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By G. Roger Miller, Kristine M. Krajnak, Stephen S. Leonard, Stacey Waugh

Repeated exposure to hand-arm vibration through the use of vibrating hand tools can result in the development of the disorder known as hand-arm vibration syndrome (HAVS; (1,3)). One of the hallmark symptoms of HAVS is cold-induced peripheral vasospasms that result in finger blanching (4). Although the vascular and neural pathology associated with vasospasms has been described, little is known about cellular mechanisms leading to this damage (4). To understand how vibration may alter vascular and neural physiology and anatomy, rats were exposed to a single bout of tail vibration and the molecular responses of neural and vascular tissues were measured to determine if there are immediate or sustained affects of vibration that may underlie longer term changes in physiology. Methods Experiment 1. Male Sprague Dawley rats (n = 32, 6 weeks of age) were housed in AAALAC accredited facilities. All procedures were approved by the NIOSH Animal Care and Use Committee and were in compliance with the CDC guidelines for care and use of laboratory animals. Vibration exposures were performed by restraining rats in Broome-style restrainers, and securing their tails to a vibration platform using 6 mm wide straps that were placed over the tail every 3 cm. Restraint control rats were treated in the same manner, except that the tail platform was mounted on isolation blocks and not on a shaker. The vibration exposure was 125 Hz, 49 m/s2, for 4 h. Rats were euthanized with an overdose of pentobarbital (100 mg/kg) 1 h or 24 hours after the exposure. RTqPCR was used to measure transcript levels for endothelin 1 (ET-1), the 3 forms of nitric oxide synthetase (NOS) NOS-1, NOS-2, NOS-3 and norepinephrine receptor subtypes 1D, 2A, 2C, in artery tissue, and to measure calcitonin gene-related peptide (CGRP) and nitric oxide synthase-1 (NOS-1) in ventral nerves. Data were analyzed using 2-way ANOVAs. Experiment 2. Male Sprague Dawley rats (n =24, 6 weeks of age) were maintained as described above. Animals were exposed to a single bout of restraint or vibration. Another group of animals served as cage controls. All animals were euthanized 24 h after the exposure, and tail arteries were isolated and frozen. Reactive oxygen species ROS) were measured using electron spin resonance spectroscopy (ESR). Arteries were homogenized over ice in 1 ml of PBS with protease inhibitor cocktail, using a tissue tearer (Biospecs Products Inc. Racine, WI USA). The sample was split into two 0.5 ml samples. One set had PBS and the spin label hydroxyl-TEMPO [0.1 mM] added while the other set had hydroxyl-TEMPO [1.0 mM] plus the specific hydroxyl radical scavenger, dimethylthiourea (DMTU), added to confirm the presence of the hydroxyl radical. Samples were vortexed and then placed in a flat cell for ESR analysis. The ESR spectrometer settings were: receiver gain, 6.32 x 102; time constant, 0.02 s; modulation amplitude, 1.0 G; scan time, 20 sec; magnetic field, 3490 ± 100 G (2). Data were analyzed using 1-way ANOVAs.

Jan 6, 2006

By Kung-Lee Wang

This report describes the linkage of all mining sectors with all other manufacturing, services, and final demand sectors of the U.S. economy. Besides being a basic data source, it provides a framework for aggregate economic impact analysis with respect to the mining industries. The framework is an open-static input-output model specifying 48 mining industries as classified in the Standard Industrial Classification Manual for all mining activities and 76 nonmining industries which collectively exhaust, all economic activities. The 124-sector model used in this report is an expansion of the preliminary 82-industry aggregation estimates made by the Department of Commerce. In the expanded model, 48 ruining industries are substituted for the original 6. The methodology used to ascertain the industry-by-industry procurement cost estimates and product ion flows necessary to the construction and expansion of the basic 82-sector model included personal interviews, case studies of specific mining activity analysis, and published and unpublished data from the Bureau of Mines and the Census of Mineral Industries, The end products of this study are two tables arranged to show the direct purchases necessary for each industry to support the level of economic activity and the total purchases generated in each industry throughout the economy by each $1 of aggregate economic demand in 1958. The tables may he used for economic impact studies and market analysis by firms engaged in or closely associated with the mining industries. Some illustrations of their usages are presented.

Jan 1, 1967

By Luis v. Coppa

Since its inception in 1910, the Bureau of Mines has been the principal Federal agency involved in ore reserve estimations, using such traditional methods as polygons of influence and variations of inverse distance weighting While adequate for estimating the average are grades in a mining block or section, these methods do mot, however, provide a consistent way of quantifying the reliability of the estimates. This report describes a technique for enhancing ore reserve estimations using geostatistics, the methodology of which combines the spatial and random aspects of geologic phenomena into a formal theoretical framework for deriving the estimation variance of ore reserves. Correctly used, geostatistics enables confidence intervals to be placed around ore reserve estimates calculated from drill hole data. A geostatistical software system was obtained -From the U.S. Geological Survey and installed, aster slight modifications, on the Bureau's Wang computer. System testing and validation was conducted using a simple cast-book-type example. This was then followed by variogram analysis, point kriging and block kriging of data from a previously worked section of a uranium mine.

Jan 1, 1984

By George G. Goble

The use of augercast piles has been limited by the engineer's concern for the structural quality of the installed pile. The nature of the pile is such that its final structural continuity is very dependent on the skill of the personnel that do the installation. Thus, NDT methods have been used to verify integrity and when problems are indicated the available solutions are usually quite costly. If information were available during the pile installation so that immediate steps could be taken to correct perceived problems, the concerns of the engineer could be addressed and the system would gain increased reliability. Pile Dynamics, Inc. has developed a quality control system, the Pile Installation Recorder for Augered Cast-in-Place piles (PIR CFA). This system consists of the following devices as shown in Figure 1. 1) The Control Unit powers the sensors, conditions the signals from the sensors, records all measurements, takes input information from the operator, displays the results, and stores the recorded data on a flash card for later permanent storage and processing. During the use of the system all of the results obtained during a test are seen during recording and can be reviewed on the screen again after completion of the installation. The ability to review the measured information makes it unnecessary to print a copy in the field. Since printers often give difficulty in the construction site environment the ability to review the results quickly after completion of the installation is an important capability.

Jan 1, 1997

By A. Butler

This paper explains the politics of mine nationalization in contemporary South Africa. Nationalization and privatization typically occur in the oil, mineral resources, and state utilities sectors, and they tend to follow one another in a long-term cyclical pattern. The paper explains why the current international environment has encouraged demands for nationalization and other forms of ?resource nationalism? in the South African minerals sector. It goes on to describe how the resurgence of resource nationalism has been influenced by internal factional politics in the African National Congress. It concludes that nationalization is unlikely to be the outcome of current policy deliberations within the ANC.

Jan 1, 2013

By Michel R. Julien, Michel Lemieux, Jean Cayouette, Daniel Talbot

"The Louvicourt Mine located near Val d’Or, Quebec has been in operation since 1994. It produces copper and zinc concentrates. The tailings generated from the ore processing operations have a strong net acid generating potential. Louvicourt Mine, a grass root project, was designed for closure with the best available technology at the time of design. In order to inhibit short and long time acid potential generation, sub-aqueous disposal was selected at the design stage. Given the fact that disposal in a natural lake was ruled out up front for obvious reasons related to loss of natural habitat and risks of permitting delays, a man made facility built with dams was planned. This mine includes therefore the first fully man-made sub-aqueous tailings disposal facility built in Canada. The requirement of using sub-aqueous disposal had serious implications on the placement of tailings. This tailings facility located about 9 km from the mine site has been selected based on the available natural confinement, the favorable foundation and hydrogeological conditions. This paper describes the site and the design criteria that were used. A presentation is also made on the placement technique to maximize storage and its impact on the operation of the basin. The performance of the basin, the dams and the decant structures is reviewed.Résumé : La mine Louvicourt, située près de Val d’Or, Québec est opérationnelle depuis 1994. Elle produit des concentrés de cuivre et de zinc. Les résidus générés par les opérations de traitement du minerai possèdent un fort potentiel net de génération d’acide. Le parc à résidus de la mine Louvicourt, implanté dans un milieu naturel intact, fut doté dès sa conception initiale de la meilleure technologie de fermeture disponible à l’époque, soit la déposition sous couverture aqueuse et ce, dans le but de bloquer le potentiel de génération d’acide à court et à long terme des résidus. Etant donné que la déposition dans un lac naturel fut mise de côté dès le départ pour des raisons évidentes reliées à la perte d’habitats naturels et au risque d’introduire des délais dans l’émission des permis, un étang artificiel délimité par des digues a été conçu. Cette mine fut donc la première au Canada à être dotée d’une installation anthropique de disposition des résidus sous une pleine couverture aqueuse. L’exigence d’une déposition sous couverture aqueuse a eu des implications sur le mode de mise en place des résidus. L’emplacement de l’installation de gestion des résidus a été choisi en un lieu situé à environ 9 km du concentrateur sur la base du confinement naturel disponible et des conditions hydrogéologiques et géotechniques favorables. Cet article décrit le site et les critères de conception utilisés. Une présentation est faite sur la technique de mise en place utilisée pour maximiser l’entreposage et son impact sur l’opération du bassin. La performance du bassin, des digues et des structures de décantation est également revue."

Jan 1, 2004

By P Wopereis

The Nokomai valley is located within the pumpellyite/actinolite facies of the Otago Schist, a regional scale metamorphic belt in Southern New Zealand. The Otago Schist is dominated by psammitic and pelitic greyschist with more subordinate greenschist, quartzite, marble, and ultramafics. Mining in the Nokomai, began in the 1860s, with sluicing of terrace gravels in the lower valley. Good gold is reported to have been won from unconformities within very weathered gravels lower in the terrace sequences, and particularly from within channels which dissect these older deposits. Gold was recovered from these terraces in the main Nokomai Valley, and two major tributaries (Victoria Gully and Bullock Head Creek). In the period 1885 - 1887 further gold was discovered in basal gravels beneath the Nokomai flats when the Hunter brothers sank two shafts and excavated a connecting drive to discover a lead 1.2 - 1.5 m thick. The Golden Lion Sluicing Company began mining in 1896 using an hydraulic elevator on the very 'tight' 1.8 - 2.4 m of basal gravels. This operation was followed by the Nokomai Gold Sluicing Company whose average return grade was >485 mglm3 until mining ceased in 1943 (Wopereis; 1988, 1989). A quartz vein, Commissioners Reef, was worked for small production at some time during the 1920 - 1930 period, until fault termination of the vein ceased production.

Jan 1, 1996

By P. Grainger, P. G. Kalaugher

Paper presented at conference and first published in preprint volume of: Risk assessment in the extractive industries, held in University of Exeter, 23-24 March 1994. London: IMM, 1994. Large, unpredicted ground movements resulting from open cast or underground mining present risks to the safety and economy of extractive industries. As large, sudden failures are usually preceded by small displacements at a much slower rate, the detection and monitoring of these minor changes to the ground surface provides a means of assessing the risks. It is recommended that a visual approach is often preferable to surveying or fixed instrumental measurements. An optical system has been devised, incorporating a 35 mm camera, which allows an immediate comparison on site between a colour transparency taken on a previous inspection and the scene it represents. The observer fuses the transparency stereoscopically with the directly viewed scene. The impression is close to that of normal vision except that differences in detail which have occurred since the transparency was taken are immediately obvious, enabling a qualitative assessment of changes to be made on site. If repeat photography is required it can be taken with exactly the same alignment and coverage. The two images are then available for office analysis using simple micro-photogrammetry

Apr 1, 1996

By Peter Townsend, Sergei Diachenko, Allan Moss

The Palabora Mining Company has successfully extended the life of its operation by developing a 30,000tpd block cave underground mine below the now closed open pit. The process of transitioning from surface to underground mining has been technically, operationally and managerially challenging. This has been due to a number of factors; in particular, the development of a block cave in a very competent rock mass. The competence of the rock mass is clearly demonstrated in the open pit that preceded the block cave, one of the steepest deep open pit excavations in the world. With cave breakthrough, however, the pit was ?instantaneously? deepened by 400m causing a major failure of the northwest wall involving close to 100Mt of waste material.

Jan 1, 2006

INAP was formed in 1998 by a number of major mining companies, with a view to sharing acid rock drainage knowledge and experience, and to coordinate global research on the management of sulfidic mine wastes. INAP is now moving to further strengthen its global role by networking with regional organisations that are active in the area of ARD, including MEND 3/NEDEM 3 in Canada, the ADTI in the USA and ACMER in Australia. The INAP-Regional Organisation partnership will be formally launched at the 6th ICARD.

Jan 1, 2003

By Nikolaos Polysos, Holger Witthaus

INTRODUCTION The classification system for German coal mining is the result of approximately 100 years of experience in roadway development and longwall mining. It is also based on different research projects covered by national and European research programs. Over the past 30 years, more then 600,000 m of road-ways have been driven and employed for mining activities. To properly describe the German rock mass classification system, therefore, it is useful to take a look at the main geomechanical preferences and common support systems. The decision about the most effective development technique and support system is based on a synthesis of rock mass classification and geomechanical analysis. The properties of surrounding rock, the in situ stress, and the influence of mining activities in several seams at each German mine must be considered for the evaluation of the expected deformation of the roadway. The mine layout, the requirements of ventilation and fire prevention, as well as the need to maintain emergency escape routes for the miners, require that the gate roads remain usable after the passage of the longwall face in most cases. Moreover, the gate roads must be maintained despite the high stresses that are applied during longwall retreat mining. Therefore, gate road design must address a broad spectrum of potential deformation environments. In the past, when gate roads were supported solely with yielding steel arches, lithologic descriptions of the surrounding strata conditions were adequate for the dimensioning of support and the prediction of the roadway deformation. The current conditions of multiple-seam mining at depths of up to 1,700 m require combined support systems, including pattern bolting and backfilled steel arches. Rock bolt support is used for development, after which (typically 50–100 m outby the face) the steel arches are installed and backfilled with building material (concrete) in order to achieve an optimized development rate. The rock mass classification system described below was developed especially for the conditions of German hard-coal mining. It includes the stress distribution caused by multiseam workings (including crossing goaf edges of former longwalls), as well as in situ stresses due to greatdepth and the presence of tectonic faults. It is based on the evaluation of four parameters: • Geotechnical analysis of drill cores • Geotechnical observation of the development face • Geotechnical classification of tectonic structures (faults) • Standard classification derived from geotechnical assessment and evaluation of stress conditions (using numerical modeling for stress calculation) ROCK STRENGTH One of the most important input parameters for describing strata conditions is the strength of the rock. The German classification system is based on a description of lithotypes. This method has been used successfully since the 1950s and is based mainly on the uniaxial compressive strength (UCS) of the material. An evaluation of the rock strength observed in a survey of approximately 82,500 samples of rock core yielded the results shown in Figure 1. The three most common coal measure rock types are mudstone, siltstone, and sandstone. Each shows a specific mean UCS level and a different spread between the minimum and maximum values. Sandstones, in particular, have a wide spectrum of compressive strength, ranging from approximately 40 MPa to greater than 130 MPa, with an average of 85 MPa. The causes of this wide range include different sedimento-logical preconditions, facies, and digenetic processes. [ ]

Jan 5, 2007

By L. H. Banning

This investigation was undertaken to obtain basic information necessary for the design and operation of a plant for recovering metallic values from nickeliferous laterite and serpentine of the Philippine Islands. It was divided into three parts: (1) Mineralogical studies and preliminary mineral dressing tests; (2) electric smelting of the ores, upgrading of ferronickel by blowing with oxygen, smelting laterite slag to produce crude iron, and the production of mild steel; and (3) nickel and cobalt recovery from upgraded ferronickel. Results of the investigation indicate that it should be feasible to recover nickel, iron, and possibly cobalt products from the laterite and ferro-nickel from the serpentine. Mineralogical studies were made on representative fractions of the laterite and serpentine tonnage samples and on five selected samples; mineral dressing tests were made only on laterite. The nickel occurs principally associated with hydrous iron oxides and chemically combined with serpentine; garnierite was the only discrete nickel mineral identified, and it was found in a highly decomposed serpentine. The bulk of the cobalt was found in wadlike manganese oxide material. Approximately twice as much chromite was found in the laterite as in the serpentine, By mineral dressing techniques, laterite was separated into two fractions: one fraction contained over 90 percent of the nickel and cobalt, and 83 percent of the iron; the other fraction contained 74 percent of the chromium. A cobalt concentrate (1.1 percent Co) was produced by a scrubbing and sizing procedure.

Jan 1, 1962

By John R. McWilliams

This report is one of a series published by the Bureau of Mines describing methods and practices at various mines throughout the United States. A previous program, conducted from 1928 to 1939, was well received by the mining industry and technical institutions and provided much source material for engineering textbooks and technical handbooks. The stringent wartime demands on the mining industry, the rapidly changing postwar economic situation, and greatly accelerated technologic growth have combined to render many of the previous data obsolete. The objective of the present program is to assemble reliable technical information on mining methods and practices throughout the country and present it for the use of the mining industry, technical schools, textbook authors, and other interested persons. This report deals with the design and development of the Berkeley open- pit mine at Butte, Mont., owned and operated by The Anaconda Company. The Berkeley pit is but one facet of a well-organized and integrated copper-mining operation involving the entire Butte district. Vein-type mining, important for 75 years, is still in progress at depths from 600 feet to nearly 1 mile; on intermediate levels, low-grade ore left untouched by earlier vein-type mines is being extracted by block caving entire ore zones,3/ and secondarily enriched but lower grade near-surface portions of the same ore zones are being mined by open-pit operations (fig. 1). The Berkeley pit itself is named for the Berkeley mine, one of the old mines that extracted copper ore from high-grade veins in the area that now will be mined by open-pit methods.

Jan 1, 1959

The principal activities of the Bureau of Mines Explosives Research Center during fiscal year 1969 (July 1: 1968, to June 30, 1969) are reviewed in part 1. Part 2 presents short abstracts of the publications issued during this period in the Bureau series and in the outside press. These publications are referenced in part 1 by underlined numbers in parentheses. Other publications, which are not abstracted, are cited in footnotes throughout the paper. ACKNOWLEDGEMENTS The Bureau acknowledges the support received through cooperative agreement in fiscal year 1969 from the Manufacturing Chemists Association. It also acknowledges the sponsorship by the following Government agencies of research conducted during that period: Department of the Air Force, Department of the Army, Department of Health, Education, and Welfare, Department of the Navy, Federal Aviation Administration, National Aeronautics and Space Administration, Space Nuclear Propulsion Office, and United States Coast Guard.

Jan 1, 1970

By F Hancock

A rainfall simulator was developed to assist with hydrogeomorphic research into the stability of engineered landforms associated with rehabilitated uranium mines in the Top End of Australia. It can be used in rough terrain with slope gradients up to 30o. The rainfall simulator is modular, utilises upward jetting nozzles, has a multiple head arrangement and is capable of delivering rainfall intensities between 60 and 300 mmh-1 over areas up to 1000 m2 and could be easily modified for larger areas. Rainfall uniformity is commonly in excess of 80 per cent and the kinetic energy approaches that of natural rainfall (The modular design utilises an equilateral triangular array of rainfall stands, constructed from galvanised steel water pipes and flexible plastic hoses. Total construction costs are low. The water supply reservoir is mobile and easily constructed. An example of its use at Ranger Uranium Mine, investigating the effect of cover on rainsplash and rainwash dominated processes shows that vegetation cover is likely to reduce the erosion rate by these processes by at least four times below that experienced on bare areas.

Jan 1, 1997

By B. J. Barfield

Standard erosion plots (4.6 m by 22.1 m on 9 percent slope) were constructed on the Alston Surface Mine of Peabody Coal Company in Western Kentucky to evaluate the effects of placement technique and density on the erodibility and eroded size distribution from mine spoil and reconstructed topsoil. PLots were constructed with a dozer and scraper pan from shale spoil material, topsoil (A horizon) and subsoil (B and C horizon mixture) using soils stockpiled at the Alston Surface Mine. Plots were evaluated under fallow conditions with a tilled plot surface and two compacted conditions. One compacted condition was generated by tracking the surface with a dozer and rolling with a loaded scraper pan. The second was generated by rolling the surface with a solid wheel compactor. Rainfall was supplied with the Kentucky Rainfall Simulator at a rate of 63.5 mm h-l with the plots in three different soil moisture conditions; dry, field capacity, and very wet. Runoff was evaluated for flow rates, sediment concentrations, and aggregate and primary particle size distributions. Sediment yields and the Universal Soil Loss Equation E130 indexes were calculated from the data for each plot. The erodibility was calculated from the tilled plot data using a weighted soil loss and E130 value from the dry, field capacity and wet runs, and a cover management factor calculated for every other condition. For the topsoil and subsoil plots, sediment yield was greatest for the dozer scraper pan plots and lowest for the tilled plots. For the shale plots, erosion rates from the wheeled compacter plots were the highest and tilled plots the lowest. Average erodibilities were 0.14, 0.38, and 0.41 tons ac h ft-1 tonf-1 in-1 hundred ac-1 for the shale, subsoil, and top-soil plots. Cover management factors for each plot were 1.29, 1.42, and 1.17 for shale, topsoil and subsoil plots compacted with the solid wheeled compacter and 1.29, 3.79, and 2.51 for shale, subsoil, and topsoil plots compacted with the dozer scraper pan conbination. The accuracy of the Wischmeier erodibility nomograph was evaluated on the data collected. Erodibilities were accurately predicted for the topsoil plot and poorly predicted for the sub-soil plot. The accuracy of the CREAMS procedures for predicting the composition (size distribution) of eroded particles was also evaluated. The composition was well predicted for the topsoil plots, moderately well predicted for the shale plots and poorly predicted for the subsoil plots.

Jan 1, 1983

Although the mining industry has achieved record-low fatalities and injuries for each of the last three years, there are still too many miners injured or killed in this nation ís mining operations. Many mining injuries or deaths might have been prevented by using risk assessment to identify and control or eliminate the hazards associated with a task. To focus attention on the importance of conducting risk assessments in keeping mining workplaces safe and healthful, MSHA introduced this initiative on October 12, 2004. This initiative is called SLAM. SLAM is an acronym for Stop, Look, Analyze, and Manage. The steps involved in SLAM are: Stop ñ stop and consider the work involved Look ñ look for and identify the hazards Analyze ñ analyze what needs to be done Manage ñ manage safety by developing and implementing controls Everyone should be aware of the risks of an accident before beginning a task. It may not always be obvious that performing a seemingly routine task could result in an accident. That is why conducting a risk assessment is so important. Itís important to remember that over time a mining workplace seldom remains unchanged. Risks must be assessed whenever procedures or processes change, whenever new tasks are started, or non-routine tasks are performed.

Jan 1, 2005

By Jonathan Peck, Doug Pollitt, Malcolm Scoble

Over the past 5 years the Department of Mining and Metallurgical Engineering, McGill University, has been involved in the performance monitoring of both percussive and rotary drills. Studies conducted in open pit coal and iron ore mines using microprocessor-based research and commercially available instrumentation resulted in the monitoring of at least 6 performance parameters while drilling vertical production blastholes.

Jan 1, 1991

Jan 1, 1994

By Gerald H. Groenewold

Reclamation of surface-mined landscapes is commonly defined only in terms of biological productivity. Other critical concerns associated with surface mining include the long-term quality of groundwater and stability of the postmining landscape. Meaningful reclamation design must address all these concerns. Reconnaissance of postmining landscapes indicates that three types of instability occur in these settings. These include: area-wide settling, localized collapse, and piping. Area-wide settling is most pronounced during the first year after contouring but appears in precontouring valley areas where frozen materials are contoured with a dozer. Although severe in some settings, development typically ends within one year. Piping appears to be a severe and long-term problem in some settings. Piping usually begins soon after contouring ceases and may continue for several years. In some postmining landscapes, piping has only started to develop after as many as five years of apparent stability. Piping is controlled by a combination of physical and chemical conditions in the spoil. A key factor is the presence of highly dispersive materials in the near surface. The design of a stable postmining landscape requires the integration of severe critical factors. These include: 1) detailed knowledge of the distribution of overburden materials with emphasis upon the delineation of highly sodic sediments; 2) proper equipment selection; and 3) a consideration of climatic factors. For reclamation to be successful, it must consider the entire landscape, not merely the soil zone. Any approach short of this will lead, at best, to temporary solutions.

Jan 1, 1980