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By T. R. Ellis

A number of important international events took place in 2001 in the development and evolution of mineral valuation standards internationally. In Canada, the CIMVal Committee released a draft discussion paper for public and industry comment on principles to guide the development of the planned Canadian mineral property valuation standard. The International Accounting Standards Board (IASB) received comments on its Extractive Industries Issues Paper. IASB will decide whether the financial statements of public mining and petroleum companies will be allowed to provide the value of mineral and petroleum assets on a current value basis instead of an historic cost basis. The author led the Extractive Industries Task Force of the International Valuation Standards Committee (IVSC) in developing its submission to IASB. IVSC intends to develop an extractive industries valuation section for its International Valuation Standards, which could support the planned IASB standard. In Australia, AusIMM has carried out an in-depth review of its highly regarded VALMIN Code. The AusIMM's MICA subdivision organized the VALMIN ‘01 Conference in Sydney, Australia, with a range of international and current issues papers published in the VALMIN ‘01 book. Considerable support for the IVSC initiative was evident at this conference. The results of the review of the extractive industries submissions to the IASB are expected to be released in early 2002. The CMMI Congress in Cairns, Australia in May 2002 is likely to prove to be an important forum for continued discussion of the development and implementation of international standards and qualifications for mineral valuation. The outcomes and implications of these events are discussed.

Jan 1, 2002

By G. T. Lineberry, W. J. Wiehagen

A Paradigm Shift As market economists, mine managers are interested in "staying in business" and even "prospering." Bottom-line results are the "order of the day." Concern for bottom-line results invokes questions such as: How much was produced? At what cost? And, was anyone injured? While these questions will always carry everyday emphasis at the mine, they are fundamentally lacking in that they often appear, especially to lower levels of management and to the production worker, as preeminent concerns. Driven by market economics, many organizations have decentralized, outsourced, downsized, restructured, and formed new coalitions. Investments in new technology and concentration on productivity have been part and parcel with these changes, contributing to improvements in both safety and efficiency. A reason for (and, perhaps a result of) these improvements has been the development of a highly experienced and flexible work force. These changes in mining present an interesting opportunity to modify a few paradigms about work life in general, and perhaps a few paradigms about how we invest in the miner, in particular. Studying these issues now might offer some interesting opportunities for the future, as the foundations for the next generation of mine workers are laid. With the average "experienced" U.S. miner five to fifteen years from retirement, perhaps a key determinant of future success in the world market might be how well we make the transition from today's work force to the work force of tomorrow. We can ill afford to wait a few more years to tap into the special knowledge residing within a veteran mining work force. The WCPM work Crew Performance Model, see pp. ) is one approach to defining, capturing, and transferring this expertise.

By P. -E. Boileau, P. Marcotte, Y. Aldien, S. Rakheja

A number of biodynamic models of the hand-arm system have evolved on the basis of measured driving-point mechanical impedance (DPMI) responses to facilitate analyses of the coupled hand-tool system [1]. The parameter identifications in such models are based upon minimization of an error function of the model and the target impedance data, which may not yield a unique solution. Consequently, a number of model structures and parameter sets could be realized that would equally satisfy the target curve. Moreover, the vast majority of the reported models exhibit acute deficiencies due to excessive static deflections of model masses, presence of a low frequency mode and very light masses in the order of 1.2- 4.8 grams. The models also do not characterize the dependency of the biodynamic responses on many factors, namely the hand forces, hand-arm posture and vibration intensity. This study aims at development of a hand-arm biodynamic model with considerations of the hand forces, and both the DPMI and power absorption measures, to enhance the uniqueness of the model. Methods Two different model structures are chosen for identifying the model parameters on the basis of measured DPMI and absorbed power characteristics of the hand-arm system under zh-axis vibration over a range of hand-grip and push forces. Owing to the strong influence of the hand-handle coupling forces, the models were initially derived for fixed hand forces, namely 30 N grip and 50 N push forces, as suggested in the ISO 10068 standard [2]. The equations of motion for the model are formulated and solved to compute both the DPMI and absorbed power responses. A constrained minimization function comprising weighted errors of both the DPMI and absorbed power is formulated and solved to identify the parameters. Alternate functions corresponding to different combinations of hand forces are then applied to identify hand-force dependent model parameters. Variations in the model parameters are investigated as functions of the grip, push and coupling forces through linear regression analysis. Regression-based models are formulated for deriving the hand-handle forces dependent model parameters. The validity of the model is also examined under selected combinations of hand forces. [ ]

Jan 6, 2006

The Golden Cross Mine will be the first underground gold mine in New Zealand to operate since 1952. The development plans, along with the conditions and circumstances presently found in the now ongoing mine development, will be discussed as well as a brief review of planned stoping activity and stoping results to date.

Jan 1, 1991

By B. J. Moore

This publication contains routine analyses and related source data for 528 natural gas samples from 21 States collected during calendar year 1965 as part of a continuous survey of the United States for occurrences of helium in natural gas. This survey has been conducted by the' Bureau of Mines since 1917. The analysis published herein were made by mass spectrometer and a special helium analysis apparatus, which are described in Bureau of Mines Bulletins 4863 and 576.4

Jan 1, 1966

By B. J. Moore

This publication contains routine analyses and related source data for 528 natural gas samples from 21 States collected during calendar year 1965 as part of a continuous survey of the United States for occurrences of helium in natural gas. This survey has been conducted by the Bureau of Mines since 1917. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus, which are described in Bureau of Mines Bulletins 4863 and 576.4

Jan 1, 1966

By Jueun Lee, Jong-Hwa Yoon, K. Rider, Bernard J. Martin

Whole body vibration is known to affect movement accuracy [1], however little is known about changes in the organization of movement and movement strategies used to limit the influences of perturbations. The specific aim of this work is to analyze the motion and coordination of upper body segments of seated operators performing reaching tasks under whole-body sinusoidal vibration exposure and simulated vehicle ride motion. The long-term objective is to model reach coordination and predict the dynamic behavior of the upper body motion under vehicle vibration exposure. Method The reach task consisted of pointing with the right hand index finger to targets located on touch screens placed in front of the subject, 45° overhead and 90° to the right in the mockup cabin of an HMMWV placed on a 6 DOF ride motion simulator. The task was performed under stable (no vibration) and vibration (sinusoidal vibration or simulated ride motion) conditions. A motion capture system was used to record kinematic data of reflective markers to recreate body link trajectories. Joint angles (torso, shoulder and elbow; Figure 1) were then computed using quaternions. Coordination between body links was defined as a) the joints angle-versus-angle relationships between the upper arm and lower arm, and b) the joint motion onset relationships between torso, upper arm and lower arm in the time domain. Results Angle–versus-angle relationships. The relationship between upper arm vs. lower arm angle and torso vs. upper arm angle for a far forward reaching movement in the stable (solid lines) and vibration conditions (dotted lines) are illustrated in Figure 2. Fig 2A compares the control condition with a 4 Hz lateral vibration while Fig 2B compares the control condition with a 6 Hz vertical vibration. It appears that under vibration exposure the reduced upper arm extension is compensated by an increase in torso flexion. This effect is seen in the last phase of the movements (encircled areas). In addition, the lower arm extension is delayed under 6 Hz vertical vibration (Fig 2B left panel). Time of joint motion onset. The timing relationship between torso, upper arm and lower arm is largely a function of the target to be reached. Examples of delays between body links are illustrated in Figure 3. The control condition is compared to a 6 Hz vertical vibration for three

Jan 6, 2006

With commodities suffering dramatically low real prices, mining business margins are under intense scrutiny. Unfortunately, management systems developed early this century for manufacturing are driving counterproductive behaviours that choke productivity. The paper and presentation will explain this and present a proven methodology for increasing productivity. This will be supported by operational examples from Australian and American mining management to demonstrate the importance of modern business performance measurement and analysis systems. It will explain the importance of management systems in driving organisational change to sustain superior productivity and margins. The paper will explain why many executives and managers confuse production (a measure of volume) with productivity (which measures efficiency and effectiveness). It will explain how this and other counterproductive managerial and operator behaviours and attitudes are driven by traditional business management systems exacerbated by managerial and consulting fads. The paper will begin with the simple principle that to improve results one needs to first improve the process producing the result û and will show how this is often violated. Improving productivity then boils down to:accurately identifying opportunities using sound, modern measurement, analysis and reporting systems; methodically improving operating and commercial processes, and changing peopleÆs behaviours and attitudes to sustain changes in practices. The paper will include fundamentals of applying sound measurement and analysis to:processes directly, eg cycle time charts and their impact in cyclical (non-continuous) operations commonly used in rock breakage; drivers of productivity; and process results themselves since correct analysis identifies opportunities accurately. The paper will cover the importance of practical leadership and the need to follow a simple, solid plan for changing systems that drive behaviour. Overall, it will highlight use of modern performance Measurement, Analysis and Reporting systems to drive behaviours and improve margins - without capital investment û and make executive and managerial work easier and more effective.

Jan 1, 1999

By R. H. Wright

This paper describes the design philosophy and methods employed in constructing the foundation elements for the Little Britain Project in the City of London. The Contract is a design and construct package for the foundations of a 3-storey basement which will be built using "top-down" construction techniques and is to be carried out by Fairclough Piling and Marine on behalf of Wimgrove Nominees. The Project includes 8000 sq.m. of diaphragm wall and barrettes 139 No. large diameter piles ranging from 900mm to 3000mm in diameter and up to 45m deep, and 9 No. cruciform barrettes for the heaviest column loads. Major factors influencing the design of these foundations include differential settlement, heave analysis and a fast track construction approach. Little Britain will provide 43000 sq.m. of space in two linked buildings which will bridge a new road joining London Wall to Newgate Street. The foundation contract is well advanced and the building is due for completion in the Summer of 1990.

Jan 1, 1989

By D. N. Bigby

This paper concentrates on ground control innovation in Europe since the first Morgantown conference, mainly from a UK perspective. In particular, it describes the rock engineering and ground control tools developed to address the mine support and design problems associated with coal mining at great depth in areas influenced by previous workings. The differences in approach across the Western European industries are also examined. Perhaps the most significant change in the period has been in the science of coal mine rock mechanics itself, with support design now based firmly on measurement, analysis and understanding. The ground control innovations described here have played their part in increasing the efficiency with which coal is mined and in increasing safety to the extent that fall of ground accidents are now rare.

Jan 1, 2006

By J R. Leeming

Mines require ventilation to ensure an adequate atmosphere for the sustenance of life, and to dilute, render harmless and remove contaminants.This paper describes the developments in the United Kingdom (UK) from natural ventilation, through the introduction of fire and simple fans, to modern fully independent and remotely monitored and controlled installations.CITATION:Leeming, J R, 2017. The history of mine ventilation in the United Kingdom, in Proceedings Australian Mine Vent Conference 2017, pp 271–276 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By H. Y. Sohn, M. K. McCarter, Bradley C. Paul

"A computer model was constructed for bacterial leaching of the major sulfides found in porphyry deposits, including bornite, chalcocite, chalcopyrite, covellite, cubanite, enargite, native copper, pyrite, and pyrrhotite. The model incorporates equations for the sulfide minerals dispersed in the rock matrix. Leaching occurs by reactions with ferric ion diffusing into the rock fragment: Ferrous ion is resenerated to ferric with oxygen by bacteria at a temperature dependent rate. The model keeps track of the net acid generated, oxygen consumed by the bacterial oxidation of ferrous ion, heat generated, jarosite and hematite precipitated, and copper leached. The model was used to predict the rate of copper recovery, heat generation and oxygen demand for a variety of run-of-mine sized porphyry ores. These results were used in the design of a ventilation system and the economic analysis of a modified in situ extraction method that may be cost competitive with conventional copper production involving open pit mining.IntroductionA study was undertaken at the University of Utah to evaluate the technological and economic feasibility of mining copper by a method referred to as Flood Drain Leach Cell (FDLC) mining. Cells 60 by 75 meters in plan and 70 meters in height are created throughout the ore body by a modified Vertical Retreat Mining technique that includes the removal of 25% swell material. The swell material is leached in finger dumps on the surface while the cells underground are bulkheaded, flooded, drained, and artificially aerated to promote bacterial ferric sulfate leaching. Solutions are cycled through several cells to reach pregnant grade of 1 gram copper per liter of solution. These solutions are then fed to an underground solvent extraction plant and then a surface electrowinning tankhouse."

Jan 1, 1988

By Rimas Pakalnis

This paper describes a focus of work presently being conducted at the Rock Mechanics Research Group at the University of British Columbia. The underhand method under consolidated fill ensures a high recovery under an engineered back that is comprised of cemented rock fill and/or cemented paste fill. This method of mining is generally necessary either due to a weak rock mass comprising the immediate back and/or high induced back stresses. A major concern in the design of sill mats is the loading and strengths associated with the overlying sill mat. This paper reviews past practice coupled with present observations and measurements from over ten(10) mines throughout North America. It outlines areas of concern in terms of design requirements.

Apr 1, 2005

A regular general meeting of the Canadian Mining Institute will be held in Vancouver, B. C., on Nov. 26-28. The Council extends a cordial invitation to all members of the American Institute of Mining and Metallurgical Engineers to attend.

Jan 11, 1919

The Sons of Gwalia Mine in Western Australia is situated about 140 miles north from Kalgoorlie in arid country, where supplies of fresh water are difficult to obtain.Mine salt water is used throughout the treatment plant, whilst fresh water for domestic, boiler, and power purposes is pumped from a number of shallow outlying wells. The waters from all wells are constant in character, although they vary in the quantities of salts contained.An average sample of mixed waters gave the following analysis (Gr. per gal.):Sodium chloride 70.82Magnesium chloride 33.03Calcium chloride 26.98Calcium carbonate .. 11.57Calcium sulphate 22.71Iron oxide and alumina 2.10Silica and insoluble 4.58When this water is used in the boilers in its natural state it is scale-forming and intensely corrosive.

Jan 1, 1927

A vital ingredient in ensuring that metals exploration companies, working in the developing countries of thePacific Rim, support the development of national geologists is making such a learning program cost-effective. There is a wide spectrum of learning needed in the development of these explorationists: the technical and conceptual skills to carry out exploration efficiently, the professional and managerial skills to apply the exploration in the work situation, the personal attributes required to manage their exploration effectively, and a company organisation that allows them to learn and use these skills and attributes.

Jan 1, 1995

By Gregory Molinda

Historically, coal miners have known that roof shales can deteriorate in contact with humid mine air, causing massive roof falls and injuries from falling rock. It is critical to recognize rocks prone to weathering and to adequately support these rocks in order to ensure the long-term stability of the openings. In a recent study, NIOSH has used a wet/dry cycling test to determine the moisture sensitivity of over 800 specimens of roof rock from 25 U.S. coal mines. Fireclays and some gray shales are the most moisture-sensitive. Rocks with disturbed bedding, in contrast to flat-bedded rocks, are also more sensitive to water. Black shales are relatively un-reactive to moisture and serve to protect more reactive gray shales above. Mines that have roof rocks with moisture-sensitivity indexes above 40% can experience slaking roof conditions, and many require high coverage surface controls. Three case studies are presented in which the moisture-sensitivity index is correlated to roof conditions underground, and can be used to indicate long term deterioration. Engineering measures are described to control moisture-sensitive roof. In one case, roof screen not only reduces injuries from rock fall but also is shown to reduce roof falls. Keywords: coal mining, roof control, slaking, roof support, rock falls

Jan 1, 2008

By K B. Bowley

This paper covers the application of a systematic maintenance plan by the Plant Engineering Department of Rio Algom Mines Limited, Milliken Division. The plan established the function of work study, developed and installed formal work planning and labour cost control procedures, and extended the existing preventive maintenance routines. In June, 1961, assisted by management consultants, a more scientific approach to maintenance was instituted. The emphasis was placed on the control of labour. The development and application of the primary control system was established with-in six months. Since then, the Department has operated for a year, consolidating the system. The procedure of the installation, the results achieved and the results to be expected will be discussed. JNTRODUCTION THE Milliken Division of Rio Algom Mines Limited operates a 3,000-ton-per-day uranium mine, in the Elliot Lake district of Ontario, which went into production in April of 1958. The lowest operating level is 3,000 feet below surface. Mining is carried out by open stopping, with planned pillar support and footwall haulage on rail.

Jan 1, 1963

By S. Addie

In the early 1990’s the British Columbia (Canada) mineral industry frequently discussed the need to participate in, and compromise with, public environmental interests in order to ascertain long-term stability. However, as the decade progressed the mineral industry withdrew from almost all meaningful public participation. As government protected areas policy in the past year has illuminated, there is a continued need for long-term land access stability. This paper historically analyses the public engagement policies of the British Columbian mineral industry while it participated in long-term consensus-based multi-stakeholder land-use planning processes. From this analysis the paper recommends that the mineral industry reengage the public and institute a new working relationship with environmental advocacy groups so as to ensure British Columbia becomes the most sustainable mineral producing jurisdiction in the world.

Jan 1, 2011

By Bryan Ore, Angel Mateo, Edwin Asencios

La operación de Minera Colquisiri S.A. está ubicado en la provincia de Huaral, inicia sus operaciones en el año 1985. Su sostenibilidad se basa en su sistema integrado de gestión (SIG) y una armoniosa convivencia con la agricultura. Es un yacimiento del tipo sulfuros masivos volcanogénicos (SMV), donde predomina cuerpos de mineral lenticulares, predomina el tipo de roca IIIB, a IIIA. Actualmente viene explotando el cuerpo Sofía D como principal cuerpo mineralizado, con una producción diaria de 1600MT, la cual es procesada en la planta concentradora de minerales polimetálicos. Cuenta con un depósito de Relaves operación y recircula el agua del proceso de sus operaciones en su totalidad.

Sep 30, 2022