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By Reed. Donald F.

"Deposits of gray hematite occur in two districts in Talladega County, Ala., the Emauhee-Tallasochatchee and Weewoka, both in the vicinity of Winterboro, 50 miles east of Birmingham.The deposits were investigated by the Bureau of Mines in 1943 and 1944. Approximately 13,000 feet of diamond drilling was done and 6,000 linear feet of trenches excavated and sampled.A total of 13,000,000 tons of ore averaging 36 percent iron was indicated in all areas.A detailed discussion of each property investigated, drill logs, and sampling results are given in this report.In the work done in the Talladega County iron investigation, special acknowledgement is due to Paul M. Tyler, formerly regional engineer, Eastern Region, and Richard W. Smith, formerly district engineer, for aid and direction of the project; also to J. B. Clemmor, metallurgist, for diligent research work in the Southern Experiment station laboratory. All were members of the Bureau of Mines Staff.The project was conducted in cooperation with the Federal Geological Survey, whose field work was in charge of T.G. Andrews assisted by Brewster Baldwin. The able and valuable assistance of Andrews and Baldwin aided greatly in accomplishing the project.The areas investigated by the Bureau of Mines were in two districts: The Emauhee-Tallaseehatchee district, between Sylacauga and Sycamoer (marked B on fig. 1) and the Weeworka district, between Winterboro and Sycamore (marked A on fig. 1)."

Mar 1, 1949

It is a pleasure to submit to the National Critical Materials Council (Council) some of my thoughts concerning the important tasks which lie before you. It long has been my belief that America's economic health and national security may depend to a substantial degree on whether we have available to us an adequate supply of critical and strategic materials at reasonable cost. To the extent the Council can contribute to the identification and implementation of wise public policies which facilitate the achievement of that goal, we and our children should be grateful. Even before assuming office, President Reagan warned of the danger of undue dependence on imported materials essential to the Nation's defense and economic well-being. After his election, he appointed a transition task force on strategic and critical materials, and he later directed the Cabinet Council on Natural Resources and Environment to prepare .a National Materials and Minerals Program Plan and Report to Congress, which he forwarded to the Congress in April 1982. In 1984, my predecessor, Secretary Clark, established the National Strategic Materials and Minerals Program Advisory Committee, popularly known as the "Mott Committee" because of its distinguished chairman, retired Admiral William C. Mott.

Jan 1, 1986

By P Clark, P A. Kirsch, R Tapia Rivera

Community members’ sources of information about companies’ social investments are often influenced by the messages in a variety of communication channels, such as newspapers, television and social media. In this sea of communication channels, corporate communications may not always have the desired effect in influencing community perceptions. This paper explores the efficacy of communication between mining companies and communities in Chile through content analysis of corporate sustainability reports and newspaper reporting.Chilean media reporting between 2005 and 2013 is examined to identify community perceptions of corporate social investments made by mining companies. Content within the Chilean newspapers El Mercurio (national) and Soy Chile (regional) is contrasted with content from corporate sustainability reports published by The National Copper Corporation of Chile (Codelco) and Barrick Gold Corporation, Canada (Barrick) for the same period. The objective is to identify differences in the way that corporate social investments are reported by companies in sustainable development reporting and by media in newspapers.Overall, the study demonstrates that the media’s framing and reporting of corporate activities was more negative than positive. Moreover, media outlets tended to focus upon the ‘negative impacts’ or ‘damage’ to communities brought about by mining developments. Conversely, companies’ public communications were largely focused upon direct improvements in livelihoods (health, education, etc) of neighbouring communities. This preliminary study provides a baseline for the development of new formats of effective communication with neighbouring communities. The paper advocates for an increase in participatory mechanisms with affected parties, which could lead towards a greater mutual understanding of the impacts and draw parties closer together.CITATION:Tapia Rivera, R, Kirsch, P A and Clark, P, 2014. Challenging Perceptions? Sustainability Reporting, the Media and Mining, in Proceedings Life-of-Mine 2014 , pp 413–426 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By Donald W. Ross

"INTRODUCTION Sponge iron has been made commercially since 1912 at a Swedish ceramic plant; and the product, known as Swedish disk—type sagger sponge iron, has an excellent reputation as a superior furnace feed wherever high—grade steels are made. The general procedure for making brickyard sponge iron was described frequently in Swedish technical journals prior to 1932 and at that time consisted in filling clay refractory containers, called saggers, with a super-concentrate of Gellivare magnetite plus the necessary amount of solid reducing agent and desulfurizer and then firing in a Hoffmann ring furnace, as used in the ceramic industry.The early Swedish publications describe two types of brickyard sponge iron: (1) An inferior high-sulfur product obtained by mixing the ore and reducing agent, and (2) a high-grade low-sulfur product in the form of coherent disks 7 to 9 inches in diameter and 1 to 1-1/2 inches thick made by the saggers with alternate layers of solid-fuel reducr and of uniaxed ore."

Sep 1, 1945

By Staff

"INTRODUCTION Sheet mica is one of the most important minerals in modern industry. It is used in many kinds of electrical devices, and up to the present time no satisfactory substitute for it has been developed. It is necessary for the successful operation of airplanes, ships, motor vehicles radios, and radar equipment. Early in World y r II, the Array and Navy, foreseeing the need for conserving the stock of sheet mica on hand and realizing that imports from India and Brazil were falling off, had strategic mica placed on the critical war-materials list.Examination and exploration by the Bureau of nines indicated that there probably are large undeveloped deposits of mica in Alabama, some of which are near the surface and others at greater depth. The quality of most of this mica is high.During World War I, Alabama mica producers added materially to domestic production, but after 1920 virtually all of the mines closed end miners scattered. During World War II, when imports from India, Madagascar,Brazil,,other foreign sources were reduced, sometime was required for Alabama to act into production. Operators began to produce small quantities in 1942.The Colonial Mica Corporation was created by the Government during 1942 to buy Mica for the Metals Reserve Company, end later Colonial was made sole buying accent for strategic mica. About this time the Bureau of Mines estab¬lished the graphite field laboratory at Ashland, Ala. Samples of mica wore submitted for examination, and advice was requested by property owners and mine operators. This continued during 1943, when as many as 400 visitors a month called at the Bureau's Ashland field laboratory."

Aug 1, 1946

By William A. Hustrulid

The subject of surface mine development is large. This section covers the fundamental concepts involved in both the open pit mining of thick or steeply dipping deposits as well as the strip mining of thin, shallow, and relatively flat-lying seams or beds. Design involves the marrying of geometries, ore and waste characteristics, equipment, and economics so that the desired result is achieved. Generally, there are many possible combinations from which to choose. For example, extraction over a short time period requires one strategy while quite another is applied for longer times. Variations in supply and demand require some flexibility of operation. Customer requirements impose certain constraints regarding the set of possible designs. Over recent years, planning and operating considerations for surface mining imposed by environmental requirements have increased markedly. There have, at the same time, been enormous advances made in the design aids available to the mine planner. Computer simulation of the various options, whether it be for mine design or equipment selection, provides detailed information for decision making in real time. A significant challenge to the engineer/planner is how to best use the aids avail-able. Because of the widespread use of commercially available and in-house computer software by industry, this section does not deal with the details of planning (for basic coverage of mine development, see Section 7). Rather, some of the basic concepts are stressed. The principles involved in equipment sizing and selection are discussed. A highly important but sometimes over-looked aspect of planning, haul road design, is also covered. For surface mining operations of the future, in-pit crushing and conveying will become even more important. Some of the considerations for application evaluation are included. The section concludes with some future concepts for surface mining.

Jan 1, 2008

Enhancing the Flotability of Gold-Bearing Ores by a Mixture of Collectors

Sep 13, 2010

By Kenneth Wardell

Criteria have been fully developed for determining the optimum size of oil and gas well blocks. The criteria lead to the formation of well barrier pillars which are, of themselves, inherently stable and take account of variable mine roof and floor conditions. The criteria ensure, through considerations of ground movement, that strains transmitted to well casings, are within tolerable limits of casing specifications. The criteria cater for well barrier pillars in multi-seam mining situations and where previous old mining has taken place. The criteria maintain flexibility in being adaptable to local mine design situations. The criteria are applicable to proposed extraction thicknesses up to 15 feet at depths up to 2,400 feet. The criteria are related to producing wells and to abandoned wells. In the latter connection, various states of well abandonment are recognised.

Jan 1, 1980

By Don Deardorff, Ke Yang, Yingcai Han, Ken Sorensen, Robert Kruger, Mark Petersen, Diane Fiorelli, Larry Goldfarb, Kathryn Petek, Kwabena Ofori-Awuah

Design of deep foundations for lateral loads requires an understanding of soil-foundation-structure response during loading. Lateral loads on a deep foundation (piles) could be due to earthquakes, winds, waves, and/or machine vibrations. Over the years, analysis of response of piles due to lateral loads evolved from closed-form solutions to p-y methods to strain wedge to finite element/finite difference modeling. Although analysis of lateral response of piles and shafts is routinely performed, there is no single guidance document and/or standard for design and testing. Several different analytical methods are available for the analysis, and the resulting design can result in significantly different responses which can create confusion. This is especially true for analyzing and designing piles in potentially liquefiable soils with lateral spread issues under seismic conditions.This guidance document is intended to assist geotechnical engineers, pile designers, and contractors in analysis, design, and testing of piles and drilled shafts for lateral loads. This document discusses the background of different analytical and testing procedures and presents the recommended methods for analysis, design and testing of piles for lateral loads.Chapter 1 defines the different kinds of lateral loads to which a single pile or pile group may be subjected. This first chapter also presents different types of piles used to resist lateral loads.Chapter 2 discusses geotechnical issues related to lateral pile design such as liquefaction and lateral spreading and other non-seismic issues. Also addressed in Chapter 2 is geotechnical site characterization (as related to lateral loads) in terms of site investigation, in-situ testing, geophysical testing, laboratory testing, and estimation of soil/rock properties.Chapter 3 discusses the background and available analytical methods and tools for the analysis and design of single piles and drilled shafts. Several methods of analyses from closed-form elastic solutions to the finite element/finite difference solutions and their applicability are discussed. Available commercial computer software packages for analyzing single piles and drilled shafts are also presented.Chapter 4 expands the discussion of single piles and drilled shafts into the analysis and design of pile groups. In addition, group effects, resistance of pile caps, results of previous experimental and analytical studies, and available analysis tools and software for pile groups are discussed.Chapter 5 presents the issue of lateral resistance of piles and drilled shafts as discussed in different national and international building and non-building codes. A summary of extensive research on several codes are presented to facilitate the compliance with different codes.Chapter 6 discusses structural design issues of individual piles and drilled shafts such as depth of fixity.Chapter 7 discusses soil structure interaction issues related to kinematic and inertial effects due to seismic loading and available methods of analyses.Chapter 8 discusses and presents the typical procedures for the lateral load testing of piles. This guideline was developed as an aid to the practicing engineer in providing information, direction and commentary on the lateral design of deep foundations. Although all reasonable effort has been made to accurately compile the material and information contained herein, no warranty is made with regard to any such material or information and the Deep Foundation Institute assumes no responsibility for any possible errors or any direct or indirect result of the use of any such material or information. It is not intended that this document address every factor affecting lateral design for every situation. Therefore it is the responsibility of the person utilizing information from this document to confirm that it is appropriate and correct for their situation as well as to understand and properly apply

Jan 1, 2012

In presenting this address I am conscious of the honour that has been paid me in my election to this important office, and I am very aware that I follow, in the position of President, many distinguished men who have led the Institute over the 70 years since its inauguration in Broken Hill in 1893.It is perhaps appropriate tonight that I intend to talk about a metal which recalls the birth-place of the Institute, and is also one with which I have had a direct association throughout the whole of my working career. This metal is Silver.Silver is associated traditionally in everyone's mind with money and silverware, and has always been prized for its natural beauty and elegance. It is today one of the few metals in which world consumption has outstripped production, and the events which have occurred to bring about this situation make an interesting story.In telling this story, I propose firstly to indicate our development as a silver producing country, give an historical review of the metal, trace its use as currency and the factors influencing its price, and then say something of the old and new uses of silver. Finally I shall give some comments on silver production in Australia today.Australia, with 6-5 per cent of the world's output of silver, ranks sixth among the producer countries and over the years has contributed 892.5 million ounces to the world's supply which, based upon production since the discovery ofAmerica, is estimated to have been 22,150 million ounces or nearly 680,000 tons.Although our production appears relatively small by...

Jan 1, 1963

By Mandius C. Lundal

This report describes the work done to develop a coal mining machine to increase productivity and recovery from thin seams beyond the highwall, in addition to decreasing the miner's susceptibility to to highwall hazards First, radar transducers were adapted to measure coal thinkness and detect rock and coal interfaces; Then, the radar was incorporated into a cutterhead with steering controls. Next, visual displays were designed to show cutter position in the coal seam, and anticipated change in coal seam inclination, Finally, development of a telemetry system made remote control of the cutterhead possible. Simultaneously, a high-performance extended depth (HPxD) auger machine was designed with an automatic system to handle 600 ft of 36-in, diameter dual spiral flight conveyor sections. A two man crew controls all operations from a weather conditioned cab outside the VDZ, either at night or day time. As a primary mining tool, working 4000 hr/yr (2 shifts/day) recovering 60% of the coal 600 ft beyond the highwall, productlon to 500,000 ton/yr can be achieved. Volume I provides an overview of machine, systems and productivity.

Jan 1, 1977

By D. B. RUSHhIORE

I. INTRODUCTION. OF primary importance in mine-installations is the hoist, which has a very direct bearing on the successful operation of a mine. Conditions vary greatly with different mines, and especially in different localities. Such factors as depth, incline, the number of levels, permissible or desirable speeds, conditions of ore, etc., are always more or less special in each case. Veins of ore are never exactly duplicated, and the nature of the ground through which shafts are sunk may considerably modify permissible values. As mining-laws are made by the different States, they necessarily vary somewhat, and, even when not fully observed, they introduce factors which qualify the conditions of hoisting men and ore. The amount of timbering required is often of importance as relating to hoisting-conditions. Methods of loading ore affect the time required, as also does the question of the use of cars or skips. Safety-precautions must be very carefully considered, and the number of men in each mine, the number of compartments, and often the method of removing water from the mine, must. have careful consideration. While a general discussion of the subject. of hoisting is possible, most cases are entirely special, and can be considered only in connection with the peculiar conditions pertaining to that particular installation. The cost of installation of the hoisting-plant may be an appreciable amount, while the cost of raising the ore may be but a small part of the total operating-charge. In many cases, however, the output of the mine is limited by the capacity of the hoist, and the latter thus becomes of the first importance. * Presented also, by mutual agreement, at the meeting of the American Institute of Electrical Engineers, New York, N. Y., Mar. 11, 1910.

May 1, 1910

By David Gatto, Nicolas A. Willig-Friedrich, Jeff A. Segar

"With the increasing demand for electricity, and requirements to generate this power cleanly, more producers are turning towards hydroelectric power. A project in Iowa currently under construction will retrofit an existing Army Corps of Engineers Dam with a hydroelectric generating facility. The design of the intake structure requires the construction of a diaphragm retaining wall. The T-shaped diaphragm wall elements retain an unbalanced fill height up to 21.3 meters (70 feet). The design required a single production element be constructed, tested, and instrumented prior to beginning construction of the rest of the elements. The testing included extensive concrete mix design development, coring, and Cross Hole Sonic Logging. Installed in the other production elements are 10 inclinometers, 4 pressure cells, 4 piezometers, and multiple survey monuments. Some of these instruments require manual readings while most are monitored by an automatic data acquisition system and instantly transferred to a website providing real-time graphical display of the data. This paper will discuss the construction of the diaphragm wall from the contractor’s perspective when working on a site only large enough for two service cranes and a Hydromill excavation unit, without any storage area on the construction pad, describe the testing performed and the quality control procedures employed, and investigate the information gained from the automated instruments providing real time measurement readings.INTRODUCTIONIn 1964 the US Army Corps of Engineers (USACE) constructed a dam by raising the surface grade approximately 34.7 meters (114 feet) above the natural ground line using a combination of fill types. This earthen dam stretched slightly longer than a mile intersecting the flow of the existing Des Moines River. The center of the dam is a concrete spillway consisting of 12 monolith sections. On each end, three of the sections extend 42.6 meters (140 feet) from the spillway to transition from the concrete dam sections to the earthen dam section. Adjacent to these three sections on the East end is where the contractor is actively working, for a private developer under a lease agreement with USACE, on this site to convert it to a Hydroelectric facility licensed for an output of 36.4 megawatts, enough power to meet the needs of about 18,000 homes. To create this, a powerhouse structure, housing two vertical Kaplan turbines is being added to the downstream side of the existing dam. From the power house, two penstock pipes will be cored through the existing concrete monolith sections and connect to the Intake structure on the upstream side of the dam. Protecting and reinforcing the dam adjacent to the intake structure is a new diaphragm wall. This wall is constructed using T-shaped diaphragm elements, acting as a cantilever retaining wall for the intake platform. Figure 1 shows a diagram of the upstream features of the construction."

Jan 1, 2016

By Bülent Erdem, Zekeriya Duran, Tuğba Doğan

The objective of this study was to evaluate the potential health risk associated with exposure of dozer operators to whole-body vibration. Measurements were made on 31 dozers used in different surface mines in Turkey. Predictions of adverse health effects of vibration were based on the standards BS 6841:1987, ISO 2631–1:1997, ISO 2631–5:2004, and the EU Vibration Directive:2002. Operators experienced high and comparable levels of vibration acceleration and dose during all dozer tasks: pushing the material (DOZE), moving forward (FORWARD), moving backward (REVERSE), and ripping (RIP). Specifically, DOZE, FORWARD, REVERSE, and RIP showed high potential of adverse health effects in terms of vibration dose according to the worst-case axis and vector sum criteria and a moderate adverse health effect for acceleration according to the worst-case axis criterion. Operators of large dozers were exposed to lower levels of vibration. However, no statistically significant relationship between vibration exposure levels and the propelling mechanism and the service time of dozers, operator experience, operator age, and ground type was found.

Jun 16, 2022

This paper is intended partly as a summary of the conclusions that have been arrived at by various authorities on this matter, and also with a view to initiate some discussion on the subject, especially as most of the quartz gold mines in Victoria are operated without having any proper assay plans or any idea of the real values other than those given by the mining managers, who, from experience in the particular cases, are supposed to be able to arrive at a correct idea of the true values of- the ore, and, in many cases, oppose any other methods than their own, holding the view that no sampling is equal in correctness to the bulk sample of the battery. The necessity of properly sampling and estimating the ore in a mine in every case, perhaps hardly needs to be urged on the members of the Institute, but is not, apparently, so obvious to others.It is proposed to confine this paper to the sampling of ore reserves in a mine, and the various points which have to be taken into consideration in arriving at values, from the assayer's point of view, leaving the methods of sampling metallurgical products out of consideration for the present. "It is advisable to define" ore reserves" as ore exposed on three sides at least, and accessible to the sampler on all three. "Prospective ore" would include all ore not so fully exposed; but which may, from the nature of the case, and the geological conditions prevailing, be reasonably supposed to exist.

Jan 1, 1904

The Bureau of Mines human factors research program is directed toward reducing accidents and improving the overall efficiency of the person-machine environment interface found in surface and underground mines. The focus of the hum factors program therefore, is to insure that sound knowledge is available concerning human capabilities and limitations, and that this knowledge is applied to the design, of mining equipment, work tasks, and management procedures. The papers presented in these proceedings summarize some of the recent Bureau research in hum factors. The papers focus on two broad areas, human resource issues and human engineering of equipment, tools, and work procedures found in mines.

Jan 1, 1987

By Charles W. Briggs

The steel foundries of Germany were investigated for the purpose of ascertaining (1) the type and classification of steel structures produced as castings, (2) processing methods, (3) the mechanical properties of carbon and alloy cast steels, (4) the type and character of defective castings, (5) the appearance of castings, (6) research in steel castings, and (7) plant lay-out and equipment.

Jan 1, 1946

By A. L. Murray

First -aid training as an adjunct to safety is receiving more wide spread recognition in the industries every year . Moreover , the adoption of a program for giving firstaid training to practically all employees at a mine or plant is based upon the experience gained and good results obtained from standard first -aid instruction during the past two decades . In the near future industries that desire to maintain a low accident rate , to decrease compensation costs , to reduce lost time , and to build up an efficient , loyal working force , will recognize that training in first aid is one way of attaining these results with little expenditure of time and effort . Progressive organizations will require every man from the superintendent down to take first - aid training and not , as heretofore , only a small percentage of the working force . When employees learn that first - aid training can be applied not only at their daily tasks but in their homes and on tthhee highways ,, they will welcome the opportunity of learning how to care for injuries and perhaps save lives . In a limited way first - aid instruction was given to miners as early as 1899 . Later , in 1904 , a few of the companies in the Pennsylvania anthracite district inaugurated the distribution of first - aid packets to their employees and instructed them in the use of the contents . It remained , however , for a branch of the United States Government to grasp the real significance of widespread first - aid training as an effective means of saving life and minimizing suffering from the large number of accidents among workers in the mineral industries . The United States , owing to its vast resources , both natural and human , for

Jan 1, 1930

By Alfred Bodenlos

El presente artículo describe la historia geológica pre-cretácica de la Cordillera Negra. En algunos intervalos predominaron los pantanos que dieron lugar a la formación de carbones. Luego, en el Valanginiano superior, la región estuvo sumergida, depositándose calizas delgadas. Los tufos que yacen sobre la secuencia de elásticos indican que hubo actividad volcánica a fines de este intervalo. Parte apreciable de los depósitos marinos del Cretácico medio está formado por calizas bituminosas obscuras.

Jul 1, 1957

By Leroy E. Schulze

A review of development and a reevaluation of uses of the hydraulic air compressor are suggested by the constant changes in technology, which frequently make an old art valuable in solving current problems. Contacts with research workers in various branches of engineering indicate that this older method of producing compressed air may not be familiar to some or that its salient features might be useful in solving problems involving uses of compressed air. Briefly, a hydraulic air compressor may be described as an inverted siphon, consisting of an intake head where water and air are mingled, followed by a gravity-fall tube in which air is intimately mixed with the water and is compressed as the water pressure increases during the fall down the tube, then a separating, or stilling, chamber in which air bubbles rise to the surface of the water and collect in the upper portion of the chamber at a pressure equal to the weterhead maintained by the height of water in the discharge leg of the circuit. The water, which now contains only the fraction of air that has gone into solution, passes out of the separating chamber and rises up the discharge leg to the surface, which is, of course, at some suitable distance below the level of the intake. Present-day applications include (1) utilizing low hydraulic heads, which otherwise have little commercial values; (2) utilizing low hydraulic heads in reclamation work to supply compressed air, or in some instances to produce a small suction, for air-lift pumping (or for operation of air motors), with minimum attendance and without need for electric power; (3) utilizing medium heads, as at dam and lock installations, to produce compressed air for pneumatic operation of airlifts, gates, valves, and rubber gate seals; (4) utilizing underground waters, as in mines, to produce compressed air for general mine use; (5) using this method of isothermal compression of air in combination with standard compressors wherever hydraulic head is available, thereby securing the advantages of low-temperature intake to the mechanical compressors and reduction of moisture content below that of atmospheric air; (6) development of large air supply at pressures up to 150 p.s.i.g., which, after performing work in reciprocating or centrifugal expansion cylinders, is available at temperatures approximating -50° F. Possibilities in freezing and reheating should be mentioned which may prove economical for obtaining uniformly dry air for process work, wind-tunnel tests, or large air-conditioning installations, such as ventilation of underwater traffic tunnels, and may be economic for supply of supercharged air to gas-turbine plants.

Jan 1, 1954