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This chapter summarizes data on crude mineral production for the United States, its island possessions, and the Common-wealth of Puerto Rico. Included also are tables that show the principal mineral commodities exported from and imported into the United States, and that compare world and U.S. mineral production. Except for the mineral fuel commodities, 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. In October 1977, responsibility for the collection of data on mineral fuels-coal, petroleum, natural gas, and natural gas liquids-was transferred to the newly created Department of Energy. Although chapters covering these commodities will no longer appear in Volume I of the Minerals Yearbook, quantity and value data have been included in most of these summary tables to maintain statistical consistency in State and national value of overall crude mineral output. This shift in responsibility has also resulted in changes to the composition of the "Nonmetals" and "Mineral Fuels" groups in table 1 and table 2. The commodities-asphalt and related bitumens (natural), carbon dioxide (natural), helium, and peat-have been removed from the "Mineral Fuels" group, and are now included under the "Nonmetals" group. There has been no change in the components of the "Metals" group.

Jan 1, 1980

By Peter Jackson

The dewatering of the large construction pits required for major infrastructure projects often has a significant impact on the environment. This is particularly so in urban areas and where groundwater resources are of interest. These environmental impacts are inter alia, groundwater lowering and the consequent effects such as settlement and deterioration of timber foundations, together with the impact of the dewatering on the groundwater quality. In order to minimise the environmental impact of the dewatering, the quantity of water to be abstracted and the amount of groundwater lowering in the surrounding area must be minimised. This paper describes the measures that have been taken on the Copenhagen metro project to achieve the objective of minimal environmental impact whilst still carrying out a major dewatering scheme.

Jan 1, 2000

By R. A. Welsh

The Bureau of Mines has developed a photoelectric concentrator apparatus which is capable of collecting incremental products from the discharge of wet concentrating tables. The instrument uses photoelectric cells as sensors to differentiate between two products which have differences in color or reflectivity. The photocells provide a signal that controls a mobile splitting device that separates the products. Tests conducted on a wet table demonstrated the ability of the apparatus to separate a product containing 81.5 percent pyrite from a lower-grade product containing only 68.8 percent pyrite. The photoelectric concentrator should have a broad application for collecting concentrates with visible color or reflectivity differences from wet concentrating tables.

Jan 1, 1972

Operating well designed and maintained surface mine haul roads is the key to minimising truck haulage costs - in itself a significant component of the total cost per tonne mined. Existing and proposed mining operations are subject to scrutiny, both from the economic and environmental perspectives. In the long run, this scrutiny returns improved efficiencies and leaner, 'greener' operations. The focus of this evolving evaluation process should and will certainly fall on haulage operations - simply by virtue of their contribution to overall cost of operations and sustainability impacts. Whilst the end result - improved efficiency and contributions to resource sustainability - is not in itself problematic, it is the route, or process followed to achieve these improvements that needs to be carefully managed. We can be guided on this journey by our understanding of how a road is designed, and, critically, the technological solutions that can contribute to a company's sustainability initiatives. This paper examines the current state of mine road design and operation, together with the economic and environmental issues associated with under-performance. The paper serves as a basis for evaluating the economic and environmental contributions that technology in road design and management can deliver to sustainable operations. Utilising innovation is the key to long-term sustainability and as a means of positioning the industry for the imminent structural changes to the economy and environment, changes which are now within the operating life of many mines, haul roads and haul trucks.

Jun 1, 2010

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 U. Singh, E. T. Brown, J. Coxon

The rapid fracturing and deformation that occurs around excavations during rock bursts demand that support and reinforcement systems have both deformability and damping capabilities. The energy demand and supply approach currently used in design is considered to be too simplified to represent adequately the rock burst process and the support and reinforcement system requirements. Momentum change may be a necessary second criterion for the analysis of dynamic loading situations. At the St Ives Gold Mining Company, DE plates made from conveyor belt rubber, and dynamic cables with sliding anchors have been developed and used to improve the dynamic performance of support and reinforcement systems. La fracturation rapide et la déformation qui se produisent autour des excavations lors de coups de terrain demandent que les systèmes d’armature et de support soient déformables et aient une capacité d’amortissement. L’approche basée sur l’énergie actuellement utilisée pour la conception est considérée être trop simplificatrice pour représenter adéquatement les coups de terrain et les paramètres de conception des systèmes d’armature et de support requis. Le changement de quantité de mouvement pourrait être un second critère nécessaire pour l’analyse des cas de charge dynamnique. St Ives Gold Mining Company a développé et utilisé des plaques « DE » constituées de caoutchouc de courroie de convoyeur et des câbles dynamiques avec ancrage coulissant afin d’améliorer la performance dynamique des systèmes d’armature et de support. Die ploetzliche Rissbildung und Verformung, die sich in Baugruben waehrend eines Felseinbruchs ereignet, verlangt Stuetz- und Verstaerkungssysteme, welche verformbare und mildernde Eigenschaften aufweisen. Die derzeitlich gebraeuchliche Methode den Entwurf auf den Energiebedarf und dessen Abdeckung zu basieren, wird als eine unannehmbare Vereinfachung betrachtet, da sie den Felseinbruch und die benoetigten Unterstuetzungs– und Verstaerkungssysteme unzulaenglich darstellt. Die Aenderung der Umstaende kann einen zweiten Ansatz fuer die Analyse der Lastsituation erforderlich machen. Die St.Ives Gold Mining Company hat DE Platten aus Foerderband-Gummi und elastischen Kabeln mit verschiebbaren Verankerung entwickelt und dazu verwendet, die dynamische Kapazitaet der Unterstuetzungs- und Verstaerkungssysteme zu verbessern.

Jan 1, 2003

By K. Short

Over the past several years, the mining and minerals market was overloaded with discussions around reviving mature terminologies like distributed control systems (DCS), programmable logic controllers (PLC), and the ?new comers?: hybrid control systems (HCS) and programmable automation controllers (PAC) and, in parallel, which technologies would be more appropriate for mining and mineral processing applications. Ten years ago, a careful comparative analysis would make more sense. Control approaches had very distinctive differences where users needed to choose the right approach.

Jan 1, 2012

By P. Massi

"Wholly owned by the Coniagas Mining Company, the oldest continuously listed mining company on the Toronto Stock Exchange, St. Andrew Goldfields is located on Hwy. 101 approximately 30 miles east of downtown Timmins, Ontario. Geographically situated on the Porcupine-Destor Fault, the mine and mill in Stock township is positioned in the heart of Northeastern Ontario's goldmining communities.In July 1988, a 600 ft. shaft, hoist, and compressors were already in place when construction started on a 500 T.P.D. capacity C.I.P. mill and crushing plant.By June 15, 1989 the mill was commissioned and attained the design capacity by August of that same year. Since then, changes to the circuit have increased throughput to 900 T.P.D. from two significantly different ore sources.Meeting the Ministry of the Environment's guidelines is an ongoing commitment utilizing the Inca S02 process in line between the tailings pond and secondary polishing pond.INTRODUCTIONExploration on what is now known as St Andrew Goldfields' Stock Township Mine was carried out ln the early l960 1 s by Hollinger Mines Ltd. The property was acquired by Quebec Sturgeon River Mines 1n 1973 and the main shaft was started ill 1979.When St Andrew Goldfields was incorporated 1n 1983, exploration and development commenced to identify the ore body. The company decided 1n 1987 to bring the Stock township property into production after an extensive feasibility study and testwork at Lakefield Research in Toronto. Leslie Engineering was contracted to design, engineer and procure al 1. equipment from the coarse ore bin to the tailings distribution system and backfill plant"

Jan 1, 1992

By Moorrees C, Everson P

A detailed examination of carbonic acid leaching of crude iron-containing magnesia derived from Savage River magnesite shows that the rate and extent of magnesium and iron dissolution are affected by the slake time, leaching temperature, carbon dioxide pressure, pulp density and rate of agitation. In order to produce high-purity magnesia from the leachate by precipitation and calcination, the optimum leaching conditions, which are those that yield maximum magnesium and minimum iron dissolution, have to be a compromise in terms of the above parameters. For example, iron dissolution can be limited by leaching at an elevated temperature (-45°C), but because the maximum concentration of magnesium biearbonate decreases rapidly with an increase in temperature, it is necessary to use a low pulp density (-2 per cent solids) in order to achieve an acceptable degree of magnesium dissolution.Evidence is obtained that iron dissolution involves the formation of a soluble ferric bicarbonate complex that decomposes at elevated temperatures. The extent of iron dissolution is much higher than might be expected and it is probably because the original magnesite contains siderite in solid solution with the magnesite; on calcination, the hematite whieh is formed is in a very finely divided condition and hence more reactive.

Jan 1, 1983

By N. Kumar Kittusamy

The purpose of this study was to assess the adequacy of the cab design and to determine the percentage of musculoskeletal symptoms among operators of mobile equipment used in mining and construction. A questionnaire was designed to assess demographics, work information, job history, and musculoskeletal symptoms in operators of heavy mobile equipment. Information concerning equipment included design of the seat/chair, levers, pedals, bothersome vibration, quality of ingress/egress from the equipment, proper preventative maintenance and repairs, and age of the equipment. The body regions that were evaluated included the neck, middle/upper back, low-back, shoulder/upper-arm, elbow/forearm, wrist/hand, hip, knee, and ankle/foot. Five hundred and eighty six operators completed the questionnaire. The results indicate that these workers are at risk for developing musculoskeletal disorders, and the need to quantify risk factors (i.e., whole-body vibration and static sitting postures).

Jan 6, 2006

By M. Nete

Qualitative analysis of three mineral samples from northern Mozambique was accomplished by X-ray diffraction (XRD), microscopy, scintillation, and magnetic determination. Chemical characterization was accomplished using ICP-OES and pressed powder XRF after dissolution using microwave-assisted digestion and flux fusion. The samples consisted of a mixture of minerals with tantalite as the major component, with minor amounts of microlite, quartz, mica, accessory garnet, and tourmaline. Incomplete dissolution was obtained using microwave digestion, with maximum recoveries of 90.25 ± 0.06% and 88.90 ± 0.04% for Nb2O5 and Ta2O5 respectively. Complete dissolution using Li2B4O7 resulted in recoveries of 98.5 ±0.2% Nb2O5 and 100.4 ± 0.3% Ta2O5.

Jan 1, 2012

By Maurus Seet Hong Hua

Introduction Coal has always been China's predominant energy resource. The country ranks among the three richest countries in coal reserves in the world, next to the US and the Soviet Union. According to China's Ministry of Coal Industry (MCI), coal accounted for about 72% of the total national energy consumption. Despite efforts to increase the output of oil and hydropower, coal is predicted to remain dominant on the energy scene by increasing its share to 77% by the turn of the century. To match the rapid growth in the agricultural and industrial sectors, MCI has targeted the coal industry to double coal output from 600 Mt/a (660 million stpy) in 1981 to 1.2 Gt/a (1.3 billion stpy) by the year 2000. How is this goal to be achieved? According to MCI, it will be accomplished by: • building new underground and surface mines with a total output of 400 Mt/a (440 million stpy); • increasing the output of existing state-controlled mines from the present 344 Mt/a (368 million stpy) to 400 Mt/a (440 million stpy); and • developing and increasing the output of small, local mines run by province, county, and production brigade from the present 276 Mt/a (304 million stpy) to 400 Mt/a (440 million stpy). Building new underground and surface mines New underground coal mines will be developed in areas where the coal industry has already made headway and infrastructures currently exist. This is to optimize hardpressed capital spending on investment. Ten existing coal production bases were selected in nine different provinces that met these requirements. The underground mines scheduled to be constructed in stages at he existing coal production bases will have a total output of 200 Mt/a (220 million stpy) by the end of the century. Regarding surface mines, four mines in the Inner Mongolia Autonomous Region and one in Shanxi province have been earmarked for construction during the same period. By the year 2000, these surface mines are expected to produce 200 Mt/a (220 million stpy). Foreign equipment, machinery, and surface mine stripping technology were all involved in different degrees in the development of the five new surface mines. Some have signed joint venture agreements. Occidental Petroleum Corp. is in a joint venture with China in developing Ping-shou's 15 Mt/a (16.5 million stpy) Antaibao No. 1 open-pit. The Shentou power station, situated nearby, is anticipated to consume 3.2 Mt/a (3.5 million stpy) of the coal it produces. Some is designated for export. Increasing output There are 554 state-controlled mines that have been in operation since before 1980. They produce 344 Mt/a (379 million stpy). To increase capacity, MCI has laid out some guidelines. • Coal prospecting near existing mines must be given top priority and intensified so that workable reserves can be increased. This would lengthen the mines' useful life. • Many mines and slopes that were constructed during the 1950s are very small and densely populated. These small mines and slopes are generally very short along the strike. As a result, coal faces and levels require frequent

Jan 3, 1986

By Andrew Jones

This paper discusses the worldwide market and cost environments for the bulk ferroalloys namely manganese alloys (ferromanganese, silicomanganese), ferrosilicon and ferrochrome (high-carbon ferrochrome, charge chrome). Annual average market prices since 1993 are presented graphically and analysed, and the main supply and demand trends for manganese, ferrosilicon and ferrochrome are summarized. The paper shows carbon and stainless steel output data for 1995, 2000 and 2005, mainly to demonstrate the rising importance of China as a ferroalloys market. Developments in ferroalloys capacity worldwide from 1991 to 2007 are discussed (plant start-ups and closures, ownership changes). Finally, the paper examines developments in the main cost factors for the bulk ferroalloys, i.e., chrome and manganese ore, electricity, carbon reductants and labour. Note that data for 2006 are estimated based on information available in November 2006.

Jan 1, 2007

By A. M. Khan, I. Fatt

A new type of steady-state thermal conductivity apparatus is presented and described. Results of measurements on Berea sandstone, Solehofen limestone, Bandera sandstone and Bakelite are presented. The measurements were made in a two-hour period at temperatures up to 80C and axial stress to 125 bars. Results show that the thermoelectric heat pump and tbermistor-controlled electric heater can be used in a steady-state apparatus for measuring thermal conductivity of mck. Steady-state is reached within two hours. With Urethane foam insulation, not more than 3 per cent of heat is lost by radial flaw. The apparatus can be used as a comparator or for absolute thermal conductivity determinations. INTRODUCTION Calculations of heat flow through the earth, both for scientific purposes and engineering design, require thermal-conductivity data on rock. However, the high variability of rock often makes handbook thermal-conductivity data of little value. For engineering purposes in particular, it is desirable to have measured data on samples of the rock mass under study. Laboratory methods for measuring thermal conductivity of rock use either time-dependent1-3 or steady - state temperatures .4,5 The time -dependent (transient) techniques give thermal diffusivity from which thermal conductivity can be calculated if the specific heat and density of the sample is known. Most transient techniques require lengthy and involved sample preparation. Also, the accuracy tends to be low. Steady-state techniques are more exact and are the most commonly used. The steady-state methods, however, also have their difficulties. A long time is often required to reach steady state, troubles have been encountered in establishing good thermal contact between the heating and cooling elements and the rock sample, and unaccounted-for heat losses are difficult to prevent. In this paper we present a description of a new type of steady-state thermal conductivity apparatus. With it, measurements have been made in two hours at temperatures up to 80C and axial stress to 125 bars. Sample preparation is simple and no thermal conductivity standard is needed.6 APPARATUS Our steady-state apparatus is an improvement . over the conduction pile used by Zierfuss and van der vliet4 and Somerton.5 A linear heat flux is established through a conduction pile consisting of the rock sample and a standard material of known thermal conductivity in series. The thermal conductivity of the sample is calculated from the ratio of the temperature drop across the sample

Jan 1, 1966

By Anthony D. Hammond

The use of geographic information systems (GIS) as a tool to analyze and display data is gathering momentum in the mining industry. Of particular interest is the capability of GIS to link spatial features and tabular data. The application of GIS in underground mining discussed here concentrates on four technical areas. They are land ownership and mineral claims, exploration management, production and mine safety.

Jan 1, 2002

Eight members of the Board, the Secretary of the Institute, and eleven guests were present. Vice-president Henry S. Drinker presided. The President was authorized to appoint delegates to a meeting, on May 16, of the League to Enforce Peace. The Joint Conference Committee reported that the American Institute of Metals had accepted the invitation to form the Institute of Metals Division of this Institute. The Committee on Publications of the Institute of Metals was added to the Committee on Publications of the A. I. M. E. Exchange of one volume of Transactions of the A. I. M. E. at reduced price to members of the British Institute of Metals was authorized, in return for the reduced price given to our Institute of Metals Division on the annual proceedings of the British Institute.

Jan 6, 1918

Session 1 ? Intro to MiHR ? Business Case for Aboriginal Inclusion ? Overview of the Mining HR Guide for Aboriginal Communities ? Two presentations of Programs featured in the Guide ?? The RAP Program from NWCC ?? First Nations Youth Employment Program PDAC-MM Session 2 ? Presentation from MAC ? Taking up the AFN Corporate Challenge ? Presentation on Mastering Aboriginal Inclusion in Mining About MiHR Who we are: ? National Sector Council for the Minerals and Metals Sector ? 18-person Board of Directors ? 100+ Industry Leaders volunteer on our project committees ? PPP - Funded by HRSDC and industry What we do: ? Identify national HR challenges and opportunities for the minerals and metals industry ? Create national solutions through collaboration, partnerships and Synergy

May 1, 2009

There were present twelve- Directors, the Secretary and the Assistant Secretary of the Institute, and fifteen guests. A committee of three was appointed to draft a suitable resolution of memorial of the services of Joseph Esrey Johnson, Jr. The committee consists of Joseph W. Richards, Chairman, J. V. N. Dorr and Allen H. Rogers. William R. Walker was elected a Director in place of J. E. Johnson, Jr., and Edwin Ludlow was elected a member of the Executive Committee in his stead. George C. Stone was appointed Chairman of the Committee on Membership in place of Mr. Johnson. The following resolutions were then adopted: RESOLVED, That a special business meeting of the Institute be and the same hereby is appointed to be, held at the office of the Institute, No. 29 West 39th Street, Borough of Manhattan, City of New York, on the 27th day of June, 1919, it 8.30 o'clock in the P. M. to consider and take action upon the proposal to change the name of the Institute to "American Institute of Mining and Metallurgical Engineers, Incor-porated," and the further proposal to extend the corporate purposes of the Institute so that it shall, in addition to its other powers, be empowered to promote the arts and sciences connected with the economic production of the useful minerals and metals, and the welfare of, those employed in these industries, by all lawful means.

Jan 6, 1919

By H. J. Sutherland

This paper reviews the results of the subsidence research prop ram at Sandia National Laboratories. The manuscript highlights the following: the application of empirical methods (profile functions) to the subsidence above longwall panels in the U.S.; the use of the "rubble model" to describe the behavior of broken strata as it distends when it falls to the Mine floor (or top of the rubble pile) and then is subsequently compacted as it is loaded by overlying elements of strata; and, the application of physical modeling techniques (centrifuge simulations) and numerical techniques to study the failure mechanisms in highly structured stratigraphy. The capabilities of the latter two are illustrated ')y comparing their predictions to the results of a field case that has complicated stratigraphy.

Jan 1, 1982

By David R. Beadman

This paper discusses how modern techniques of design and construction were used to create the deep stations for the Copenhagen Metro. The deep stations are located in small squares within the city adjacent to many old and sensitive buildings. The architectural design provides a large open atrium to allow natural light to reach the column free platforms to give the citizens of Copenhagen a feeling of safety and security and encourage them to use the Metro. The design and construction contract was undertaken using the relatively new and untried Eurocodes. The resulting stations set new standards of design for underground metros and have pushed forward the frontiers of what is appropriate construction practice to protect the existing and enhance the future environment.

Jan 1, 2000