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By E. A. Zawadzki

The problem of pollution of water by mine drainage is at least as old as the mining industry itself. However, research on the formation, composition, treatment, and abatement of mine water is a relatively recent historical event. At Bituminous Coal Research, Inc., acid mine drainage control has been an important area of work since 1944, at which time BCR began sponsorship of research at West Virginia University. The work at West Virginia University involved a detailed study of the acid mine drainage problem and led to the identification of iron oxidizing bacteria as important factors in the formation of acid mine water. The results of this research were summarized in 1954 by Temple and Koehler (1) who concluded that "no practical solution for the problem" of controlling acid mine drainage is yet known.?

Jan 1, 1967

By L. Frost

"Since the late 1990s, increased prevalence of severe lung disease among US coal miners has been observed, particularly in central Appalachia where thin-seam mining is prevalent. While respirable silica exposures have been implicated in many cases, the available dust monitoring data from mines shows no explanatory trends. One possible factor could be differences in the relative toxicity of silica particles based on their surface condition. Previous research has indicated that particles with occluded surfaces (e.g., by a thin layer of clay) may be less toxic than those with non-occluded surfaces. However, this dust characteristic has not been investigated before now in central Appalachian mines. In the present study, 18 respirable dust samples from seven central Appalachian mines and two northern Appalachian mines were analyzed to assess the relative occurrence of surface-occluded silica. Results showed that the dust from central Appalachian mines actually had higher fractions of occluded silica, which may be due to extraction of large amounts of rock strata along with the coal. However, the central Appalachian mines also more silica particles overall (i.e., occluded + non-occluded) in terms of total number percentage of respirable particles.INTRODUCTIONResurgence of occupational lung disease among US coal miners, especially in the central Appalachian region, has been observed since the late 1990’s (Gibson, 2016; Zosky et al., 2016; Suarthana et al., 2011; Gamble et al., 2011; Antao et al., 2005; Attfield & Sexias, 1995). In addition to increased prevalence of simple Coal Workers’ Pneumoconiosis (CWP, or “black lung”), the prevalence of severe and rapidly progressive disease has risen dramatically (Almberg et al., 2018; Blackley et al., 2018a, 2018b, 2016, 2014; Graber et al., 2017; Cohen et al., 2016). While exposures to respirable silica have long been known to cause or play a role in diseases such as silicosis or progressive massive fibrosis (PMF), which is conventionally considered as the most advanced form of CWP, it is unclear whether silica is the only culprit in the recent outbreak of severe disease. Indeed, as disease rates have risen, both total respirable dust and silica concentrations generally appear to have declined since the late 1980s, based on regulatory monitoring data in the most affected mining districts (i.e., MSHA coal Districts 4, 5 and 12, which cover central WV, eastern KY and southwestern VA, and southern WV, respectively) (Figure 1). Of course, the latency of disease can vary and may be or more 10 years, but many of the most recent cases are likely to have resulted from exposures that occurred since the late 1980s."

Jan 1, 2019

By A. J. Partos

Table 4, Page 311 Table 4 Experimental Parameters from Straight Line Interpretation of Mohr Failure Envelope [ ]

Jan 1, 1991

[A Aall, Christian H., M49 D Mgr, American Metal Climax, Inc., 61 Broadway, New York 6, N.Y. Aaroe, S. L., A54 B Sales Mgr, The W. S. Tyler Co. of Can. Ltd., St. Catharines, Ont., Canada Abalos, Teodulo Q., J57 A Foreman, Lepanto Cons. Ming. Co., Mt. Province, Philippines Abbass, G., M55 P. O. Box 680, Hong Kong, China . Abbitt, James M., A54 770 Sole Blvd., Bartow, Fla. Abdullah, M. Y., J53 Dept. of Mines Res. Div., P. O. Box 1016, Tiger Lane, Ipoh Perak, Malaya Able, John F., Jr., J53 A Ming Engr, USA SIPRE 1215 Washington Ave., Wilmette, Ill. Abell, Leo M., M31 B Conct Supt, Phelps Dodge Corp., Morenci, Ariz. Abenius, Hakan Wilhelm, M52 A Mng Dir, Stora Kopparbergs Bergslags AB, Falun, Sweden Abenoroth, Harry F., A57 Natl. Carbon India Ltd., 18A Brabourne Rd., Box 217, Calcutta, India Abercrombie, Harry W., J56 1645 Camphor Dr., Lakeland, Fla.]

Jan 1, 1961

By Robert L. Lagace

The objective of this task was to perform theoretical analyses related to identifying and increasing the understanding of wireless propagation mechanisms in mines, and for predicting the performance ranges and limitations of proposed systems. This was to be achieved by building on and extending previous ADL work* and utilizing experimental data as they became available in the radio frequency bands of interest. B. TASKS Theoretical radio wave propagation investigations undertaken on this task centered on three areas. The first area dealt with extending previous UHF wireless propagation results*: to estimate the losses caused by the presence of haulage vehicles such as trains in coal mine tunnels; to estimate the propagation losses and wireless communication ranges expected along a longwall coal face tunnel; and to assess the applicability of previous analytical approximations to tunnels having reduced crossectional dimensions, such as those found in low coal and in the presence of haulage vehicles. The second area dealt with the development of a suitable propagation model to adequately explain the unexpected, highly favorable LF to MF band wireless radio wave propagation behavior experimentally observed in Consolidation Coal Co.'s Ireland mine. The third area dealt with the formulation of a model for evaluating the overall system transfer function and transmitter requirements for a hoist shaft LF communications system, taking into account the hoist rope/shaft transmission line characteristics, the cage and sheave wheel line terminations, the signal inductive couplers, and hoist shaft signal and noise data.

Jan 1, 1975

By J. R. Thoenen

During the past 6 years the Mining Division of the U.S. Bureau of Mines has prepared many information circulars containing valuable technical data covering the operating details of mining and ore-dressing plants throughout the United States, Canada, Mexico, and other countries. These papers, written for the most part by operating officials in the field, have been designed to comprise a reference library for the operating engineer. In order to make the information contained in these publications more readily available to the busy engineer the enclosed series of reference tables has been compiled. The tabular arrangement is by subject rather than alphabetical order, thus avoiding the bulk of an alphabetical index.

Jan 1, 1935

By A. A. Holland

Introduction The world's largest known deposits of natural sodium sulphate (Glauber salt), generally termed 'alkali ' throughout western Canada, are located in the Province of Saskatchewan: reserves are estimated to exceed 200,000,000 tons. These are surface deposits resulting from the recent or present-day natural evaporation of brines, in which respect they are similar to those occurring in certain other parts of the world, as in semi-arid sections of the United States, Russia, Germany and Austria. In some areas, underground deposits formed hundreds of thousands of years ago have been _encountered in drilling, and indications are that they also were formed under arid or semi-arid conditions. The master key to the formation of deposits of natural sodium sulphate, wherever they occur, is a climate, either past or present, under which evaporation exceeds precipitation over a considerable period of time. Commercial development of the Saskatchewan deposits began about thirty years ago. Previously, the demand for sodium sulphate had largely been met by salt cake produced as a by-product in the manufacture of hydrochloric acid from common salt. The rapid increase in the production of Kraft paper and, more recently, the development of synthetic detergent materials, have caused a marked increase in the market for sodium sulphate. This chemical gives the extra toughness to Kraft paper and is used in detergent compositions in proportions as high as 75 per cent. Saskatchewan now has six commercial plants producing natural sodium sulphate. Production from each in the fiscal years 1947 and 1948 is shown in Table I. The newest and latest plant is that of Saskatchewan Minerals, at Chaplin, which 1s designed to produce up to 150,000 tons of salt cake, 98.5 to 99.5 per cent pure, yearly. This is equivalent to about 24 percent of the total United States production of crude commercial salt cake for 1947.

Jan 1, 1949

[†AARONSON, ALFRED E., Vice-Pres., Mid-Co. Petroleum Co., Mid-Co. Bldg., Tulsa Okla. '18 ABADIE, EMILE R., Min. Engr Box 927, Porterville, Cal. '76 ¦ABADILLA, QUIRICO A. Student, Colorado School Of Mines, Golden, Colo. '20 ABBOTT, CLARENCE E., Gen'l Supt. Iron Mines Div., Tenn. Coal, Iron & R. I. Co., 1405 Minnesota Ave., Bessemer, Ala. '04] [ ]

Jan 1, 1925

By Robert Mehl

THE purpose of this investigation was to prepare high-purity iron-carbon alloys, to determine as precisely as possible the A3(GOS), the Acm(SE), and the A1(PSK) transformation temperatures in the meta-stable iron-iron carbide system (up to 1.4 per cent C), and to study the influence of carefully controlled and constant rates of heating and cooling (1/8 to 2° C. per minute) upon the transformation temperature and upon the resulting microstructure. Apart from the general metallurgical importance attending the completion of such a task, it will be noted that highly precise transformation temperatures are of interest and importance in the thermodynamic study of this system1. Several determinations of the iron-iron carbide diagram have been made. These suffer generally from the low purity of the alloys used, and from the application of methods of investigation of low sensitivity. Attempts to compare and weight the many data available in an effort to construct as accurate a diagram as possible have, in the main, been unsuccessful. In general, the wide differences in the results of different workers, the lack of complete analytical data, the omission of important details relating to the heat-treatment of the alloys, and the meager description of the methods of investigation applied, render such a process of averaging nearly meaningless. It may be seen from the summaries by Epstein2 and Körber and Oelsen1 that variations as great as 30° C. exist in the reported data on the A3 temperatures in iron-carbon alloys. For-tunately, the A3 temperature in pure iron is now known to be 910° C. ± 1° C.3 The best recent work on iron-carbon alloys is that of Esser4 on hypoeutectoid steels and that of Sato' on both hypoeutectoid and hyper-eutectoid steels.

Jan 1, 1937

Jan 1, 1970

By Lyman C. Hitchcock

The objective of this program was to determine the minimum luminance requirements for underground coal mining work from the working face to the first transfer point. The resulting data encompasses 114 visual tasks from conventional continuous and longwall mining methods representing the salient visual tasks found in the jobs listed. Cutter Operator Roof Bolter Face Drill Operator Airdox Operator Longwall Jackman Shuttle Car Operator Loader Operator Shot Fireman Continuous Miner Operator Longwall Head Conveyor Operator Longwall Tail Conveyor Operator

Jan 1, 1973

By J. B. Zadra, S. M. Shelton, R. B. Fisher, M. M. Fine

"INTRODUCTION An extensive test program is in progress by the Bureau of Mines to determine ways and means of recovering ferromanganese ore 5/ from the widespread domestic manganese and manganiferous iron deposits.Samples were received from the Stance property in southwestern Virginia, 12 miles northwest of Stoney Gap, in Bland County.The Stange mine is situated on the crest of Flat Top Mountain and is developed by open-cuts extending over several acres. The manganese deposit occurs in the Oriskany sandstone largely as a replacement of the sandstone, to some extent as breccia filling in the crusted parts of the sandstone, and as veins along joints, and bedding planes.The mine was first worked in 1917 and was operated during the war years. A long period of idleness was followed by intermittent operations in recent years. A small log-washing plant, consisting of a 20-foot log washer, was operated 1-1/4 miles northwest of the mine. The log-washer concentrates were crushed to minus- 1/2 inch and then washed in a second log washer to remove as much of the siliceous sandstone as possible. According to a communication from the operator, the double-washed concentrates were jigged and the jig concentrates marketed without further beneficiation."

Apr 1, 1942

By E. P. Youngman

By a decree of March 14, 1929,5 the President of the Faitian Repub- lic, considering it to be necessary, until the mining legislation of the Republic shall have been revised, to put into effect the mining law of Decem- Der 4, 1860 (relative to mines, diggings, and quarries), by the authority given in article 55 of the Constitution, declared the law of February 14, 1919, to be abrogated and the provisions of the earlier mining law (December 4, 1050) again to be valid. No concessions were granted under the law of 1919. All citations in this paper, unless otherwise designated, refer to the law of 1930.

Jun 1, 1932

By Coulter L. J

THE method of stope surveying as practised at the Mount Lyell Company's mines has been evolved out of the exigencies created by special conditions. It presents some novel features, and has proved effective for all requirements. All stope measurement work is brought under one complete system, to which office methods are standardized. Before proceeding to deal with the subject a brief description of the physical characteristics of the ore-bodies of each mine and the method of stoping will serve to show, cause ,for departure from ordinary survey practice.NORTH LYELL MINEThe ore-bodies of this mine occur on or near the conglomerate schist contact, and, being probably the result of replacements of both rocks, they rarely present any definite walls. It is usual for the payable material to merge into the respective countryrocks, and the limit of the occurrence is defined rather by assay value than by any distinct natural boundaries. The general configuration of these ore-bodies, therefore, is highly erratic both in horizontal and vertical section, so that, in order to obtain an accurate record of any occurrence, the measurement of the actual contour at short vertical intervals is essential.Stoping is carried out on a modification of the "rill." system, perhaps more properly described as "arched back" or "dome" stoping. Mullock rises are placed in as convenient positions as the erratic configuration of each ore-body will allow, and aroundthese rises the back is kept well arched, both longitudinally and transversely. The larger stopes are divided into arbitrary sections in which ore-breaking and mullocking are carried out in rotation, so that the whole of the excavation is seldom open for measuring at anyone particular time. Stacking or square-setting on the...

Jan 1, 1915

By D Will

RedrossThe Redross orebody averages 1 m wide, has a strike of 50 - 350 m, dips at 55° and has a basalt footwall and an ultramafic hanging wall. The most successful and innovative aspects of mining Redross were:•ore development innovations, 90 per cent of development was split fired with a shanty back profile to enable larger and more productive equipment to be used and resulted in higher development grades, improved project payback time and improved ore recovery;•hand held stoping using a multiple level, bottom up ‘V’ shaped hand held stoping method that allowed mining on multiple levels with hand held productivities between 50 and 90 tonnes per shift;•the use of 1 m cement pillars and 7 m high crown pillars were used to create multiple mining areas that enabled high overall production rates from hand held mining this orebody; and•the use of vertical cement pillars to enable hand held mining of adjacent stopes without leaving ore pillars.MarinersThe Mariners orebody averages 3 m wide, has a strike length of 50 - 250 m and dips at 50° with a basalt footwall and poor ultramafic hanging wall. The most successful innovative ideas of re-opening Mariners were:•Dewatering the existing mine workings utilising ‘oilfield’ technology by installing a long submersible pump in on existing pump rising main. This enabled the mine to be dewatered at rates up to 100l/ sec and helped overcome the 45 to 55 L/s inflows.•Overcoming the technical problems associated with Mining N07 ore blocks which had severely deteriorated from being underwater for five years by using reverse firing techniques to improve extraction rates and reduce dilution.•Mass firing a large mining block in the N08 with minimal void space because of deteriorating ground conditions.•Use of a longhole version of the Redross hand held mining method to achieve 100 per cent extraction of the N09 higher grade lenses.

Mar 21, 2011

By B. J. Arnold

During the past three years, coal samples covering a range of coal rank, ash content, size consist, grindability, and moisture content have been tested for their flow properties using a triaxial shear tester that measures the unconfined yield strength in a compressed sample of coal. The ratio of this unconfined yield strength to the sample bulk density is part of the equation used by handling system manufacturers to calculate the critical arching or critical ratholing diameter needed to ensure that coal will flow from bunkers or bins. This ratio also serves as an index to compare the flow tested. To test the applicability of the index to predicting problems with coal flow, a series of tests were conducted at CO Inc.'s Coal Quality Development Center (CQDC) in Homer City, Pennsylvania. Tests covering ranges in size consist, moisture content, and ash content were conducted by first filling a small two-ton bin with coal and then emptying the bin at a pre-set discharge rate. The actual discharge rate from the bin under the various conditions tested was measured. Samples of the coal discharging from the bin were collected. One sample was analyzed for ash, moisture, and size consist; another sample was sent to the Iowa state University for trivial shear tests (supplying an index measurement). Actual flowability results from the bin were then compared to the measured index to determine the applicability of the handleability index in actually predicting coal flow problems. This paper describes the correlation between handleability index and bin flow and explains the next stages of the project.

Jan 1, 1992

By Philip Arthur

The ISASMELT process is making a significant contribution to the global metals industry. ISASMELT furnaces are now operating successfully in eight different countries and treating approximately 3 million tonnes of concentrates and secondary materials per year. The process is currently used in both lead and copper smelting. The most recently commissioned plants were in Germany and China, one for treating scrap copper and the other treating low-grade copper concentrates. The Copper ISASMEL T furnace ("CIF") at Mount Isa Mines Limited ("MIM") has continued to set new operational records, with throughput of more than I million tonnes of concentrate per year and very low operating costs. This paper summarises the latest operational data from the Mount Isa Copper ISASMELT plant and outlines the successful approach to industrial R&D taken by MIM in the development of the ISASMEL T process.

Jan 1, 2003

By W. J. Cherones

This paper describes the history of the development and application of the electric mining shovel in open-pit mining, dea1ing particularly with far-reaching advancements in three primary areas: metallurgy, mechanical design and electrical systems. Hoist drives and crowd drives, including the Magnetorque and Electrotorque systems, and the integral propel drive are given close attention.

Jan 1, 1972

By Walter Pajalich

This Bureau of Mines report is a study of the organizational framework of the ferrous scrap industry, of the products produced, and of the factors affecting the consumption of ferrous scrap by the steel industry. Consumption data from 27 major iron and steel firms in the States of Illinois, Indiana, Iowa, Michigan, Minnesota, and Wisconsin during the period between 1957 to 1962 were grouped by type of iron and steel furnace production facilities to determine consumption pattern for various grades of scrap in comparison to ingot production, hot metal consumption, and home scrap generation. Grades of scrap affected by changes in scrap consumption were determined, and the pattern that emerged was analyzed. Correlation of scrap demand and its effects on scrap prices based on price of scrap receipts of No. 1 heavy melting scrap and No. 2 bundles in the Chicago area for the years 1957 through 1962 indicated that demand trends do not always affect the price of scrap, Past and present technological advancements in steelmaking processes are discussed, and their effects on the scrap industry are analyzed.

Jan 1, 1967

There are bound to be changes with age, so I should not have been surprised or disappointed when what I had considered as high ad- ventures were much fewer and more widely scattered in the last 20 years of my long and active business life. But such adventures came until I was past 80 years of age and no one could expect more than this. Frequent visits to mines in this country and Canada and directorships in Bralorne and its subsidiaries, Homestake Mining Co., Bradley Mining Co., and the Bunker Hill Co.; and Copper Range Co. and its great new White Pine mine in Michigan, lasted far beyond the usual retirement age. The least happy part of my last two decades of active life was the death or sickness of many of my old friends. Hubert d'Autremont, whose friendship no one could replace, died suddenly in 1946. Henry Carlisle and Temple Bridgeman, for many years office associates, had heart attacks that cut down their activities far too soon. Many other less intimate friends died or became ill, but I knew that with advancing years such losses were inevitable. These memoirs would be endless if they covered all of the unusual work and associations I found in the last 20 years. So I must confine the rest of my recollections to expeditions that would have thrilled any engineer at any time. Masaro Mine, Mindanao, Philippines The first of the four "high adventures" came late in 1949, when I was 65 years old. For over a month I had been discussing reported rich lead-silver-copper properties in the Philippines with Thayer Lindsley and other officers of Panaminas. A competent and agreeable "Elderly" (not as old as I was) engineer named Ward Williams had talked with Thayer about high grade mines in a remote part of the

Jan 1, 1976