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By W. A. Dunkley, W. W. Odell

About two-thirds of the manufactured gas supplied to the public by the gas plants in the Illinois district is cnrbureted water gas. The leading generator fuel is coke, ma.de in by-product c.oke ovens or in retorts, chiefly from eastern gas coals. During the fall and winter of 1917-18, when the demand for coke by war industries and the restrictions of the Fuel Administration in connection with the transportation of coke from eastern States made it almost impossible for many gas companies to obtain their coke requireml'nts, several water-gas plants had to use bituminous coal as generator fud. Many operating difficulties were encountered, some of which were solved more or less satisfactorily in different plants. A number of plants attacked the problem rather blindly because facilities for making tests were lacking and because technical men were too busy with labor and supply problems to study thoroughly the conditions involved or to ascertain what other plants had done with this fuel. It was therefore with the hope of assisting the gas industry during this critical period, and of promoting the use of Central District coals for gas making, that the Illinois Mining Investigations, a joint agency of the U. S. Bureau of Mines, the University of Illinois, and the Illinois Geological Survey Division undertook the, tests discussed in this paper. • This report was compiled under the auspices of a technical committee appointed by Gov. Frank 0. Lowden to promote the use of Central District coals in gas manufacture as a war measure. This committee included the following representatives of the various agencies concerned: U. S. Bureau of Mines, E. A. Holbrook and W. W. Odell; Illinois Gas Association, C. W. Bradley and R. B. Harper; University of Illinois, Dean C. R. Richards, Prof. S. W. Parr, and Prof. H. H. Stoek; State Geological Survey Division, F. W. De Wolf, G. H. Cady, a.nd W. A. Dunkley. F. W. De Wolf was chairxnan of the committee and E. A. Holbrook was secretary.

Jan 1, 1924

By Scott Turner

The monetary metals , gold and silver , have recently been the object of such general interest that the United States Bureau of Mines has received many inquiries regarding them . Though requests for technologic information have been numerous , they have been exceeded in number by those concerned with economic aspects of these metals . The nature of the latter communications indicates that the public is not generally aware that various Bureau publications are available which deal with the economic situation of gold and silver . For this reason , it is deemed advisable to present a brief résumé of the papers which are obtainable from the Bureau or the Superintendent of Documents , together with the text of three articles recently prepared by the Director , reprints of which are not otherwise available . The Bureau of Mines compiles figures showing mine production of gold and silver , by districts and States , and cooperates with the Bureau of the Mint in determining the total annual output in the United States as a whole . 3 It recently established an annual canvass to determine the consumption of silver in the arts and industries of the United States , and published an economic paper covering such use in 1928 and 1929 , followed by an information circular on silver consumption by industry during the 2 years subsequent . A 4-year record is thus provided for those interested in utilization of silver . The Bureau has also published summarizations of all available data upon world production since 1493 of gold and of silver . It has , furthermore , rendered available a compilation of production- data of silver mines of the world , and an analysis of it , showing the proportions of silver and other metals contained in all the ores from which silver is derived . " All of these papers are concerned solely with putting into readily usable form statistical data and other factual material ; they do not offer theories or express opinions upon controversial questions related to these metals . Three other recent papers concerned with gold and silver are presented below in order to put them in shape for distribution by the United States Bureau of Mines . All three of them are by the Director of the Bureau . It should be noted that these papers do not commit

Jul 1, 1933

By D. K. MACKAY

The production of oil and gas in Arkansas is confined to two distinct and widely separated regions of the state; namely: (1) South Arkansas in the Gulf coastal plain, where 49 fields-many containing two or more reservoirs or pools-yield oil, condensate and gas from beds in the Cretaceous and Jurassic, and (2) Northwest Arkansas, a part of the Arkansas Valley, where only dry gas is produced in 21 fields from sandstones of Pennsylvanian age. Exploration during the year 1945 centered largely in these two producing regions, but some of the geophysical surveys were made and wildcat drilling was done a considerable distance outside these regions.

Jan 1, 1946

By R. Heiser, J. Vendetti, B. P. Connor, E. J. Haas

"DISCLAIMER The findings and conclusions in this paper are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health. Reference to specific brand names does not imply endorsement by the National Institute for Occupational Safety and Health. ABSTRACT Health and safety indicators help mine sites predict the likelihood of an event, advance initiatives to control risks, and track progress. Although useful to encourage organizations to work together, executing such risk assessments comes with challenges. This paper focuses on one trona mine’s experience in the development and implementation of a field level risk assessment program to help its entire organization understand and manage risk to an acceptable level. Through a transformational process of ongoing support and communication, Solvay Green River fostered a culture of trust and safety grounded in risk assessment, safety interactions, and hazard correction. The application of consistent risk assessment (RA) tools was critical to create a participatory workforce that not only talks about safety, but actively identifies energies that contribute to hazards and potential incidents. In this paper, reflecting on the mine’s process of RA implementation provides examples of likely barriers that sites may encounter when trying to document and manage risks. As discussed, consistent efforts to establish a participatory risk management program are worth the initial struggle to ultimately reduce incidents. INTRODUCTION Work-related health and safety (H&S) incidents often account for lost days on the job, contributing to organizational/financial and personal/social burdens [1-2]. Accompanying research demonstrates that risk and ambiguity around risk contribute to almost every decision that individuals make throughout the day [3-4]. In response, understanding individual attitudes toward risk has been unquestionably linked to predicting H&S behavior [5]. Although an obvious need exists to identify more comprehensive methods to assess and mitigate potential hazards, some argue that risk management is not given adequate attention in occupational H&S [6]. Additionally, research suggests that a current lack of knowledge, skills, and motivation are primary barriers to mitigating workplace risks [3-6]. Therefore, enhancing knowledge and awareness around risk-based decisions, including individuals’ abilities to understand, measure, and assign levels of risk to determine an appropriate response, is increasingly important in hazardous environments to predict and prevent incidents. This paper focuses on tailored approaches to field level risk assessment (FLRA), measurement, and common barriers to participating in such activities. The authors use a trona mine in Green River, Wyoming, as a case study to illustrate how the organization overcame widespread and site-specific challenges to implement a proactive risk management program. By discussing the mine’s tailored FLRA program, this case study contributes to the literature by first, providing examples of critical components that need to be in place to ensure successful risk management and second, context for continuous quality improvement that can foster a higher level of trust and empowerment on site."

Jan 1, 2017

By R. Heiser, J. Vendetti, B. P. Connor, E. J. Haas

Health and safety indicators help mine sites predict the likelihood of an event, advance initiatives to control risks, and track progress. Although useful to encourage individuals within the mining companies to work together to identify such indicators, executing risk assessments comes with challenges. Specifically, varying or inaccurate perceptions of risk, in addition to trust and buy-in of a risk management system, contribute to inconsistent levels of participation in risk programs. This paper focuses on one trona mine’s experience in the development and implementation of a field-level risk assessment program to help its organization understand and manage risk to an acceptable level. Through a transformational process of ongoing leadership development, support and communication, Solvay Green River fostered a culture grounded in risk assessment, safety interactions and hazard correction. The application of consistent risk assessment tools was critical to create a participatory workforce that not only talks about safety but actively identifies factors that contribute to hazards and potential incidents. In this paper, reflecting on the mine’s previous process of risk-assessment implementation provides examples of likely barriers that sites may encounter when trying to document and manage risks, as well as a variety of mini case examples that showcase how the organization worked through these barriers to facilitate the identification of leading indicators to ultimately reduce incidents.

Jan 1, 2018

By R. Heiser, J. Vendetti, B. P. Connor, E. J. Haas

Health and safety indicators help mine sites predict the likelihood of an event, advance initiatives to control risks, and track progress. Although useful to encourage individuals within the mining companies to work together to identify such indicators, executing risk assessments comes with challenges. Specifically, varying or inaccurate perceptions of risk, in addition to trust and buy-in of a risk management system, contribute to inconsistent levels of participation in risk programs. This paper focuses on one trona mine’s experience in the development and implementation of a field-level risk assessment program to help its organization understand and manage risk to an acceptable level. Through a transformational process of ongoing leadership development, support and communication, Solvay Green River fostered a culture grounded in risk assessment, safety interactions and hazard correction. The application of consistent risk assessment tools was critical to create a participatory workforce that not only talks about safety but actively identifies factors that contribute to hazards and potential incidents. In this paper, reflecting on the mine’s previous process of risk-assessment implementation provides examples of likely barriers that sites may encounter when trying to document and manage risks, as well as a variety of mini case examples that showcase how the organization worked through these barriers to facilitate the identification of leading indicators to ultimately reduce incidents.

Jan 1, 2017

By N. R. Paterson, D. G. MacKay

"The geology of the Mattagami mining camp, while of particular economic significance, is unfortunately obscured by a very thick mantle of overburden. For this reason geo-physical methods have been relied upon heavily in exploring the area. Geophysical data over five important sulphide discoveries show how targets are selected for drilling and how effective geophysics has been in assisting subsequent development programs."

Jan 1, 1960

By Frederick Felder

The paper point out the Angostura deposit is located in Colombia. The Angostura deposit, located within the Eastern Cordillera of Colombia is hosted by Triassic-Jurassic quartz monzonite and quartz diorite porphyries emplaced into Precambrian gneisses of the Bucaramanga Group. Silicification, pyritization, sericitization, alunite and pyrophyllite and other alteration and indicator minerals suggest a high sulfidation origin for the strong hydrothermal alteration. Major faults and shear zones occur in the area with NE, E-NE, E-W, WNW, NW and N-S directions. Analysis of geological results and structural modeling has also demonstrated that there is potential for additional high-grade ore shoots within the presently known mineralized structures. Delineating these structures should result in an increase of overall grade and contained ounces.

Apr 22, 2003

By W. Dan Walker

In recent years the Federal Bureau of Mines tested and approved four new types of self-contained breathing apparatus and a facepiece designed for use with the McCaa 2-hour self-contained oxygen breathing apparatus. The Bureau also developed and perfected a battery-powered lifeline telephone for use in mine rescue and recovery operations. Some of this equipment is described in Bureau of Mines Information Circular 7413.4/ This publication is a revision of information Circular 7413 and presents pertinent information on more recently developed mine rescue equipment. The breathing apparatus described herein are 1/2- and 3/4-hour sell-contained types of much simpler design than the conventional 2-hour self-contained oxygen breathing apparatus ordinarily used by mine rescue crews; however, it is just as important to select rescue crews carefully and to train them properly in the use, care, and limitations of the newer types of apparatus as well as the older, established types, if the newer types are to be used safely. The Bureau of Mines recommends that 1/2- and 3/4-hour self-contained breathing apparatus be used only as auxiliary equipment in mine rescue and recovery work and that the capabilities and limitations of the apparatus should be well understood by those who wear the equipment.

Jan 1, 1957

By J. G. George

A brief review of the silver industry is presented to set the stage for the analysis of the distribution of silver production by source from various types of mines in Canada and of the changing relationship between the total output of silver and the total output of base metals. The decline in the average grade of the Canadian mines is also discussed and a trend for the future is proposed. The report then examines in broader aspects the world primary silver production and concludes, in the section on outlook, that the effective supply in primary silver will grow at a rate significantly lower than the growth rate expected for base metals. A cumulative deficit of some 900 million ounces is projected for the period 1975-1980 and a further deficit of some 1,100 million ounces if projected for the 1980-to-1985 period.

Jan 1, 1977

By R. A. Meister

The study on improving surface coat refuse disposal site inspections included surface inspections of 15 refuse disposal sites. Monthly aerial photos were taken of the sites and computer methods were used to determine elevation changes. Photogrammetric techniques that were used are described in detail. A comparison of the results of each of these inspection techniques is included. A detailed evaluation of the photogrammetric techniques was made and conclusions were drawn concerning the advantages and disadvantages of using aerial photography and photogrammetry as part of the inspection procedure. Operators' opinions of the aerial photography methods are included.

Jan 1, 1980

By T. Hadley, E. Catovic

"Northern Minerals Limited’s (ASX: NTU) flagship project is the Browns Range Rare Earth Project (the Project) located in Western Australia, consisting of a number of deposits with high value, heavy rare earth elements, in particular yttrium, terbium, and dysprosium. The deposits are dominated by xenotime mineralisation, which occurs within hydrothermal silicified and hematitic breccias. The Company delivered an initial JORC compliant resource estimate for the Project at the end of 2012 of 10,500 t of contained total rare earth oxides (TREO), which was increased to 28,084t of contained TREO in October 2013 and further enlarged to 47,997 t of contained TREO in February 2014. Concurrent with the growth of the Project resource base, significant progress has been made in developing the metallurgical process for the beneficiation and extraction of rare earth elements (REE’s) from the xenotime mineralisation. Development of the beneficiation circuit evaluated several process options and selected whole-ore flotation and magnetic separation, followed by flotation (hybrid circuit) as the two preferred flowsheets to pilot, following encouraging results on the bench of 83% and 86% recovery to a 20% TREO mineral concentrate respectively. Several downstream hydrometallurgical extraction flowsheets were evaluated. However, the following two preferred process flowsheets were ultimately selected for further detailed investigation during the prefeasibility study: 1. Sulphation bake, water leach, purification, oxalate precipitation, and/or calcination to produce a mixed RE oxide; 2. Sulphation bake, water leach, phosphate precipitation, caustic conversion, HCl leach, and oxalate precipitation to produce a mixed RE oxalate. Excellent heavy rare earth oxide (HREO) extractions (~ 90%) from beneficiation concentrates were achieved on the bench for both circuits, however flowsheet 1 was ultimately selected as the preferred flowsheet to pilot due to lower capital and operating cost. A mixed rare earth oxalate (42% TREO) or oxide (92% TREO) can be produced with low levels of Th and U of 3 ppm and 6 ppm respectively."

Jan 1, 2014

By Alexander Siefert, Steffen Pankoke

In the development of commercial vehicles as well as of passenger cars, the effects of vehicle vibrations on operating safety, health and comfort can only be predicted by numerical simulation when appropriate occupant models are available. Such models must be based on human anatomy and have dynamic properties of real humans in order to achieve realistic results. Since human dynamic behavior depend on posture and percentile, the occupant model needs to be adjustable to these parameters with respect to geometry and dynamic properties [1,2]. Dynamic Human Finite-Element-Model CASIMIR CASIMIR is a non-linear, dynamic finite-element-model of the human body. It consists of a dynamic model of the upper torso with head, neck, shoulders and arms as well as of a dynamic model of the lower extremity with pelvis and legs. The most important part is the lumbar area with dynamic non-linear models of the lumbar spine and of back and abdominal musculature. The frequency-dependent characteristics of the intervertebral discs and the effects of muscle activation and non-linear frequency-dependent muscle properties are included. In the latest stage of development, CASIMIR has been equipped with a compliant model of the body surface in the contact areas to the seat. This results in a very realistic transmission of static and vibrational forces into the human body, see fig. 1. Intense model verification and validation has been performed in all stages of model development, starting with validation of small components like intervertebral disc, ending with validation of whole-body-vibrations using measurements of the dynamic mass / mechanical impedance [4]. For an in-detail examination of stresses in the vertebral bodies and discs, a non-linear submodel of the lumbar spine with an increased number of degrees of freedom can be coupled to the whole-body-model, enabling the researcher to examine local effects of vibrations and single shocks on the lumbar materials. [ ] Since it is well known that human dynamic behavior is significantly affected by anthropometric data and posture, CASIMIR can be individualized to the anthropometric status of single individuals or to the mean values for specific percentile groups. Furthermore, posture can be adjusted to the seating conditions applicable to a specific vehicle. Posture modification capabilities include the variation of the lumbar lordosis [3].

Jan 6, 2006

By Joe Zhou

"Mineralogical characterization and metallurgical extraction of silver is challenging due to its complex mineralogy and chemistry. Over 200 Ag-bearing minerals have been identified and a silver-rich ore body would typically contain 5 to 10 different silver minerals. Silver can occur not only as discrete microscopic (visible) silver minerals but also as submicroscopic (invisible) silver in other minerals. During processing, silver may form passivation compounds such as silver hydroxide, silver sulphide, jarosite-like silver sulphate, silver halide or silver cyanide precipitate, all of which may negatively impact on silver extraction. Knowing the deportment of silver in the ore and its metallurgical products is important in flowsheet design and plant optimization. This paper begins with the classification of silver ores and minerals and a review of processing techniques, and focuses on the major mineralogical factors to explain why and how these factors affect silver extraction. Case studies are provided to demonstrate the application of silver process mineralogy in flowsheet design and plant optimization.INTRODUCTIONSilver was known to and utilized by mankind since ancient time. Actually, it was one of the earliest metals discovered and utilized by mankind after gold and copper.Silver is the whitest metallic element. It is rare, strong, corrosion resistant, and unaffected by moisture, vegetable acids, or alkalis. Silver is also resonant, moldable, malleable, and possesses the highest thermal and electric conductivity of any substance. The chemical symbol for silver is Ag, from the Latin argentum, which means white and shining. Although silver does not react with many chemicals, it does react with sulfur, which is always present in air at trace amounts. The reaction causes silver to tarnish, and consequently it must be polished periodically to retain its luster.Silver possesses many special physical characteristics and qualities that make it useful to a variety of industries. The photography industry is the biggest user of silver compounds. Silver forms the most light-sensitive halide salts, which are essential to developing highquality photographic prints. Silver also has the highest electrical conductivity per unit volume of any metal, including copper, so it is used extensively in electronics."

Jan 1, 2010

By William J. Douglas

This document describes the development of a conventional mining equipment data base, and an approach for conducting industrial engineering studies of arbitrary mining systems employing network techniques. Data was acquired through underground time studies. Each member of a four-man field team was assigned to a specific machine during each shift for which observations were conducted. Using digital wrist watches and networks describing the man-machine interactions, all events occurring luring the course of each shift were recorded on cassette tapes. The tapes were transcribed, coded, keypunched, and validated using computerized editing techniques. The resulting data files were processed to provide statistics relating to activity durations and event frequencies. The results were used to evaluate operator, machine, and system performance for each section which was observed. Equipment, reliability, and maintainability analyses were conducted using the industrial engineering data files in conjunction with historical information collected at the mine site.

Jan 1, 1976

By John H. Weigand, Stephen V. Crum

"VIBRONICS, INC. instrumented and monitored a residential structure for response to,blasting at aMidwestern surface coal operation. The residence was owned by the mining company and was extremely close to the operation. Blasting was conducted within 120 feet (36.5 meters) of the test structure. Up to seventeen (17), four (4)-channel seismographs were used during the monitoring period. The basement walls and floor were monitored. VIBRONICS, INC. also monitored a brick chimney in the basement and attic. Structural responses were then compared to outside vibration measurements taken in the soil near the foundation."

Jan 1, 1998

By R Cunningham

The E26 Lift 1 North Project took 37 months from the approval on 1st January 2019 to the commencement of production on 1st March 2022. This was five months ahead of the feasibility plan. When compared to the previous E48 Block Cave construction 12 years prior, which was of a similar size and design with ten extraction drives, crusher and conveyors, the E26 Lift 1 North project has been delivered at 29 per cent less capital cost. Key metrics achieved by the project include 12.7 km of development, 240 km of production drilling for drawbells and undercut blasting, 107 drawbells fired ready for production as well as only three Lost Time Injuries compared to 16 during E48 construction. The Lift 1 North Project Team has established a significant point of difference with the delivery being completed by the ‘Owners Team Model’ not Lump Sum or Turn-key. E26 Lift 1 North is now supplying the Northparkes processing plant for the next eight years. This paper discusses major milestones achieved throughout the process, modifications to processes from previous block cave construction at Northparkes as well as novel approaches to work to achieve the successful delivery of the project.

Mar 29, 2023

[CONTENTS COUNTY NO. OF MINES MINE INDEX PAGE]

Jan 1, 1980

By R. E. Morgan, D. L. Douglass

The determination of phase relationships and solid-solubility limits can be performed by quantitative metallography in addition to the usual X-ray and metallographic techniques. For example, Beck and smith1 redetermined the ß/ß + ?, ß + ?/?, a/a + ß and a + ß/ß boundaries in the Cu-Zn system by measuring the volume fraction of second phase of several alloys and extrapolating the volume fraction-composition curves to 0 and 100 pct. A modification of this technique is suggested for certain alloy systems, in which it is not necessary to use several alloy compositions but merely one. A single two-phase alloy may be used to determine terminal solubilities in the following manner. The method consists of equilibrating samples of the alloy in a two-phase region adjacent to the desired solid solution, at three or more temperatures, quenching, measuring the volume fraction of second phase present, and applying an analytical treatment to calculate the unknown solid solution. However, two restrictions are inherent in this technique. They are: 1) only certain types of alloy systems are amenable to it, and 2) the general features of the system must be known. The first drawback to the new technique, i.e., that only certain types of systems may be studied, necessitates that the composition at one end of the tieline must either be constant with temperature or well established as a function of temperature. Either a pure metal or some intermetallic compounds fulfill the former. If it is assumed that the volume per gram-atom of a dilute solution is unchanged by the addition of element B to element A, the composition of the solid solution in equilibrium with the second phase may be determined by a material balance and is given by where X, = volume fraction of B in a solid solution Xc = volume fraction of B in compound c X = volume fraction of B in alloy f = volume fraction of second phase The composition by weight may then be determined by the use of tables in the Metals Handbook2 when the density ratio of the solid solution constituents is known. A possible alternative treatment involving the use of the lever rule is less precise than the above tech- nique. This may be used when the density of the solid solution is either known or may be calculated from X-ray data for several compositions. The following analysis is then made. The ratio of compound to solid solution (by weight) may be expressed as follows: x0 - x wc = xr-x = x0 - x r2i Xc -X where Wc = weight of compound w = weight of solid solution x, - alloy composition, weight percent x = unknown composition Xe = compound composition but where V, = volume of compound VA = volume of solid solution pc = density of compound p, = density of solid solution fc = volume fraction of compound fB = volume fraction of solid solution and fs = l -fc then If pc and xc are known, and f, is measured, then pB is the only unknown on the right side of Eq. [4]. The known densities of the solid solution can be plotted for various compositions and can then be expressed mathematically as a function of composition. The use of an expression of pB = f(x)reduces the equation to one unknown—the desired solubility. In the event that the densities are unknown, they may be calculated for various compositions from Vegard&apos;s law. The calculated values are then plotted and expressed analytically. The most accurate results are obtained for Eq. [4] when fc<< 1, i.c., when (x, -x,) - 0, &/l-f, - m; but as fc/l -fc - 0, (xl-x,)- (x, - x), and x - x,,. However, the accuracy with which fc can be measured decreases as f, decreases.3 Alloys for investigation must be selected by a compromise, which is based upon an error analysis of Eq. [4] and knowledge of the accuracy of volume fraction measurements. An examination of phase diagrams in the literature showed many which were amenable to the technique described here. The zirconium-copper system was selected in order to determine the solubility of copper in beta zirconium. Pieces of an alloy which was arc-melted three times were wrapped in tantalum foil and sealed under an argon atmosphere in Vycor tubes. The sealed samples were equilibrated at temperatures from 850" to 960°C for 3 weeks and quenched to room temperature by smashing the capsule in water. Several planes of polish were examined, and

Jan 1, 1960

General economic conditions continued to improve in the second quarter of 1984 as real gross national product advanced at an annual rate of 7.5 percent (table 1). This followed an even larger first quarter annual rate increase of 10.1 percent. The slower second quarter growth was greeted as a sign that the economy is not over-heating. The signs of slowed growth in some sectors suggest that the recovery may continue well into 1985 without the inflation symptomatic of a rapid recovery. Most of the slowdown in growth was absorbed by business inventories, personal consumption of durable goods, and residential fixed investment. Business inventories grew by only 68 percent as much as in the first quarter, personal consumption for durable goods grew by 58 percent of the first quarter rate, and residential fixed investment slowed to only 44 percent of the first quarter growth. Sectors with accelerated growth in the second quarter included personal consumption of nondurable goods and of services, which increased at annual rates of 9.6 percent and 3.8 percent, respectively, and Federal purchases of goods and services, which increased at an annual rate of 47.9 percent.

Jan 1, 1984