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By Gary J. Fletcher

Mining and processing activities which are proposed on private land, state leases, or unpatented mining claims are governed by numerous local, state, and federal laws which identify the procedures and conditions which must be met before resources can be developed. The respective government agencies responsible for the administration and enforcement of these laws have promulgated supporting regulations and guidelines, and have implemented certain permit and approval processes to ensure compliance. Each exploration project has a unique environ- mental setting and location which further dictates the types of air, water, hazardous waste, and wildlife laws and regulations which must be complied with before development commences. The environmental planning process should be the first step in the evaluation of existing company properties and the potential acquisition of other mineral properties. However. many company don't consider the environmental requirements for a project until the decision is made to develop the property for mining and processing. If a mining company wants to expedite the environmental planning process, it must first develop an in-house process for evaluating the project and determining the environmental approval procedures in the state where the project is located. The first stage of environmental planning involves general information which can set the overall company philosophy for development of projects.

Jan 1, 1987

By Paul C. McWilliams

The U.S. Bureau of Mines has, primarily through its contract program, used large-scale centrifuges to determine design criteria for tailing embankments. The centrifuge runs were made at two installations, the University of Cambridge, Cambridge, England and Sandia National Laboratories, Albuquerque, NM. The major problems considered were as follows: slope stability of embankments, modeling erosion and seepage, use of the phreatic surface level to ascertain the validity of centrifuge modeling, and the effects of compaction and weathering on a tailings embankment. This report summarizes the results of the four test series conducted at University of Cambridge and Sandia National Laboratories. A review of prior centrifuge applications to mining problems is included. Consideration is given to future centrifuge application to mining problems in both soil and rock mechanics.

Jan 1, 1989

Delivered at the University of Sydney, on June 4th, 1954.THE TORCH WE HOLDLast year Our Institute celebrated its Diamond Jubilee, coincident with the holding of the Fifth Empire Mining and Metallurigcal Congress in Australia and New Zealand. We can be proud of our growth over the 61 years since the inaugural meeting in Adelaide in April, 1893, which followed suggestions from a provisional committee of mining men, formed in 1892 in Broken Hill.We can also be proud of our technical achievements in the fields of economic geology, mining and metallurgy.Should we be content with the growth of our mining and metallurgical industries over these years? My answer is in the negative. The discovery of new mineral deposits is essential for the continuance and development of the industries we represent.Let me review the background and trends of our industry in an attempt to emphasise the changing factors influencing the search for minerals and their exploitation.Australia was blessed with the discovery of coal in New South Wales in 1796; copper in South Australia at Kapunda, Burra, Wallaroo and Moonta in the eighteen-forties; gold in Victoria and Eastern Australia in the 'fifties; tin at Mount Bischoff, Tasmania, and gold at Charters Towers, Queensland, in the 'seventies; lead-silver at Broken Hill, New South Wales; gold and copper at Mount Morgan, Queensland, and copper at Mount Lyell, Tasmania, in the 'eighties; and gold at Kalgoorlie, Western Australia, and zinc-lead atRosebery, Tasmania, in the 'nineties. As well, the iron ore deposits of the Middleback Ranges, South Australia, and Yampi Sound, Western Australia, were known before...

Jan 1, 1954

By M. Bunch

"THE SUPER CYCLE IS GONE The utopia of the rising sales volume, for mining companies from 2002-2011, was entirely due to rising production volume and prices. The Australian mining sector experienced an 18 percent annual growth rate in revenues, and 11 percent growth in prices. (1) However, EBIT remained flat during the same time period. In addition, Australian mines saw a 7 percent annual decline in both labor and capital productivity. (2) Mines in the U.S. and Canada produced similar results, whereas the world-wide mining industry has seen a productivity drop of 40% since 2001. (3) The decade “Bull Run” of rising prices was trashed by companies that chased low-quality assets while increasing debt on their balance sheet. It seemed everyone believed the “super cycle” would last forever, while completely ignoring the history of cycle downturns. Worldwide mining operations are as much as 28 percent less productive today than a decade ago, according to new McKinsey research. The results from McKinsey’s new MineLens Productivity Index (MPI), which adjusts for declining ore grades and mine cost inflation, show that the pronounced decline in productivity is evident across different commodities and is seen in most mining players and geographies. (4) McKinsey sees three important areas of focus to address the root causes of productivity decline. 1) Embed effective management operating systems at mines 2) Prioritized operational excellence and capabilities development 3) Focus on innovation Reality has now settled back in and companies are struggling to make ends meet. The basic management staple of controlling costs and improving the production/productivity that was lost in the excitement is now back in play. Traditional cost-cutting approaches, such as across-the-board spending cuts, layoffs, and hiring freezes are only short-term initiatives and will not permanently improve a company’s cost structure or improve long- term competitiveness. This can only be accomplished by engaging front-line employees and empowering them to make necessary improvements in their daily work. It is time for leaders to lead and develop cultures of continuous improvement within their organizations in order to sustain their mining project to the end of mine life. Successful operating managers require two different skill sets of Leadership and Management; knowing how to lead people in their organization and how to manage the work they do."

Jan 1, 2016

By Kenneth H. Johnston

Records show that waterflooding was tried in Osage County as early as 1934, but it was not economically important until a large unitized flood in the North Burbank field was begun in 1950. Development was rapid and by the end of 1960, there were 70 active water flood projects and 16 active pressure-maintenance projects in the County. The locations and status of the water-flood and pressure-maintenance projects in Osage County on December 31, 1960 are shown in figure 1, and information pertaining to these projects as of July 1, 1960 is given in table 1. For the past several years, Bureau of Mines petroleum engineers have arranged tours of selected waterflooding projects for the spring meeting of the Kansas-Oklahoma Water flood Association. These tours are conducted to demonstrate unique operating methods and new field equipment and to provide additional opportunities for exchanging information. Each of these tours has been supplemented by a published report describing in detail the projects visited. This report has been prepared for distribution during the 1961 spring tour of three waterflooding projects and a pressure-maintenance project in Osage County, Okla. (fig. 2).

Jan 1, 1961

This paper reviews the history of refractory materials, highlights the development of refractory technology over the years, draws attention to the technology behind these materials, and comments on future developments in this field. By walking the path with refractory materials, from their initial uses in BC times, to the composite materials that are used nowadays, and the nanotechnology developments that are currently taking place in this field, the reader will come to agree that refractory materials are indeed very ?cool?! Keywords: refractory materials; bricks; monolithic materials.

Jan 1, 2008

In bump-prone coal mines, roof and rib support is subject to dynamic as well as static loading. Although less frequently encountered, the dynamic loading component can result in violent coal expulsions into openings seriously threatening the safety of workers. Dynamic support systems that have been increasingly implemented in many deep hard rock mines for dynamic failure containment have not yet found their adaptation to deep coal mines at desired levels. This paper examines the potential use of some of these dynamic support systems in deep coal mining, particularly in the western United States. Fundamental principles of dynamic loading are reviewed in the context of their application to dynamic failure mechanisms in coal mines. Potential benefits and applicability of the suitable hard rock dynamic support systems are discussed in relation to coal bump mitigation. The resulting insight provides a starting point for development of dynamic support elements for bump prone conditions in deep coal mines.

Jan 1, 2009

By Detlef Ehlert

With the proven “Plug & Work” concept developed by SMS Siemag, automation systems are tested and optimized in the test field in a near-reality environment before being shipped and commissioned at a customer’s site. The process and production simulations provide scenes showing the specific mechanical equipment, the drive systems and the technology of the corresponding customer plant. Beside the technological simulation of the plant and the IO-simulation with the automation system, the production simulation is one of the three important parts of the Plug & Work simulation environment. It serves two important additional purposes: the 3D visualization of the entire customer plant on the one hand and the mapping of the logistic procedures in the plant on the other. In order to provide a close-to-reality visualization of the plant, the original design data of the individual customer plant are used for creating the visualization and prepared using an appropriate export filter. In this way, it is ensured that production sequences can be optimized in advance together with the customer, so that each customer can be trained on his own future plant.

Aug 16, 2017

By Edgardo Torres Hernández

El Proyecto Optimización de Ángulos de Taludes en Explotación de Minas es un proyecto desarrollados por E-Mining Technology (EMT), socio estratégico de Prodimin en Perú, para Codelco Chile en uno de sus yacimientos del Norte de Chile. El desarrollo de este proyecto estuvo enmarcado en el Programa de Proveedores de Clase Mundial; programa que tiene como misión desarrollar un sector de proveedores intensivo en conocimiento, mediante la generación de soluciones tecnológicas empujadas desde la demanda de la minería y desde la propuesta del sector de proveedores que puedan ser escaladas a otros sectores y mercados.

Sep 1, 2017

By Don Thompson

It isn?t a lie if you don?t tell the whole truth The pictures National Geographic didn?t print Other photos National Geographic didn?t print?

May 1, 2009

By Roger L. Baer

Marine disposal of mill tailings has been practiced worldwide for over a century. However, only recently have the environmental effects of marine disposal been systematically studied. Some early attempts at marine disposal of tailings resulted in adverse impacts to marine life. However, recent advances in tailings disposal methods have included the introduction of engineered submarine tailings discharge systems, advanced environmental assessment and monitoring methods, and oceanographic modeling systems. Successful submarine tailings disposal (STD) has occurred at several mines. The U.S. Bureau of Mines (BOM) has undertaken studies of the disposal of mining and milling wastes in the marine environment. The BOM Alaska Field Operations Center, Juneau, initiated a review of the technology, regulations, and economic aspects of STD. The review illuminated the need for organization of literature on the subject, therefore the Bureau compiled this extensive bibliography on marine disposal of mill tailings. The bibliography presented here contains 1483 references and is also available through diskette in the Word Perfects format. A review of the references indicates that literature on submarine disposal inadequately covers the subject. The majority of the references listed only peripherally relate to the subject. Published literature on the engineering and environmental aspects of STD is severely limited.

Jan 1, 2011

By J. W. Givens, P. B. Crawford

A potentiometric model study has been made of the effect of vertical fractures existing in the matrix of the reservoir on the flooding or cycling performance. Fractures can have unusual flow characteristics. Fluid entering one side of a fracture can emerge on either the same or opposite side of the fracture, depending on the particular streamline. Fracture orientation has a great influence on the sweep efficiency. However, sustained fluid injection may still permit large areas to be swept. INTRODUCTION One can find considerable information available in the literature on the effect of fractures originating at the wellbore on sweep efficiencies of water-flooding or gas cycling programs.1-5 However, there arc few, if any, quantitative data reported in the literature on the effect of vertical or horizontal fractures existing out in the reservoir matrix on secondary recovery performance. Several papers have been presented on the effect of vertical and horizontal fractures on the productivity or conductivity of waterflood and gas injection patterns, but in all cases the fractures initiated at the well and simulated commercial fractures.6,7 It is believed that natural fractures may exist out in the reservoir matrix and would effect the displacement performance. The purpose of this report was to study the effect of a few isolated vertical fractures existing out in the reservoir matrix on the performance of waterflood or gas injection patterns. DESCRIPTION AND EQUIPMENT Since the potentiometric model was described by Lee8 it has been widely used to study numerous types of fluid displacement problems. The potentio- metric model can be used for fluid displacement studies when the following assumptions are valid: (a) steady-state conditions exist; (b) the mobilicy ratio is one; and (c) the capillary and gravitational effects can be neglected. Five-spot and direct line drive square patterns were studied using a copper strip of the desired length and orientation to simulate a vertical fracture in the reservoir matrix. The 20 x 20-in. model was considered to represent only one element of an infinite array of similar patterns. DISCUSSION AND RESULTS FIVE-SPOT PATTERN — ONE FRACTURE BETWEEN INJECTION AND PRODUCING WELLS Fig. 1 shows a quadrant of a five-spot pattem with the vertical fracture existing out in the matrix along a line connecting the injection and producing wells. Length of the fracture was equal to 35.4 per cent of the distance between injection and producing wells. In this particular pattern it is noted that fluid breaks through from the injection well to the producing well when the dimensionless time is equivalent to 26.9. Dimensionless time is defined as volume of fluid injected divided by the volume of displaceable fluid in the pattem expressed as a per cent. The cross-hatched areas of this

Jan 1, 1967

The Zeehan field has yielded over 190 000 tons of lead and 26,000,000 oz of silver. Moh of the production took place between the initial discovery of silver-lead ore in 1882 and 1920, and the greatest part was extracted from fissure lodes in the Proterozoic to (?) lower Cambrian rocks. It is demonstrated that the prosperity of the mines relied upon the silver content, which is apparently highest in these beds, particularly where spilitic rocks are associated with them. In contrast, galena occurring in orebodies emplaced in the Gordon Limestone is low in silver.Most of the workings are relatively shallow due in some cases to enrichment related to erosion surfaces.Fault zones within a complex anticlinal structure exposing the Proterozoic to (?) lower Cambrian formations appear to have been major factors in the control of mineralization.

Jan 1, 1968

By S. M. Javad Koleini

Processing of phosphate ore sample was investigated for increasing phosphate content and reduction of its gangue minerals such as carbonates and silicates. Experimental designs were per-formed using Taguchi method. Different flotation methods were investigated for Moundon phosphate ore sample and three methods were used as follow: direct cellophane flotation, reverse calcite flotation and reverse quartz flotation. Because of the sensitivity of cellophane flotation to slime content, prior desliming was carried out before the experiments. Direct flotation experiments carried out and a concentrate contained 23.80% P2O5, 6.88% SiO2 and 72.33% recovery were produced. The achieved P2O5 content in the produced concentrate from reverse flotation of calcite was 26.44% and the recovery was 82.56%. The concentrate products obtained at optimum conditions by direct flotation of phosphate and indirect flotation of calcite were subjected to indirect flotation of calcite and direct flotation of appetite and final concentrates with P2O5 grade of the order of 24.19% and 26.96% were obtained, respectively. It was concluded that one stage direct flotation is unavoidable to achieve a product with low SiO2 content.

Jan 1, 2014

This sheet explains your audiogram (hearing test) and gives some basic information about protecting your hearing. Keep it so you can refer to it later. What is an audiogram? • An audiogram is often called a “hearing test,” but there’s no pass or fail • It is a written record of your hearing levels • A series of audiograms can track changes in hearing over time • Your hearing threshold levels (the quietest sounds you can hear) are measured in decibels (dB) at different frequencies from low (500 Hz) to high (8000 Hz) Why should I get audiograms? • To measure your hearing ability • To identify hearing problems • To monitor success at maintaining your hearing • To see if noise exposure is affecting your hearing Do I have normal hearing? Compare your hearing threshold levels to this scale: -10 – 25dB Normal hearing 26 – 40 dB Mild loss 41 – 55 dB Moderate loss 56 – 70 dB Moderate/severe loss 71 – 90 dB Severe loss 91 – 100dB Profound loss [ ]

Jan 1, 2008

By L. G. Marshall

This report describes dredging and processing of sand and gravel from a glacial-fluvial deposit in the Raccoon River valley near West Des Moines, Iowa. Preliminary cleaning and separation of the sand and gravel at the dredge site with subsequent transportation to separate plants and the production and disposal of the various grades of aggregate material are also described. The geology of the deposit is summarized. A tabulated summary of costs in units of labor, power, and supplies is included.

Jan 1, 1963

By Healy T. W, Dixon D. R

The present study 'of pure ZnS and NiS and ZnS (marmatite) by detailed electrokinetic methods has shown that by careful control of experimental parameters much new' information on sulphide-water interfaces can be obtained. Time-dependent processes of alteration of sulphide surfaces are foHowed by electrokinetic methods and indicate that the isoelectric point of the surface depends on elemental sulphur coverage, oxidation product coverage, and the conditions which promote or minimize such reaotions in the presence and absence of activator.

Jan 1, 1977

By Henk van der Bijl, Sean Rogers, Eugene Sidorski, Alan Carpenter

The electrode column is the heart of the submerged arc furnace. Superior electrode performance provides improved furnace performance. This paper describes the main features of the electrode column that delivers superior performance in furnaces worldwide, developed by Pyromet. Pyromet?s electrode comprises the compact slipping device, lower electrode assembly, upper and lower mantles, self-adjusting electrode seal, paste heaters, and Pyromet?s patented innovative electrode breakage detection and length determination system. Pyromet?s slipping device features compact interlocking clamping rings, incorporating fail-safe spring-loaded design. The interlocked clamping rings distribute the clamping force over a larger area of the electrode casing, preventing damage. The slipping device assembly features a low maintenance modular design that allows rapid slipping cycle times, back slipping, and compatibility with Pyromet?s electrode breakage detection and length determination system. Pyromet?s lower electrode assembly consists of the contact shoes, pressure bellows, pressure ring and heat shields. The contact shoes and pressure ring are designed for long, trouble free operation whilst the pressure bellow configuration equalise contact pressure and current distribution. Furthermore, the contact shoes incorporate a self cleaning feature, ensuring optimum electrical contact. The segmented design offers easy maintenance. Pyromet?s clients experience less down time due to longer component life. Pyromet?s remote adjusted electrode seal assembly reduces the rope seal working temperature, increasing rope life. The self compensating rope seal clamping force ensures an effective seal as the rope wears. Pyromet?s electrode breakage detection and length determination system detects electrode breaks utilising Pyromet?s electrode holder and data processing system. The length measurement system controls electrode length, eliminating the occurrence of short electrodes. The length measurement system furthermore eliminates the need for manual electrode length measurement, reducing associated production losses during furnace burn downs.

Jan 1, 2007

Development of a permanent human base on the Moon for exploration requires a self sustaining system. This entails production and processing of limited amounts of raw material on the Moon. Any mining and construction activities on the Moon can only be performed by a robust excavation machine that can excavate a variety of material from loose surface regolith to consolidated (frozen) regolith with embedded rocks in the mixture. Meanwhile, limited amount of information on lunar regolith is available to develop and optimize a machine for given lunar ground conditions. Therefore, any excavator designed for use on the lunar surface should have the ability to adapt to a wide range of operating conditions. A prototype cutterhead for the lunar excavator was built and tested at the Kennametal facility in Latrobe PA A. This paper discusses the results of initial material characterization as well as full scale tests of a prototype cutterhead inrelevent material. A brief review of anticipated production rates under various assumed ground conditions will also be presented.

Jan 1, 2009

By J. Gómez-Hernández, P. K. Kaiser

Abstract The process of stress-induced fracturing around underground excavations in brittle rock is associated with dilation or volume increase of the failed, fractured rock. Different attempts to account analytically for this dilation have been made within the framework of plasticity theory. This theory has been developed mostly for metals, strain-hardening materials or soils, but brittle failure of rock-like materials is characterized by strain-softening behaviour and the volume change is dominated by geometric factors, which may violate stability principles of plasticity. In this work a semi-empirical Rock Mass Bulking Model (RMBM) was developed, using as starting concepts: dilation angle, plastic strain rates, effective deformation modulus, effective Poisson's ratio, Griffith locus, and the definition of a bulking factor BF introduced by Kaiser et al. (1996). The model was calibrated in order to obtain bulking factors that are consistent with experimental data and case studies of measured bulking around underground excavations. Résumé La fracturation provoquée par le stress autour des excavations souterraines dans le minéral friable est associée à la dilatation ou à l’augmentation du volume de la roche en rupture. Dans le cadre de la théorie de la plasticité, différents essais ont été faits dans le but de trouver une justification analytique pour cette dilatation. Cette théorie a d’abord été élaborée pour les métaux, les matériaux ou les sols d’écrouissage, mais la rupture fragile de matériaux d’aspect rocheux est caractérisée par un comportement d’amollissement et le changement de volume est dominé par des facteurs géométriques, ce qui pourrait ne pas être conforme aux principes de stabilité de la plasticité. Dans le présent ouvrage, un Modèle semi-empirique de masse rocheuse a été élaboré, dont les concepts initiaux sont les suivants : angle de dilatation, vitesse de fluage plastique, module effectif de déformation, coefficient effectif de Poisson, locus de Griffith, et la définition d’un facteur de foisonnement FF apportée par Kaiser et al. (1996). Le modèle a été calibré afin d’obtenir des facteurs de foisonnement qui soient conformes aux données expérimentales et aux études de cas sur le foisonnement mesuré autour des excavations souterraines. Kurzfassung Der Prozess von Brüchen in unterirdischen Abgrabungen in sprödem Gestein ist mit der Ausweitung oder der Volumenzunahme des gebrochenen Gesteins verbunden. Verschiedene Versuche im Rahmen der Verformbarkeitstheorie haben versucht, diese Ausweitung analytisch festzustellen. Die Verformbarkeitstheorie wurde hauptsächlich für Metalle, kalthärtende Werkstoffe oder Böden entwickelt, da sprödes Versagen von Gestein ähnlichen Werkstoffen von kaltenhärtendem Materialverhalten gekennzeichtnet ist, und die Volumenveränderung von geometrischen Faktoren beherrscht wird, die die Stabilitätsprinzipien der Plastizität übertreten. In dieser Arbeit wurde ein halbempirisches Rock Mass Bulking Model (RMBM) (Modell für das Aufgehen der Gesteinsmasse), entwickelt, für das die folgenden Anfangsprinzipien benutzt wurden: Ausweitungswinkel, plastische Fliessensätze, wirksames Verformungsmodul, leistungsfähiges Poissons Verhältnis, die Griffith Ortskurve und die Bestimmung eines Aufgehensfaktor BF1 der von Kaiser et al. (1996) eingefürt wurde. Das Modell wurde so kalibriert, dass es die Aufgehenfaktoren erzielte, die mit den Vesuchsangaben und den Fallstudien von Aufgehensmessungen in unterirdischen Abgrabungen übereinstimmen.

Jan 1, 2003