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The objective of a mine planning exercise is to plan a safe mine that maximises net present value (NPV) for the project. Two primary elements are key to design of a mine plan optimised to maximise profit: selection of an optimised production rate and selection of an optimised equipment fleet. Both depend upon accurate estimations of capital and operating costs for the equipment and for the life cycle of the mining operation. Once a trial production rate is determined, a primary equipment fleet, ie excavators, haulers, and blasthole drills, can be determined based on material characteristics and haulage distances and gradients. An auxiliary fleet, dozers, road maintainers, service trucks, etc can be determined using less rigid productivity criteria. With an equipment fleet determined, operating and support personnel can be assigned based on shift requirements and equipment operating needs; and material and supply requirements can be estimated. Knowing the areal dimensions of the major equipment items, road widths and repair shop dimensions can be determined. Personnel numbers and supply requirements determine the square metre sizes of offices, change rooms, and storage facilities. Reliable sources of capital and operating unit prices and costs for all these items are referenced in the paper. Once preliminary capital and operating cost estimates are calculated by applying unit costs to equipment, personnel, material and supply needs, potential profit can be tested using DCF techniques. An optimised mine plan can then be determined by testing the potential profitability of multiple mine production rates. Because of the economies of scale, full capital and operating cost estimates must be completed for each production rate in order to produce meaningful comparisons.

Dec 6, 2010

By Jasper L. Stuckey

PYROPHYLLITE, first identified as soapstone,' later as agalmatolite,2 and finally as pyrophyl-lite, has been known to occur in North Carolina for more than 130 years and has been produced intermittently in commercial amounts for the past 100 years. Pyrophyllite mining, however, has become a major industry in North Carolina only during the past 25 years. North Carolina and California are the chief producing states. Current annual production averages 125,000 tons, of which slightly more than 90 pct comes from North Carolina. Distribution and Geologic Setting: All known pyrophyllite deposits in North Carolina are associated with rocks of the Carolina Slate Belt,' which is composed of a vast series of metamorphosed volcanic and sedimentary materials, occurring as two zones extending in a northeast-southwest direction across the state. The larger of these zones, lying in the central Piedmont region, varies from 8 to 50 miles wide. The smaller zone lies along the eastern edge of the Piedmont region and is partly covered by coastal plain sediments. The rocks in both zones consist of a great volcanic-sedimentary series, composed of air-laid and water-laid tuffs and breccias, lava flows, and slates. On the basis of composition, they may be classed into three groups: 1) tuffs, breccias, and lava flows of acid or rhyolitic composition; 2) tuffs, breccias, and lava flows of a basic or andesitic composition; and 3) water-laid slates composed of fine grained materials derived chiefly from the acid tuffs and breccias and

Jan 1, 1959

Mineral exploration and mining in New Zealand has had almost five years of new legislation. The requirement for different consents is a challenging, time consuming, expensive exercise but in most cases the new procedure is working, although the matter of obtaining access to land is still a major issue. Priority is critical. After lodgment of an application for a minerals permit there are many other matters to address such as identifying land owners, occupiers and administrators, preparation of access applications, consultation and preparation of various resource consent applications.

Jan 1, 1996

By Larry Stearns, Lori Tiefenthaler

Remediation of contaminated soil represents a significant market for application of Deep Soil Mixing (DSM). Eighty-one percent of U.S. Environmental Protection Agency (EPA) Superfund Program’s site remedies have involved contaminated soil. Contaminated soil is frequently treated by In-situ Solidification/Stabilization (ISS). ISS treatment of contaminated soil involves mixing binding agents into soil using DSM techniques. DSM is a core business for many DFI members. Members may improve and broaden their services to clients by learning about the recent ISS treatment of contaminated soil at a Superfund site. ISS treatment is part of the EPA-selected remedy for a Superfund Site in the metro New York City area. The property has seen heavy industrial use for more than a century. Soil at the site is contaminated with a variety of volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs) including coal tars and heavy metals, principally arsenic and lead. Beginning in 2017 and continuing through 2018, approximately 150,000 cubic yards (115,000 cubic meters) of soil will be treated by ISS at the case study site. Portland cement and slag cement are mixed into the soil by DSM techniques using GPS guided excavators to immobilize the hazardous constituents within the treated soil. ISS treatment by DSM will contribute to redevelopment of this valuable property. This paper will describe ISS constructability and performance, case study grout mix design with geotechnical results for strength and permeability, and deep soil mixing techniques. INTRODUCTION In-situ solidification and stabilization (ISS) is a deep soil mixing (DSM) technique applied in the environmental remediation field to physically encapsulate, or chemically bind, contaminates of concern such that the impacts to human health and the environment are mitigated. Common remediation applications of ISS include mixing cementitious reagents into contaminated soils to form a monolithic mass with desired performance characteristics, and the installation of vertical subsurface walls designed to control groundwater movement. A key characteristic of ISS is that the contaminated soils are treated in their existing location at the project site and then are left in place after treatment. Typical performance characteristics of the ISS treated soils include improved unconfined compressive strength (UCS), reduced hydraulic conductivity (HC), and reduced leaching potential of soil contaminants. Increased shear resistance of the treated soil may also be a performance requirement where seismic loading is a concern.

Jan 1, 2018

By G de Jong, W Sunyoto, K Sari, P Silalahi

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Big Gossan mine is operated by PT Freeport Indonesia and is one of the largest stope-and-fill mining systems in the world. The Big Gossan deposit is a ~200 m wide, 1200 m long and 500 m high steeply north-east-dipping to subvertical skarn body at the Cretaceous-Tertiary Ekmai-Waripi contact. The copper-gold mineralisation, with a 1.3 per cent copper equivalent cut-off grade, occurs mainly proximal to the Ekmai-Waripi contact in the garnet-clinopyroxene prograde skarn at the base of the Tertiary Waripi formation and partly distal to the contact in the tremolite-actinolite retrograde skarn of the Tertiary Waripi formation.The Big Gossan stope mine is designed from 2540 m to 3020 m above sea level. Present active stoping operations occur at level 2540 mL to level 2640 mL and are done in a primary and secondary stoping sequence. The width and length of the stopes is 15 m and 20 m respectively, while the height of the stope varies between 20 m and 40 m, depending on the ground conditions. The stability of the stopes is visualised in the Mathew’s Stope Stability graphs. These graphs and actual Cavity Measurement Scanner measurements on the stope will predict and show the overbreak and underbreak, which affect the reconciliation of the mined stope and also the pillar stability between the primary stopes. Geological factors like major structures, joints, veins and alteration intensity are important factors that correlated with the stability of the Big Gossan stopes.CITATION:Sari, K, de Jong, G, Silalahi, P and Sunyoto, W, 2015. Stope stability at the Big Gossan skarn deposit, Papua, Indonesia, in Proceedings PACRIM 2015 Congress, pp 139–146 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

The 21st Annual American Mining Hall of Fame Awards Banquet sponsored by the Mining Foundation of the Southwest will be held at the Sheraton Tucson Hotel in Tucson, AZ on Saturday, Dec. 6, 2003. This year’s inductee, guest of honor and featured speaker at the banquet will be Thomas J. O’Neil, recently retired president and chief operating officer of Cleveland Cliffs Mining. Prior to Cliffs, O’Neil spent 10 years with Cyprus Minerals. He was also professor and head of the Department of Mining and Geological Engineering at the University of Arizona. As representatives of mining heritage, the Hall of Fame will induct James Boyd and Thomas F. Walsh. Walsh discovered a rich gold telluride vein in Ouray, CO, which became the Camp Bird gold mine. Boyd was a former director of the U.S. Bureau of Mines, vice president of Kennecott Copper and later president of Copper Range.

Jan 1, 2003

By Christophe Bragard

The Los Angeles Metro Eastside Extension light rail project included a 1.5 mile underground segment, which consisted of twin 18'?10" ID tunnels, bored with two EPB-TBMs. One of the major project challenges after the completion of the bored tunnels was the excavation of six cross passages within alluvial geology below the water table and with low ground cover. Sequential excavation methods were employed and this paper details the design, ground treatment, support measures, and construction methods used to mine these cross passages beneath the congested urban streets of the City of Los Angeles.

Jan 1, 2008

By B. J. Breen, C. S. Mogg

Considerable borehole investigation work has been completed at a proposed site at Sellafield in Cumbria, supplemented by seismic surveys, other geophysical sensing and geological mapping. The focussing of investigation on the rock mass itself will be achieved by means of the planned underground rock characterisation facility, giving access to depths of about 800 m in the strong, low-permeability basement rocks of the Borrowdale Volcanic Group. Characterisation work undertaken during the sinking phase and interaction with continuing surface-based exploration and monitoring should permit a firmer assessment of the long-term safety of a repository. Key considerations in the choice of a design for the repository include the waste handling method, underground inlet cell, underground vaults, vault environment and environmental effects

Aug 1, 1994

By Stephen D. Smith

This chapter summarizes data on crude nonfuel mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rim. Also included are tables that show the principal nonfuel mineral commodities exported from and imported into the United States and that compare world and U.S. mineral production. The detailed data from which these tables were derived are contained in the individual commodity chapters of Volume I and in the State chapters of Volume II of this edition of the Minerals Yearbook. Although crude mineral production may be measured at any of several stages of extraction and processing, the stage of measurement used in this chapter is what is normally termed "mine output." It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the output from auxiliary processing at or near the mines.

Jan 1, 1988

There is a lack of information concerning the movements of water on the continental shelf, particularly with regard to data obtained regularly over significant periods of time. The Horace Lamb Centre for Oceanographic Research has recently deployed data acquisition systems on the sea bed off the coast of South Australia to record tides, swell, and ocean temperatures. Some of these early records are described. The swell data are pertinent to future offshore operations with drilling rigs, barges, and other equipment, while the temperature variations give evidence of significant bottom currents, apart from those due to swell.

Jan 1, 1971

By C A. Locke, M Stevens, P Vidanovich, J Cassidy, J L. Mauk

The Karangahake adularia-sericite epithermal gold-silver deposit, located at the southern end of the Waitekauri Corridor, Hauraki Goldfield, occurs as quartz veins with associated alteration haloes. Integrated geophysical studies were undertaken to determine the expression, location, and extent of these alteration zones. Aeromagnetic data show an extensive, magnetic æquietÆ zone over Karangahake and the southern Rahu Ridge that represents a zone of magnetite destruction resulting from hydrothermal alteration. Analytic signal data are used to define the boundary of this zone; the resulting 6 km2 area is elongate north-south with an irregular boundary. A detailed gravity survey over the area reveals a positive residual gravity anomaly, up to 30 gu in amplitude, over the Karangahake deposit. Density measurements on near-surface rocks give low values indicating that the source of this positive gravity anomaly must be deep; possible causative bodies include an igneous intrusion or dense sulfide mineralisation. To the west and east of the host Waipupu Formation, strong gravity gradients of 100 gu/km and 65 gu/km reflect the faulted boundary of the Hauraki Rift, and the edge of the Waihi Basin respectively. High resolution airborne radiometric data define a 2.2 km2 area of potassium enrichment. This area is elongate north-south and has an irregular boundary. It coincides approximately with the centre of the magnetic quiet zone and the peak of the gravity high, and correlates with known areas of intense mineralisation. Anomalously high potassium counts and elevated K/Th ratios correlate with areas of potassic alteration that have undergone K-metasomatism. Underexplored portions of this zone may indicate areas of gold-silver prospectivity. Combined geophysical data therefore reveal the extent of hydrothermal alteration, and the central zone of Kmetasomatism that is most likely to contain orebodies.

Jan 1, 2005

By A Webster, T Murphy

Block cave mining, in its broadest sense, has transitioned from an orebody/rock mass determined method of extraction, to a low-cost and high production mining method that may be applied to any large ore deposit. This inherently means that caving is now required in more complex rock mass conditions where assistive damage, through preconditioning, may be necessary. This requires comprehensive understanding of the geology, and its interwoven relationship with geotechnical parameters, and is made more challenging due to limited exposure in block cave mines. Limited mine development throughout the cave volume equates to a heavy reliance on drilling data in terms of observations, modelling of the mine geology, and collection of geotechnical data. This translates as increased uncertainty of geological and geotechnical models and has potential to impact significantly on the ability to make informed decisions in the design and operation of the cave mine.Modelling of cave propagation behaviour requires a complex, coupled system of draw of material, flow of material through the cave stocks, and propagation of the cave-back assisted by autogenic stress-related breakage of the rock mass, manifested as seismicity. The role of geological features in the process of cave propagation is not well understood and requires evaluation on a mine-specific basis, given the diversity of geological controls/settings of ore deposits and local variability of stress fields.Seismic monitoring systems can elucidate key geological features and domains, as heterogeneous seismogenic activity is observed ahead of the advancing cave-back. The observations made from analysis of seismic monitoring data may have potential to be used as a validation tool for numerical modelling of predicted cave behaviour in similar geological settings (eg next lift/panel).Understanding of the geological structure, at all scales, is critical to optimise the design and operating decisions made in a block cave operation. At present, intermediate-scale structure, anisotropy, mineralogy and model uncertainty may be neglected or under-represented despite their likely significant role in the mechanisms of cave propagation.Insights from an analysis of the Ridgeway Deeps block cave mine are discussed in this paper.CITATION:Murphy, T, Webster, A and Chitombo, G, 2016. Beyond rock mass characterisation – the impact of geology on block cave mining, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 861–872 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By M P. Simpson

Forty one whole rock samples from the Gold Cross low-sulfidation epithermal Au-Ag deposit have d18O values that range from 4.4 to 9.3 per mil, with an average value of 7.0 per mil. Unaltered and weakly altered rocks have d18O values greater than eight per mil, and the orebody is surrounded by samples that are depleted in 18O. A strongly silicified sample adjacent to the Empire Vein System has a d18O value of 9.0 per mil, similar to previously reported analyses of vein quartz (7.0 to 11.7ë, average 9.4ë). This suggests that, in detail, Golden Cross may have a zone of 18O-enriched wall rocks in the core of the deposit, adjacent to the main underground veins. Although some workers have suggested that stable isotope geochemistry may provide useful information for epithermal mineral deposit exploration, at Golden Cross this is not the case. Alteration minerals, major elements and trace elements all define larger, less ambiguous halos than the zone of 18O-depleted wall rocks.

Jan 1, 2001

By R. R. Sayers

THE South African Mining and Engineering Journal recently pointed out that no satisfactory solution of the question of compensation for silicosis can be arrived at by placing further liability of an inequitable nature upon the mines. There are at present 35 scheduled mines liable to contribute to the annual levy of $800,000 and provide for the net outstanding liability of $6,400,000. Several of these mines have, as yet, not been able to set aside sufficient funds against their out- standing liability to the Compensation Fund. The gold producers declare that the gold mining industry today is passing its zenith, and that the production of gold will decline, with a consequent lessening of the spending power of the mines, which in about ten years will be reduced to a great extent unless encouragement is given for the opening of new mines. It is during this period of decline that the mines will be required to meet the large burden already created by miners' phthisis. In England the Workmen's Compensation Act, 1925, was extended to industries involving exposure to asbestos dust.

Jan 1, 1931

By Dong-kil Lee

Field tests have been conducted to investigate the characteristics of flow and physical chemistry of acid mine drainage(AMD) in the Hwangji-Yuchang settling pond in south Korea. pH and ferrous concentration of AMD flowed in the settling pond is 6.79 and 25.5 mg/l, respectively. As a results, we found that the ferrous oxidation reacted strongly around the inlet of the pond and the distributions of physicochemical properties is depended on flow characteristics and ferrous oxidation rate of AMD.

May 1, 2011

By Jodi Roberts, Curtis Deredin, Jean-Guy Paulin

"Since the establishment of the Six Sigma quality improvement program in 2001, several projects have been successfully carried out in the copper-lead, zinc, copper separation, lead upgrading and bulk flotation circuits in the Brunswick Concentrator.This paper provides an update on the process improvement initiatives that have taken place since 2004 using the Six Sigma methodology:•,The recirculation of warm water to the flotation circuit (to save on energy costs)•,Installation of a heat recovery tower to recuperate the heat lost from the zinc dryers•,Installation of an extra row of cleaner-scavenger cells for the copper-lead circuit for extra capacity, and a new reagent scheme for the copper separation circuit that have increased copper and lead recoveries.INTRODUCTIONThe Brunswick Mine Concentrator (Xstrata Zinc Canada) is located near Bathurst, New Brunswick and is one of the world’s largest lead/zinc mines. Milling of ore commenced in 1964 from the No. 12 orebody, with an expansion in 1966 to accommodate ore from the No. 6 open pit mine. The concentrator utilizes selective flotation to produce zinc, lead, copper, and bulk lead/zinc concentrates. The ore is a complex massive sulphide, consisting of approximately 20% valuable minerals, 60% pyrite and 20% silicates.Figures 1, 2, and 3 illustrate the historical annual average metallurgical performance and process improvements achieved at Brunswick Mine for the zinc, lead and copper concentrate products. The objective is to continuously direct metallurgical performance towards increasing grades and recoveries while minimizing operating costs."

Jan 1, 2008

Vale Inco?s Coleman Mine 153 Orebody is a narrow vein deposit with a dip that varies from 30 to 70 degrees. It has a strike length of 1200-feet and the current mining extends from the 4250 level to 5100 level. The primary mining method is mechanized cut-and-fill although drift-and-fill is also used in wider sections of the ore zone. The ore body is divided into six main mining horizons with an average of three mining blocks on each cut. There are some interesting rock mechanics challenges related to mining upward from the 4550 level and these challenges are increasing as the mining front progresses toward the 4400 level. The mining of the 4550 block is currently at cut 13 whereby the crown pillar thickness is approximately 60-feet. Significant factors including increased stress levels in the crown pillar, the change in the orebody dip at this level and a recently indentified geological structure in the footwall, have all combined to introduce seismic activity in the footwall of 4550 level. Closer studies revealed a consistent trend of seismicity that was further examined with core logging and Acoustic TeleViewer technology. The data from these assessment tools disclosed a geological structure that is influencing the mining environment. This paper reviews the seismic analysis for the 4550 level mining zone and the subsequent procedures used to locate the new geological structure. The paper also discusses the key mining practices used to successfully mine cut 13 of 4550 level and briefly reviews the studies that are underway to up-date the mine design for continued extraction of high-grade ore in a safe and productive manner.

May 1, 2009

In general, the metallurgical industry has so far been slower than the chemical industry to adopt ion exchange materials for industrial processes. The atomic energy industry presents a marked exception to this general situation, and the literature shows a rapidly increasing use of ion exchange techniques for the recovery of atomic energy metals on scales ranging from the ultra micro up to that of the largest mining operations. In many cases, the processes used would be equally applicable to more common metals and it is hoped that this review will be of interest to metallurgists outside the specialised atomic energy field. The review is intended to describe developments of ion exchange processes made during the last three years. Earlier studies have been summarised by Kunin and Preuss (1956) and Roland (1957). In order to restrict the number of references discussed, purely analytical procedures have been omitted and only those processes which have been conducted on a reasonably large scale or which, from their nature, areclearly capable of being upscaled, have been considered. The paper is divided into five main sections concerning respectively:Water treatment and effluent disposal.Metal recovery and purification.New ion exchange materials.New ion exchange equipment.Membrane cells.WATER TREATMENT AND EFFLUENT DISPOSALA high proportion of atomic reactors, and particularly those of American design, are cooled by water which is...

Jan 1, 1961

By L. Boyd, A. Charland, G. Potts, D. Fragomeni, N. O. Lotter

"The Raglan orebody and concentrator has been the subject of study in Process Mineralogy at Falconbridge since 1998. (Lotter and Tuzun, 1998) The orebody is classified into three distinct textural groups, or end members. These are referred to as disseminated, net-textured, and Massive Sulphides, and differ in terms of mineral grain size, nickel grade, hardness, and mineral association. In this paper, it will be shown that the sampling and characterisation of each end member on an individual basis develops a higher-level understanding of the processing requirements and behaviour of the mixture of ore as presented to the mill.The end members have been used in robust prediction of recovery at various grind size p80 from laboratory scale High Confidence Flotation Tests. Weighted mean mixtures of the end members have been mathematically combined to determine impact of textural distribution on metallurgical performance as a function of grind size.The ore end members also vary in hardness and breakage mechanism and have been used to model throughput capability for existing, optimized and retrofit grinding circuits. This modeling has provided a range of expected throughputs as the relative proportions of each end member varies.Finally, the differing grinding requirement per end member has led to the development of grinding and flotation strategy that increases rougher flotation recovery and provides flowsheet options for a concentrator expansion. This leads to further understanding of the plant performance as a function of ore mixture."

Jan 1, 2005

By D. A. Ainsworth

"The first known use of activated carbon dates back to the Ancient Egyptians who utilized its adsorbent properties for purifying oils and medicinal purposes. Centuries later, the early ocean going vessels stored drinking water in wooden barrels, the inside of which had been charred. (However, by modern definition the carbon used in these applications could not truly be described as activated.) By the early 19th century, both wood and bone charcoal was in large scale use for the decolorization and purification of cane sugar.However, it was not until the beginning of the First World War that the potential of activated carbon was really capitalized upon. The advent of gas warfare necessitated the development of suitable respiratory devices for personnel protection. Granular activated carbon was used to this end as, indeed, it still is today.By the late 1930's there was considerable industrial scale use of carbon for both gaseous and liquid phase application and new manufacturing processes had been developed to satisfy the needs of industry. During the 1939-1945 war, a further significant development took place - the production of more sophisticated chemically impregnated carbon for the removal of both war and nerve gases."

Jan 1, 1984