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1. Domestic Production and Use: In 1983, 12 companies operated 27 primary aluminum reduction plants, with 4 firms accounting for 65% of production. Washington, Oregon, and Montana accounted for 35% of the production; Indiana, Kentucky, Maryland, New York, Ohio, and West Virginia 35%; Tennessee, Alabama, South Carolina, and North Carolina 14%; other central States 16%. Based on published producer prices, output of primary metal in 1983 was valued at over $5.7 billion. Aluminum consumption by 25,000 firms was centered in the East Central United States. Packaging accounted for an estimated 37% of domestic consumption in 1983, transportation 19%, building 17%, electrical 9%, consumer durables 8%, and other uses 10%.

Jan 1, 1984

By J. H. Adkins

The purpose of this research is to identify hazards associated with roof bolting and to make recommendations for procedural and equipment design changes to reduce those hazards. To that end, the project reviewed Literature on related research, collected and analyzed roof bolting injury data, normalized the injury data be exposure time to each activity and identified problem areas within the root bolting tasks. In addition, field data collection forms were prepared and mines selected for field work. In the field, observations were made of eighty (80) different roof bolting crews bolting one hundred fifty-five (155) place;, on forty (40) sections spread among nine (9) mines. Task analysis forms were used to record unsafe behavior or conditions for each crew and each place. Informal discussions were held with the mine's safety and training officer, the maintenance officer, one section foremen and, when possible, the observed crew, concerning the training and experience of the miners. Unsafe acts were categorized and related to the "Activity While Injured" categories developed during the accident analysis. For each of these categories one or more recommendations for corrective measure, machine modification, procedural change or job training were developed. The study produced over fifty (50) specific recommendations involving machine design, procedural, safety training and supervisional issues that would lead to reduced roof bolter injuries in the near term. The authors concluded, however, that only the development of truly hands off/remote bolting can eliminate or reduce to an absolute minimum the hazards to which the roof bolter is subjected.

Jan 1, 1977

By E. E. White

(Cleveland Meeting, October, 1912.) IN, August, 1911, I read a paper before the Lake Superior Mining Institute' on surveying and sampling diamond-drill holes. The present paper gives a more thorough description of these methods, together with a few changes and notes suggested by further experience. Since August, 1911, the methods, used constantly by the Cleveland-Cliffs Iron Co., have been developed to a higher degree of efficiency, and have given great satisfaction. Until a few years ago but little attention was paid to the determination of the actual course of drill-holes, to the accurate sampling and analysis of the material, or to the scientific location of the drill-holes. It has now been common practice for several years in many districts to test the inclination of drill-holes by etching glass tubes with hydrofluoric acid, but the direction of deviation from the vertical has not often been determined. Methods of determining the direction by means of a compass were first developed in connection with drilling in Victoria. The latest method used on the Rand in South Africa has been recently described by John I. Hoffman.2 In the same paper Mr. Hoffman describes an ingenious method of wedging-off a drill-bole so as to start new holes at several successive points. By this means a hole can be deflected in any desired direction, and the curvature can be controlled to a considerable extent, provided the rock is soft enough to permit the hole to be wedged off. Unfortunately, in the Lake Superior district, the jasper iron-formation is so hard that it is very difficult, if not impossible, to do this. I tried to deflect one hole so as to avoid drill-rods stuck in the hole, by using a 1 Proceedings of the Lake Superior Mining Institute, vol. xvi., pp. 100 to 120 (1911). 2 Recent Practice in Diamond-Drilling and Borehole Surveying, Bulletin No. 91, Institution of Mining and Metallurgy (Apr.. 11, 1912).

Nov 1, 1912

By Frank Cook

In this two-year study, an evaluation of mining and reclamation practices at 159 randomly sampled surface coal mines in the United States was conducted. It is concluded that reclamation practices in most of the 22 coal-producing states were adequate during 1975, but that improvement in reclamation performance was desirable in the acid area of the central U. S. and in mountainous southwestern Virginia. Productivity improvements should result from research to determine efficient or optimal operating procedures for dragline stripping of single and multiple seams, surface mining of lignite, multicut and multiseam haulback mining on steep slopes, mountaintop removal, and surface mining in swampy or deeply glaciated areas. Specific candidate research projects are discussed in this report.

Jan 1, 1976

By S. D. Dladla, S. Ramsamy

The majority of the tailings dam operations in South Africa will be required to comply with the new Global Industry Standard on Tailings Management (GISTM) within the next one to three years, depending on the dam classification and the requirements of the respective investors and insurers. With up to 72 auditable requirements, the implementation of the Standard needs careful planning and prioritization. This paper focuses on the practical steps to GISTM compliance for tailings facilities in operation in South Africa. The discussions are based on current practices, South African regulations, and industry standards requirements. The possible changes in dam classifications and the associated requirements are presented.

Jun 2, 2022

By R. G. Zaripova, N. D. Ryan, H. J. McQueen

The austenitic and ferritic stainless steels do not undergo any phase transformation that induces very fine grains in the product through thermomechanical processing as practiced in most other steels. Considerable grain refinement can be achieved by intense multistage deformation descending through warm to cold working; notably multi-axial forging of bulk material can attain high strains with diminished risk of cracking. Hot working to improve ductility yields finer grain sizes as the T is reduced and strain rate E raised; increased strain has limited effect due to the steady state regime. Ferritic steels develop subgrains with size diminishing as E rises and T falls with the advantage of retained strain hardening; recrystallization delivers grains several times the cell size. In austenitic steels, dynamic recrystallization (DRX) provides finer grains at higher E and lower T with a lower limit due to intergranular cracking. The DRX grains contain a strengthening substructure that can easily be retained by quenching; if static recrystallization is allowed to occur the grain size rises markedly. Multistage rolling with diminishing T is able to provide grain refinement to the same degree as straining at the finishing T yet provides better ductility. grains on recrystallization. As a result of the strain induced transformation to martensite, small subzero deformations of austenitic or duplex steels produce very high dislocation densities that yield marked grain refinement when they revert upon reheating.

Jan 1, 2004

By Warren Howes, A. B. Campbell, W. H. Ode

"INTRODUCTION The mines in the eastern part of the now active region of the Tri-State zinc district of Missouri, Kansas, and Oklahoma have unusually acid water, which during periods of moderate or no rainfall is used in the mills to replace losses from evaporation, seepage, and tailings disposal. Its use has caused difficulties by corrosion of equipment and by interference with flotation.The growing importance of flotation, which requires good water, and the increasing troubles caused by the corrosion of the milling equipment have prompted the Mississippi Valley Experiment Station of the United States Bureau of Mines, in cooperation with the Missouri School of Mines and Metallurgy, Rolla, Mo., to investigate the action of the waters on flotation and to undertake to develop means of obviating their harmful effects.The work was under the immediate direction of W. T. Schrenk, consulting chemist, United States Bureau of Mines, and professor of chemistry, Missouri School of Mines and Metallurgy, and Will H. Coghill, supervising engineer of the ore dressing section of the United States Bureau of Mines.ORIGIN OF ACID MINE WATERSRain water, carrying oxygen and carbon dioxide in solution, finds its way into the pores and crevices of the earth's crust and percolates downward through the rocks. This water and its dissolved gases exert a solvent action on many minerals, the extent of which depends upon the nature of the associated minerals.The iron sulphides are the chief sources of the 'trouble with sulphates and sulphuric acid because they oxidize so freely and contain more sulphur than is required to satisfy the iron when ferrous sulphate is formed. Galena and sphalerite may oxidize to sulphates without liberating acid. A few of the common reactions occurring in the Tri-State mine waters may be illustrated by the following equations:"

Mar 1, 1932

By J. W. Thompson

That the governor is hereby authorized to appoint a commission of seven persons, to be known as the industrial accidents commission-two of whom shall be employers of labor, two of whom shall be employees in either mines or industrial establishments of this Commonwealth, or duly accredited representatives thereof, two of whom shall be learned in the law, and one of whom shall be a person skilled and experienced in making investigations-to inquire into the causes and results of industrial accidents in the mines, mills, factories, stores, and upon the railroads, street railways, ships, wharves, and in all industrial establishments, and in all other places where men, women, and children are employed in manual labor in this Commonwealth; to study the most advanced methods for safe-guarding against these accidents; to inquire into the subject of fair compensation for those who are injured in these accidents, and for the families of those who shall be killed as a result thereof; and to study the operation and effect of the Workmen's Compensation Law of 1913. SEC. 2. The chairman of said co~mission shall be designated by the governor, and the person named on said commission as a skilled and experienced investigator shall be the secretary of the commission, The commission shall have power to employ such legal counsel and other officers and employees as it may deem necessary to properly perform its duties. SEC. 3. The secretary of said commission shall receive an annual salary of $2,400 and his actual necessary expenses; and the other members of the commission shall receive no compensation for their services, but shall be allowed their actual traveling and other necessary expenses. The salaries of any other persons employed by the commission shall be fixed by it.

Jan 1, 1920

By Bo Forsman

METAFORA is a simulation model for determination and evaluation of strategies for operating loader/truck systems in mining. A specific version of METAFORA was used to evaluate the haulage system at Solider Mineral's Aitik mine in northern Sweden, one of the largest open pit mines in Europe with a production of about 11.5 Mtpy (about 34000 tpd) of copper are. A production level of 34065 tpd was estimated by simulation runs with METAFORA. Using METAFORA's dispatch rules (Fixed Dispatch, Maximize Trucks, and Maximize Loaders), the truck/shovel system in the Aitik mine was simulated for evaluating alternative dispatch control strategies. The Maximize Trucks rule gave about the same total production (ore + waste) as the Fixed Dispatch rule but a 9% higher ore production. The Maximize Loaders rule gave the lowest production. The marginal truck capacity decreases with increasing number of trucks serving the same loader due to increasing waiting times. In Aitik mine the low crusher capacity results in long dumping times. If the dumping time at the crusher could be halved, the ore production would increase by 14%. The paper indicates that the use of software like METAFORA can result in a substantial reduction of time, effort and cost in shovel/truck system design and evaluation.

Jan 1, 1992

By Gordon M. Miner

When I was originally invited to speak to this audience on the subject of the future supply of precious metals I was somewhat apprehensive and suggested that the Program Chairman select someone with more credentials. He declined and the results of our conversation gave me cause to reflect and recall the opportunities I have had over the years and how fortunate I have been to be associated with so many successful companies and knowledgeable people affiliated with the precious metals field. I discovered that since 1935, 1 have worked in or visited most of the gold and silver camps in the United States; have been a leaser of a gold mine in Mohave, California; have both lost and made money in the silver futures market; have worked for two of the greatest precious metals companies in the United States - Homestake Mining Company and Hecla Mining Company, have spent a considerable amount of time in precious metal related discussions with men like Don MacLaughlin, Paul Henshaw, Dick Stoehr, Abe Shoemaker, Bill Love, Phil Lindstrom, Simon Strauss, Herbert and Bunker Hunt and many others. It is those exposures and experiences that I draw onto discuss the subject at hand.

Jan 1, 1980

By Nicholas P. Callas

This report presents research results obtained in the investigation of deviation control of boreholes in the rotary drilling process. The approach taken in this research is the passive method of placing stabilizers in the bottom-hole assembly to control deviation. Extensive use was made of the drill string mechanics theories of Lubinski and Woods. Analog, digital and hybrid solutions to variety of boundary value problems were investigated in order to determine the best models for bottom-hole assemblies. Field drilling data was analyzed and the results obtained from various models were compared to the actual drilling results. Various accomplishments of this work have been published in open energy industry literature, with more publications to follow.

Jan 1, 1981

By J. A. Ober

"In 2015, the estimated value of nonfuel mineral production in the United States decreased by 3 percent from that in 2014 (Table 1), mainly as a result of decreased metal and metallic mineral prices, especially iron ore, copper and precious metals. Lower metal prices were attributed to decreased consumption, especially in China and increased global inventories. Several U.S. metal mines were idled in 2015, including the only U.S. rare earths mine at Mountain Pass, CA. Downstream processors also were affected, with smelters and refiners either shutting down or idling production lines. Increases, however, took place in the value and quantity of production of industrial minerals, especially those used in the construction sector, including cement, construction sand and gravel and crushed stone. Trends in mineral-related sectors of the domestic economy, except for iron and steel manufacturing, aluminum manufacturing, coal mining and metals mining, all experienced growth (Table 2).Discussion of mine production is frequently segmented according to the type of materials produced within the broad categories of metals and industrial minerals (also known as nonmetallic minerals). Industrial minerals can be further subdivided as construction aggregates and other industrial minerals. Metals tend to have higher unit values but very low production quantities compared with those of industrial minerals, which have higher production quantities but are lower-valued materials, such as crushed stone or construction sand and gravel. Therefore, for discussion and analysis of the performance of the nonfuel minerals industry, the value of production is used rather than the tonnage produced. Tonnages of construction aggregates are orders of magnitude larger than those for most other mineral commodities thus making direct comparisons based on weight meaningless (Fig. 1).Mineral industry performanceThe estimated value of domestic nonfuel mineral production, including metals ($26.6 billion) and industrial minerals ($51.7 billion), in 2015 declined to a total of $78.3 billion, from $80.8 billion in 2014 (Table 1). However, as shown in Fig. 2, minerals remained fundamental to the United States economy, contributing to the real gross domestic product at several levels, including mining, processing and manufacturing finished products. Net exports of mineral raw materials and old scrap were $14.4 billion. Domestic raw materials, along with domestically recycled materials, were used to produce mineral materials worth $630 billion. These mineral materials, including aluminum, brick, copper, fertilizers and steel, and net imports of processed materials (worth about $32 billion) were, in turn, consumed by downstream industries with a value added to the gross domestic product estimated to be $2,490 billion."

May 1, 2016

By Grant R. Brown

This report presents the results of a study examining the relationship between supervisor characteristics and performance in underground coal mines, The specific objectives of the research include; document tasks performed by first-line supervisors during a normal shift; explain why supervisors carry out their duties as they do: identify salient characteristics of effective first-line supervisors; and formulate criteria for selecting and developing candidate supervisors. To accomplish the study objectives, on-site observation and data collection was carried out at 13 underground mines in Illinois, Ohio, and Pennsylvania. One hundred thirty-eight first-line supervisors were observed during a full work-shift and discussions with the supervisors and the mine superintendent were held during the course of the visit. The observational data from the study provide a detailed description of what supervisors to during their shift. The report begins with an introduction discussing the problem being studied and objectives of the research. The literature related to supervisor selection is then reviewed. The following section describes the research design including data collection procedures and statistical methodology used in the study. The next sections present the analysis of mine, section, crew, and supervisor characteristics. The report concludes with a discussion of the results of the study and recommendations concerning supervisor selection and development.

Jan 1, 1987

By William W. Adams

Reports for the calendar year 1923 that have been transmitted to the Bureau of Mines of the Department of the Interior by mine officials of the various coal-producing States show that accidents in and around the coal mines resulted in the death of 2,452 men. The output of coal during the year, as reported to the United States Geo- logical Survey, was 641,476,000 tons; hence the fatality rate per million tons was 3.82 as compared with 4.15 for 1922, a decline of about 8 per cent. The average rate for the decade ending with 1922 was 4.11. This reduction of 8 per cent in the fatal-accident rate per million tons is equivalent to the saving of 210 lives--that is, had the fatality rate of 1922 continued through 1923 the number of lives lost would have been 210 more than they actually were. Not only was there a net reduction in the fatality rate from all causes combined, but each of the main causes of coal-mine fatalities also showed a decline. Falls of roof and coal, which generally account for nearly half of all deaths in coal mines, were responsible for 1,158 fatalities in 1923, which represents a rate of 1.81 per million tons as compared with 1.90 in 1922. (See Table 2.) Haulage accidents underground usually cause about 17 per cent of all fatalities, and the reports for 1923 show that 413 deaths were due to this cause, indi- cating a rate of 0.64 per million tons, as against 0.71 for the previous year. Gas and dust explosions killed 372 men, the fatality rate being 0.58; the rate for 1922 was 0.65. Seventy-five deaths were due to electricity, for which class of accidents the fatality rate per million tons was 0.12 as compared with 0.16 the year before. Powder and other explosives caused 114 deaths, representing a rate of 0.18 as compared with 0.19 for 1922. Of the 2,452 fatal accidents during the year, 2,249 occurred under- ground, 46 in shafts, and 157 on the surface. At bituminous coal mines the number of deaths was 1,943, of which 1,816 were under- ground, 31 in shafts, and 96 on the surface. At the anthracite mines

Jan 1, 1923

By N. Akbulut, A. Anani

From the initial planning phases to the closing of a mine, mining is an industry where high attention, care, and sensitivity are needed in every step of the mine life. Since mining projects have a long-life span, exceeding a decade sometimes, managing a whole mine project is challenging, especially when challenges faced due to generational differences are considered, such as tracking and logging data, or the usage of different engineering solutions change over time. Along with the overall hardship caused by the time put into a mining project, the present-time operations are very costly where each minute counts. In present-time operations, every decision made, and every minute used during planning and operations has an impact on the efficiency, safety, and economics of the project. Having extremely harsh conditions in both the excavation and mineral processing operations not only slows down the processes but creates very dangerous environments that need to be handled with precise safety measurements. To support the already established processes, we could implement new technologies and use them to our advantage. Virtual reality (VR) is one of these technologies that we could implement in the mining industry. VR is a technology that emerged in the 1960s creating virtual environments and platforms. The user experiences these virtual environments from head- mounted headsets to rooms with 360 screens, all with different levels of immersion. These higher levels of immersion, create a higher level of presencemaking the users more engaged in the activity they are trying to accomplish. These two factors of immersion and presence are what make VR unique and beneficial. VR has some applications and case studies in the industry along with some research being conducted in universities. Unfortunately, there has not been a comprehensive literature review or analysis regarding only VR and its implementations for the mining industry in the last 5 years. This paper aims to describe what VR is and its relation to the mining industry, in the most recent years. The paper first gives a brief background on what VR is and its key concepts. Secondly, it will give information on how the initial stages of the literature review were conducted and the findings along with discussions. The paper will finish with the conclusion drawn from the discussion and potential future work.

Feb 1, 2023

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

Coagulation-Neutralisation Technology to Treat Wastewater from Lead-Zinc Concentrator

Sep 13, 2010

By Yi Luo

Bolting the mine roof is one of the noisiest underground mining operations. The main contribution to the noise is the drilling of the roof bolt holes, especially drilling in hard rock. Previous research shows that the specific energy consumed in drilling bolt holes is inversely proportional to the bite depth (i.e., penetration per drill revolution). Less specific energy at a reasonably high bite depth means less energy is wasted in the drilling process for producing heat, bit wear and noise. Therefore, proper control of the drilling operation to achieve a reasonably higher bite depth can reduce drilling noise from its sources as a proactive noise control approach. In order to explore the feasibility and develop the proactive technology for reducing drilling noise, drilling tests have been conducted in laboratory settings. The preliminary results show that significant reduction in noise dose can be achieved by drilling in medium hard rock with uniaxial compressive strength of about 276 bars (4,000 psi) and at a reasonably high bite depth of about 4.6 mm/rev (0.18 in./rev). This paper presents the findings from laboratory experimental studies.

By M. H. Attia

The concept of sustainable development has been evolved into a working framework for sustainable manufacturing, in which the environmental requirements are introduced into product development at the design stage. This keynote paper is discussing a number of issues pertaining to the impact of manufacturing on the environment. The conflicting requirements of sustainable development, sustainable manufacturing (SM) and economical growth are presented in the light of successful case studies that were able to convert conflicts into opportunities. Integration of SM into the product life cycle is also presented. A number of concepts that are related to Ecoefficiency, e.g., inverse manufacturing, demanufacturing and re-manufacturing are also discussed. The paper underlines the fact that the positive impact of this new philosophy is equally applicable and beneficial to both; developed and developing countries. The paper concludes with an overview of Global trends in environmentally benign manufacturing (EBM); e.g., product-take back and emerging material and processing technologies. The state-of-the-art approach to Life Cycle Impact Assessment and integration of design for the environment DfE principles are demonstrated through some case study.

Jan 1, 2006

Arsenic.--Inorganic arsenic has been added to the Environmental Protection Agency's list of hazardous air pollutants because of a high probability it can cause cancer. EPA estimates that inorganic arsenic emissions into ambient air total more than 6,000 tons per year, with about 65;L of this coming from the operations of copper, lead, and zinc smelters. Asbestos Detection.--In June 14, the President signed S. 1658 providing $172.5 million to detect and remove asbestos hazards in schools. Asbestos Use Must be Reported.--All firms using asbestos in the manufacture of some 30 categories of products must describe in detail how they use the mineral to the Consumer Product Safety Commission, for all manufactures since January 1, 1977.

Jan 1, 1980