of fit has to be used. The author's practice is no more than an exercise in curve fitting without any fundamental understanding or conceptualization of the underlying physical mechanism. Furthermore, the selection of any model is not an easy task if the purpose is the search for the "best" response to the observed second order properties of ReV's. I suggest that the Markovian model (Azun, 1983), on the basis of a theoretical understanding of underlying mechanism, which gives more information about the occurrence of regionalized variables, is used to respond all properties of ReV's. There are a lot of problems for modeling of one-dimensional sample semivariogram function. Thus, it is not appropriate to go to higher order dimensional sample semivariogram function modeling. In the meantime, I would recommend that one can connect the values of standardized sample semivariogram function rather than simple values of semivariogram function in the two-dimensional estimation. The standardized values can be computed in dividing the semivariogram function value by the number of sample pairs involved in each lag regardless of the directions. In conclusion, geostatistics is an interdisciplinary area in mining that uses the principles of mathematical statistics. Thus, it should not violate any probabilistic and statistical rules. When Matheron was developing the theory of geostatistical study in the early years of geostatistics, many mining people had a reservation accepting the geostatistical tools. However, this does not mean that we, the geostatisticians, might try to convince those people using some "strange" tools or rules as some authors implied (Baafi and Kim, 1984). Instead, we have to develop and explain the geostatistical tools staying only in the framework of statistical concepts and properties. References Azun, M.S., 1983, "Stochastic Process Modeling of Spatially Distributed Geostatistical Data," Columbia University, Ph.D. Thesis. Baafi, E.Y., and Kim, Y.C., 1984, "Discussion - Comparison of Different Ore Reserve Estimation Methods Using Conditional Simulation," Mining Engineering, Vol. 36, No. 3, p. 280. Reply by J.M. Rendu The interactive method proposed by Rendu allows practitioners to develop semivariogram models that take into account not only the numerical information obtained by sampling, but also highly significant additional information that often cannot be quantified. The geology of the deposit - including hypotheses concerning its genesis, sampling methods, assaying methods, and mathematical methods used to calculate the semivariograms - all have an influence on the numerical results obtained and on how these results should be interpreted. If all the information concerning the spatial distribution of values in a mineral deposit was contained in the sample values, it could be argued that statistical techniques alone would produce optimum models. However, this is rarely, if ever, the case. Methods that allow the user to take into account his experience and his geologic understanding of the deposit should not be rejected for the sake of theoretical statistical purity.

Jan 11, 1985

By Dale S. Hursh, William A. Brooks

Introduction US dependence on external energy sources is dangerous because of unstable political situations existing in key energy exporting countries. So, recent national energy policies call for increased reliance on domestic energy sources. Coal ranks as the most feasible domestic energy source due to its abundant reserves and continental distribution. But to efficiently extract these coal reserves, huge sums of capital funds are needed. Due to the depressed economy, lenders of capital funds are forced to be more stringent with loan applications. This results in fewer loans granted. In many cases, it is uncertain if funding can be obtained. Furthermore, the greatest level of domestic mine financing is expected to be in the coal sector. Demand for capital in the domestic coal industry is anticipated to increase 80% by 1990. The Chase Manhattan Bank in New York warns that these future needs cannot be met by the present capital markets. This article analyzes the current and expected situations of the capital markets available to the domestic coal industry, including: • current and expected future types of financing used in the domestic coal industry; • problems the domestic coal industry may encounter as it seeks capital; and • the future availability of capital funds as concluded from analysis of the first two items. Background Information Regardless of industry, all projects or ventures can be divided into four basic stages: generation; evaluation; selection; and execution. Within the mining industry, one can break down these stages to draw a clear picture of mine development, as shown in Fig. 1. Each successive stage has a corresponding risk level. This risk level defines the type of financing available to the mine operator. Mining Venture Risks A coal mining venture can be characterized by its unique blend of technical and financial risk. As the mine moves through different development stages, varying proportions of each of these risks are encountered. It is these risks that the lender evaluates to determine project suitability. For a coal mining venture, the major complexities generally occur with the technical risk. These include: • quantifying the coal reserves: • assessing the feasibility of the mining method; and • evaluating the design of the wash plant. The reserve risk is gauged by the amount of measured, mineable, and saleable reserves. The greater the latter amounts, the lower the risk. Secure title to the reserves plus title for any surface areas required are also of concern to the banker. Feasibility of the mining method and evaluation of the wash plant design should verify that the project can be completed according to the engineered spec-

Jan 9, 1982

Queensland?s underground coal industry, as a whole, has arguably the best gas monitoring systems in the world. Each mine utilizes real time, tube bundle and onsite ultra fast gas chromatograph systems. Queensland?s mining legislation has specific requirements for mine gas monitoring but there is no requirement for all three techniques. Industry has however identified the need for all three and adopted this as a standard, resulting in over sixty thousand gas results collected each day. Automated monitoring systems are programmed to alarm for gas concentrations, gas ratios and explosibility. These alarms are then used to initiate predetermined actions to take control of the situation and prevent the compromise of safety to workers and the loss of resources. Dedicated software packages have been developed to assist in the interpretation of the large volume of results generated. The real time systems are used for real time warning, essential for incidents such as belt fires. Tube bundle systems suit long term trending used for identification of the onset of spontaneous combustion or for the determination of explosibility during the routine sealing of worked areas. Gas chromatograph analysis is used to provide a complete analysis and provides results for hydrogen and ethylene, key gases used in the assessment of spontaneous combustion. It is also crucial during significant spontaneous combustion events and coal fires to use gas chromatography to determine the explosibility status of the underground atmosphere otherwise the severity of the situation is likely to be under estimated. This paper outlines the need for all three techniques for assessing the underground status and outlines advantages and disadvantages of each.

Jan 1, 2009

By M. Javier

This concept paper is presented in the hope of raising the awareness of mankind on the necessity for its peaceful coexistence with nature. It is a food for thought. It takes compromise and sacrifice of people, who will have to learn to curb their greed and move toward a more organic form of prosperity. A nature-friendly sustainability is first step toward the protection of nature that is critical to the mutual survival of mankind and nature. People need the resources from the finite earth to survive and nature needs the prevention of human destruction in order to continue to regenerate and provide. The contemporary notion of sustainability is self-serving. It serves the interest of industry by camouflaging itself to look like nature?s protector. The ?sustainability? concept presented in this paper aims to extend the longevity of the utilization of the limited natural resources for many generations to come. It is an important, responsible first step in creating a healthy sustainability concept that, when implemented, extends the longevity of mankind by the most efficient use of the finite resources on this limited Planet Earth, all the while taking into consideration the increase in anthropogenic activities due to exponential human population growth. This new definition of ?sustainability? has completely different characteristics than its contemporary versions. Nature has its own destiny, rules and principles. Being a part of nature, human society depends on it for survival and must play by its rules and never the other way round as in its initial pretensions. Society should not try to humanize nature, but rather to respect the rule of the nature in a peaceful way of co-existence. When implemented, this new concept of sustainability aims to affect the designs of engineered structures and revolutionize the recovery methods and processing of natural resources, such as mineral resources in the most efficient manner. Finally, this paper intends to stimulate critical thinking and initiate serious discussions aiming at producing a general consensus for the best definition for human society to not only enrich, but to extend its existence. Thus, the spirit of this new definition is pro future generations and environment. KEYWORDS: Sustainability Definition, Nature, Geomímic, Deproduction.

Feb 27, 2013

By J. C. Poulos

The West Elk Mine is located near Somerset, Colorado approximately 70 miles southeast of Grand Junction, Colorado and 72 miles southwest of Glenwood Springs, Colorado on state highway 133 (Figure 1). The West Elk Mine was opened January 20, 1982 as the Mount Gunnison #1 Mine operated by the West Elk Coal Company, a division of ARCO Coal. In the early 1990?s ARCO changed the mine name to West Elk Mine and the operating company was renamed Mountain Coal Company. Arch Coal, Inc. purchased the West Elk Mine in 1998. West Elk Mine has produced coal from three different seams. Coal was first mined from the F Seam, the upper most seam in the stratigraphic sequence, from 1982 through 1991. Coal was produced from the B Seam, the lower most seam, starting with continuous miners in 1991 and transitioning to longwall mining in 1992and continued on through October 2008. The development of the E Seam, which is the middle seam in the stratigraphic column, started in 2004 with longwall production commencing in 2008. The ventilation conversion from exhausting to forcing for the E Seam portion of the West Elk Mine was implemented in late October 2009.

Feb 27, 2013

By Mohamed A. Younis, Paul J. Headland, Paul H. Madsen, Vojtech Gall

INTRODUCTION A 100 ft long, 20 ft high and 18 ft wide NATM tunnel was excavated through grouted clean sands beneath a busy city street, including a variety of existing utility lines. The new tunnel associated with a hospital expansion will serve as a pedestrian tunnel connecting a parking structure with a new hospital facility. Tunnel construction started on December 15, 2005 when drilling for the grouting program started and was completed on May 26, 2006 when the tunnel final lining was completed. The tunnel was constructed by Kiewit Construction Company as a tunnel subcontractor to The Christman Company who is constructing the hospital facility for Spectrum Health in Grand Rapids, Michigan. URS was the project designer. GallZeidler Consultants, LLC were the contractor’s NATM consultant. PROJECT DESCRIPTION The Michigan Street Pedestrian Tunnel is a component of the Michigan Street Development located along the north side of Michigan Street NE between Coit Avenue NE and North Division Avenue in the downtown area of the Grand Rapids, Michigan. The Michigan Street Development includes a parking deck and four new towers to be constructed over the proposed parking deck. The tower planned furthest east is being developed by Spectrum Health as the Lemmen-Holton Cancer Pavillion. The purpose of the pedestrian tunnel is to connect the proposed Lemmen-Holton Cancer Pavillion with the future Spectrum building to be located on the south side of Michigan Street NE. The southern end of the tunnel was constructed with a bulkhead until the future Spectrum building is constructed at which time interconnection will be required. The tunnel site plan and profile are shown in Figure 1, Site Plan, and Figure 2, Tunnel Profile. Several challenges were faced during the design and construction of the Michigan Street Pedestrian Tunnel. These challenges included compressed design and construction schedule, maintenance of traffic and protection of old underground utilities. The tunnel was being constructed as part of the Michigan Street Development and coordination with other concurrent construction activities was required. The tunnel was constructed within a specified window of time to allow other associated construction activities to take place without compromising the overall project schedule. The design started in June 2005 and construction was completed by June 2006.

Jan 1, 2007

By T. C. Pool

Physical and chemical conditions permitting, in-situ leaching (ISL) of uranium offers a variety of advantages over conventional production methods including less surface disturbance and less solid waste. Commercial production of uranium by in-situ leaching techniques was initiated in 1963 in the Shirley Basin of Wyoming by Utah Construction. On a world-wide basis, ISL uranium production amounted to about 13.2 million pounds U3O8 in1999, approximately 16% of world output. Both acid and alkaline systems are used, the selection of which is primarily dependent upon groundwater quality and related reclamation requirements. ISL offers low capital costs per unit of annual capacity and is particularly flexible in adapting to changing market conditions.

Jan 1, 2000

By Rex E. Loesby

The marble deposits of Yule Creek were first discovered in the late1870s. Minor quarrying occurred between that discovery and the early 1900s. Major development occurred in 1905, when Channing Meek, with some help from the Rockefellers, raised $3 million to develop the Colorado Yule Marble Quarry. That is $50 million in today’s dollars. Some of the words used to describe the marble deposit were “gigantic, remarkable, flawless and immense.” Boosters proclaimed, “The marble age is here.” Obviously, dreams were big for Marble.

Jan 1, 2003

By D. Brosnahan, J. Gathje

Newmont Metallurgical Services (NMS) recently acquired a Scanning Electron Microscope (SEM) with a JKMRC/FEI Mineral Liberation Analyzer (MLA). With the MLA software package, raw particle image and X-ray data can be converted into particle mineral maps and bulk and liberation data can then be calculated for minerals of interest. This type of quantitative mineralogical data can then be used for a wide variety of applications. Ore characterization with MLA can be carried out for existing or processing plants in development. MLA characterization of laboratory test products provides valuable liberation information that assists the research metallurgist in better planning and developing process treatment options for various ore types. This paper describes the use of MLA characterization in a copper flotation test program where the use of various testing options for arsenic depression was being evaluated.

Jan 1, 2007

By T. W. Beck

Overexposure to respirable dust remains a widespread health hazard to roof bolter occupations in underground coal mines. Recently implemented mist drilling technology was evaluated for its effectiveness in controlling respirable dust exposures for roof bolting personnel. This work presents the findings from NIOSH field and laboratory studies comparing respirable dust levels on mist drilling roof bolter machines to dust levels measured on machines using a conventional vacuum drilling system. Gravimetric and instantaneous respirable dust samples were collected for multiple drilling cycles. These dust measurements were used to assess the potential dust control capabilities relative to conventional drilling. Controlled laboratory tests found 0.3 mg/m3 more respirable dust with mist drilling than with the conventional vacuum method. A separate field investigation of the two techniques observed higher dust levels around the mist bolting machine.

Jan 1, 2008

By Seal. Thom

Large heap leach operations around the world contain significant under-leached metal values that present recovery challenges to operators. The first challenge is to find the location of the highest inventory. High resolution resistivity ? has proven sensitive enough to detect such zones in the interior of heap leach pads to target treatment or re-leaching. Newmont Mining Corp. has adapted the high pressure fracturing technology, used in oil wells to stimulate select zones in heap leach pads to add reagents in 3-D for re-leaching, changing zonal chemistry for improved recovery and heap closure. High Resolution Resistivity ? is able to subsequently monitor injected solution flow and determine directional permeability during Hydro-Jex stimulation. The combination of these technologies has shown strong economic success, for selecting targets in the heaps and monitoring solution application. These technologies are now available to the mining industry for adoption.

Jan 1, 2008

By M. Perolo, A. Contini, E. Ramelli, G. Borgonovo, L. Locatelli

This paper presents the ground settlement monitoring system used during the construction of two tunnels bored by two EPB TBMs, beneath the existing and active railway embankment in Bologna (Italy). The tunnels run close to large buildings and beneath bridges and other infrastructure. Data are collected from remote total stations and from electro levels installed directly on the railway tracks. The automated monitoring system acquires and analyses data then sounds an alarm in the event that there is a problem. Alarms are sent out in case of excessive tilt or settlement. Data is provided through a dedicated web application for multiple-party access, to gather, manage and store monitoring data.

Jan 1, 2007

By J. Burgess Winter

It is an honor to present the lecture in honor of Daniel C. Jackling, the developer of the technology of copper mining that we continue to use 100 years later. He made a dramatic breakthrough in the early part of this century in the development of bulk-mining methods for large, low-grade porphyry copper-sulfide ore bodies. At Magma Copper, we are particularly proud that the Jackling Award states we have "made significant contributions to technical progress." Before Jackling's time, copper mining had exploited with primitive equipment very high-grade underground ore bodies and high-grade open pits. During the 20th century, the situation changed. Three significant innovations occurred within about 10 years around the turn of the century. In 1903, Jackling's concept of large-scale mining with steam shovels and rail haulage was implemented at the Bingham Canyon mine in Utah. Eighty years after the introduction of rail haulage, the mine converted to truck haulage with large-capacity high-efficiency haul trucks and reduced the stripping ratio from 3.5:1 to less than 1:1.

Jan 1, 1995

By Brendan Henry

The Canada Line is a 19km long automated light rapid transit system with 16 stations in Vancouver, BC, Canada. The Concession was awarded to InTransitBC to design, build, partially finance, operate, and maintain the system for 35 years. The project must be complete by November 2009 to be ready for the 2010 Winter Olympics to be held in Vancouver and Whistler, BC. The bored tunnel section consists of 2.45 km of twin bored tunnel and 3 stations. The station work is limited to the excavations and temporary support necessary to facilitate the bored tunnel works. A joint venture between SNC-Lavalin Constructors Pacific and SELI (SSJV) has recently completed the design and construction of this section. Work for the bored tunnel commenced in November 2005 with shoring and excavation works for the tunnelling operations pit that will become Olympic Village Station and will be completed in the spring of 2008. The tunnels were driven with a 6m diameter Earth Pressure Balance Tunnel Boring Machine (EPBM) and lined with 250mm thick, 5.3m diameter precast concrete segments. Seven hundred and fifty meters of each tunnel were driven through glacial and interglacial deposits of sand, silt, and clay with granitic boulders. The paper discusses the challenges faced in negotiating these soils which contained unforeseen geological conditions. These conditions were overcome by developing a systematic approach to Risk Management that included thorough risk assessments, regular risk management meetings with the participation of two of the world?s leading EPBM experts, Professor Eisenstein and Professor Kovári, and by the ability of the construction team to effectively analyze and mitigate problems.

Jan 1, 2008

By N. R. Allen, J. D. Steenkamp

Oxidative roasting is applied on an industrial scale to beneficiate ilmenite concentrates from South African East Coast heavy minerals deposits - the aim is to increase the magnetic susceptibility of ilmenite to allow magnetic separation from chromite. The intention of this paper is to give researchers new to the field an overview of the beneficiation of ilmenite through roasting and magnetic separation, touching on the relevant fundamental aspects of magnetism.

Jan 1, 2005

By John Reilly

Traditional methods of project procurement of have remained virtually unchanged in the U.S. infrastructure construction industry for more than 50 years. The traditional method, Design-Bid-Build (DBB), uses a two-step process that separates planning and design from construction. Design is generally done by the public agency and their consultants and the subsequent construction contract is procured from the private sector, almost always by a “low-bid” approach. This method has worked well for many projects, delivering quality work for the lowest bid price. This is particularly true for those projects where the work, and the public agency’s management procedures, are well understood by the contracting community and there is relatively low uncertainty in the work or conditions, particularly geotechnical conditions for underground construction. However, concerns exist with the DBB process. It is time consuming because all planning and design work must be completed prior to beginning any construction work and it is of concern for complex or large projects, plus those with significant risk, where the separation of design and construction, in conjunction with pressures resulting from the low-bid environment, often result in substantial cost and schedule increases. Frequently, these increases occur in a non-productive, inefficient, adversarial work environment leading to claims, disputes and costly litigation (Quick 2002).

Jan 1, 2007

By R. M. Owens, J. F. Lupo

The Shirley Basin Uranium mine, located in southeastern Wyoming, USA, was an open pit mining operation consisting of a series of several open pit mines excavated into poorly consolidated sandstones, siltstones, and claystones. Since the initial open pits were developed in 1969, slope failures have plagued the mine and mining operations. These slope failures have persisted into the current mine reclamation period. When the mine was first developed, the open pit slopes were designed to range between 45 to 55 degrees. Numerous slope failures during mine development required the pit slopes to be redesigned with slopes as shallow as 26 degrees. At present, movements are occurring within the open pits on reclaimed slopes that are shallow as 12 degrees. Several detailed slope studies were conducted at the mine in the early 1970s. These studies, combined with more recent geotechnical investigations, provide a unique detailed history of pit slope failures on shallow slopes. This paper presents an evaluation of the slope failures at the Shirley Basin mine, highlighting important mechanisms causing slope failures on very shallow slopes. The evaluation demonstrates important key parameters for shallow slope design.

Jan 1, 2001

By Drupad B. Desai, Bruce Chang, Jay L. Merritt

This paper reviews difficult ground conditions encountered along the alignment of large-diameter sewage tunnels for the City of Los Angeles. It offers a detailed one-of-a-kind solution to a unique problem for shallow urban underground tunnels in a seismic zone, using state-of-the-art materials, technology, and equipment. The following topics are discussed in detail: • Geotechnical Design consideration for tunnel traversing through an active fault zone. • Seismologist evaluation of possible fault-offset problems where a fault zone crosses the alignment, in the event of an earthquake of moment-magnitude 6.5. • Probability analysis regarding "recurrence interval." • Structural design of tunnel subjected to displacement, subjected to axial elongation or shortening, and capable of rotational freedom. • Special joint details.

Jan 1, 1989