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Two coal seams were selected and the conceptual designs were based on the geological and physical conditions typical of these seams. As a result of the screening process presented below, the two coal seams selected were the Lower Kittanning Seam in central Cambria County, Pennsylvania and the Pittsburgh Seam in northwestern West Virginia and southwestern Pennsylvania. SELECTION PROCESS FIRST SCREENING OF LONGWALL OPERATIONS The list of longwall operations prepared in Phase I and included in the Phase I report, was used as the basis for a first screening. From this list it was determined which longwall operations were not in the Appalachian coal fields and not in a coal seam of the thickness range of 42 to 72 inches. The first screening eliminated 30 of the listed operations, leaving 48.

Jan 1, 1976

The design, specification, and performance evaluation of the Communications and Location portions of a Coal Mine Rescue and Survival System are described. The work was performed as part of a nine month effort to develop a mine rescue and survival system using existing technology and state -of-the -art hardware as recommended by the National Academy of Engineering. Three basic subsystems were developed, one for survival, one for communications/location and one for rescue. This report and related equipment manuals describe only the Communications/ Location Subsystem which was designed, fabricated, and tested by the Westinghouse Georesearch Laboratory in Boulder, Colorado. Two basic technologies were used. Electromagnetic signals propagating through-the-earth provide voice downlink and coded beacon up-link communications. Seismic methods were developed to provide means for locating trapped miners. Seismic signalling also provides a backup means for communications. Parallel development programs for the electromagnetic and seismic portions of the system were conducted. The resulting hardware and software have been partially tested in coal mines and under simulated emergency conditions in order to evaluate system performance. The results of these tests are discussed. Further testing is recommended in order to establish quantitative performance limitations tinder a variety of environmental conditions and to develop methods for improving system performance.

Jan 1, 1971

By J. W. Adams

Two different techniques were wed to make measurements of the absolute value of electromagnetic noise in an operating hardrock mine, Grace Mine, located near Morgantown, Pennsylvania. Diesel-powered haulage equipment is used in this mine, and the electromagnetic noise environment it creates was measured to see how it differs from the environment created by electric-powered haulage equipment. One technique measures noise over the entire electromagnetic spectrum of interest for brief time periods. Data are recorded using broadband analog magnetic tape and are later transformed to give spectral plots. The other technique records noise amplitudes at several discrete frequencies for a sufficient amount of time to provide amplitude probability distributions. The specific measured results are given in a number of spectral plots and in amplitude probability distribution plots.

Jan 1, 1974

By Carl Belser

This report on tungsten in Ouray, San Juan, and San Miguel Counties, Colo., is one of a series describing results of studies on the tungsten potentialities in Region III, Bureau of Mines. The San Juan tungsten deposits occur in an area of 250 square miles, centering near the common corner of Ouray, San Juan, and San Miguel Counties (fig. 1). Field work supporting these studies was done in May 1954. Bureau of Mines reports prepared from investigations made during World War II and under the Defense Production Act of 1950 were reviewed.

Jan 1, 1956

By R. J. Matetic, J. S. Peterson, P. G. Kovalchik

The National Institute for Occupational Safety and Health (NIOSH) has initiated a study of a roof bolter to reduce noise exposure to mine roof-bolter operators. An important segment of this research entails determining the affect of various drilling configurations on the performance (penetration rate) and sound power emissions when drilling into granite. Test conditions included using various combinations of rotational speeds and thrusts, using 2.54- and 3.49-mm- (1- and 1 3/8-in.-) diameter hexagonal and round drill steels, using vacuum and wet conditions and using drill media of differing compressive strengths. This paper details the affects of each of these variables on the performance and sound power level emission. When drilling into granite, it was found that wet drilling generated lower sound power levels and performed better than vacuum drilling.

By R. A. Kearns

Biennially the Bureau of Mines issues a list of equipment that has been accepted as approved or permissible during the two calendar years immediately preceding the date of publication of the listing. By so doing the mining industry is kept informed of the availability of the latest equipment for safe use underground. This list supplements Bulletin 543, Permissible Mine Equipment Approved to January 1, 1953; Information Circular 7722, Permissible Mine Equipment Approved During the Calendar Years 1953-54; Information Circular 7840, Permissible Mine Equipment Approved During the Calendar Years 1955-56; and Information Circular 7957, Permissible Mine Equipment Approved During 1957-58. This list includes equipment meeting those standards that have been revised since Information Circular 7957 was .issued. Schedule 16E,4 a revision of Schedule 160, was approved May 19, 1960.

Jan 1, 1961

By D. Randolph Berry

Volume II contains appendices which explain and document the recommendations of Volume I. The following topics are covered: Appendix A Discussion of Recommended Guidelines Appendix B Worldwide Use of Oxygen Self-Rescuers Appendix C Hypothetical Use of Oxygen Self-Rescuers in Post-1972 Coal Mine Explosions and Fires Appendix D Vibration Testing of SCSRs Appendix E Testing of In-Service Chemical Oxygen SCSRs Appendix F Discussions with Representatives of Underground Coal Mining Appendix G Recommendations for SCSR Storage Containers Appendix H Example SCSR Storage Plans Appendix I Testing of In-Service Compressed Oxygen SCSRs Appendix J 30 CFR 75.1714, 30 Regulations Pertaining to Self-Rescuers

Jan 1, 1981

A knowledge of the mechanics of wave propagation through the earth is essential if reliable communication systems are to be designed for coal mine environments. To obtain a reliable basis from which accurate propagation predictions could be drawn, a series of theoretical Studies have been prepared for the Bureau of Mines by Mr. Ramsay Decker of Spectra Associates, Inc. through a subcontract with Collins Radio Group. These reports formulate the analytical techniques from which wee may derive frequencies and antenna configurations that yield the optimum signal-to-noise ratios over the greatest distances in mine environments. The reports of sections 2 and 4 deal with analytical techniques for determining the signal-to-noise ratio within a mine environment for loop-to-loop and line source-to-loop antenna configurations. The analytical results of these reports were then implemented into computer programs to obtain predictions concerning through-the-earth signal propagation. These preliminary predictions are based on noise data compiled by Bensema, Maxwell and Stone, and WVU prior to the extensive research conducted by the National bureau of Standards (NBS). These initial measurements indicated a 20- to 30-dB lower noise level than that measured recently by N BS. The recent NBS data is that used by Collins in the final predictions.

Jan 1, 1974

By Michel C. Frippel

This section of the Minerals Yearbook reviews the minerals industries of 27 countries: the 12 nations of the European Community (Belgium, Dermark/Greenland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Portugal, Spain, and the United Kingdom); 6 of the 7 nations of the European Free Trade Association (Austria, Finland, Iceland, Norway, Switzerland, and Sweden); Malta; the 8 Eastern European economies in transition (Albania, Bulgaria, Czechoslovakia, Hungary, Poland, Romania, and Yugoslavia); and the U.S.S.R. Western Europe Western Europe [loosely defined to include the 12 nations of the European Community (EC) and the 7 nations of the European Free Trade Association (EFTA)] is the single largest trading area and consumer of raw materials in the world. If Western Europe was at one time an important mining sector, it has now increasingly relegated the role of supplying minerals for its minerals processing industry to the more minerally endowed countries in North and South America, Africa, and Australia. In this regard, Western Europe is the most important determinant of raw materials consumption (and thus, indirectly, raw materials production). Western Europe has significant reserves of industrial minerals but has limited availability of metalliferous raw materials. It, therefore, imports significant quantities of the latter and ranks along with the United States and the U.S.S.R. in the production of refined metals. Nonetheless, there is an inherent tendency to underestimate the importance of Western Europe in the world of minerals, both as a minerals processor and raw materials buyer. The reason for this is that Western Europe is generally thought of on the basis of individual nations rather than as a whole. Viewed in this limited context, the United States, the U.S.S.R., and Japan appear to dominate the world economy. Viewed as one regional area, however, Western Europe includes the fourth (FRG), fifth (France), sixth (United Kingdom) and seventh (Italy) largest economies of the world, all bordering on one another. With the remaining 15 EC and EFTA countries, Western Europe has a land area approximately 40 % of that of the United States, exceeds the U.S. population by 50 % and has a gross domestic product about the same as that of the United States.

Jan 1, 1993

By W. A. Grosh

Records show that much of the lead produced in the Upper Mississippi Valley lead-zinc field was taken from natural openings along crevice systems at shallow horizons or at the surface. During the early history of the district, the shallow deposits were worked intensively; but in recent years the production of lead, except as a byproduct of deeper mining for zinc ores, has not been significant. Considering the methods of early mining, the character of mineralization, and the fact that galena can still be found on the surface of the old digging areas, it was reasoned that enough mineralization might remain on and above bedrock to permit, through the use of modern equipment and methods, economical re-treatment of surface material in the digging areas.

Jan 1, 1960

By F. N. Kissell

The machine-mounted continuous respirable dust monitor (MMCRDM) is a fixed-location area sampling device developed for possible use at the working face of an underground coal mine. This device, based on proprietary technology known as the tapered element oscillating microbalance, has evolved over the past eight years through a cooperative effort of the former Bureau of Mines, MSHA, and the Rupprecht & Patashnick Company in Albany, NY. The capability to measure respirable coal mine dust levels on a continuous basis, rather than depending solely on periodic samples obtained from the traditional coal mine dust samplers, has been a goal in the mining industry for nearly two decades. Recently, an extensive series of laboratory and underground tests was conducted by NIOSH with the cooperation of MSHA and coal operators to test the performance of the MMCRDM In preliminary laboratory testing, the MMCRDM seemed to work well. However, in every underground test, when compared to reference samplers placed close to the inlet, the MMCRDM failed to meet the 25% accuracy criterion specified in the contract under which it was developed. Two reasons explain this failure: First, in most tests the bias (the relative discrepancy between the average MMCRDM concentration and the average reference sampler concentration) was too great. Second, the variability of the samplers used for reference comparison was too large. Finally, the underground testing of the MMCRDMs showed that they are quite unreliable at this stage of development. In the majority of mine tests, no more than 10 shifts of data were taken before the MMCRDM failed to function properly. Major breakdowns, requiring the return of the MMCRDM to the factory for repairs, occurred on average every 28 days. To be considered mine-worthy, MMCRDM reliability must be substantially improved. KEYWORDS Dust, coal dust, dust instrumentation, dust sampling, dust monitoring, black lung, pneumoconiosis

By Anderson Dana

THIS PAPER describing methods and costs of mining and preparing gravel and sand for market at the Port Jefferson plant of the Seaboard Sand and Gravel Corporation, is one of a series of articles on gravel and sand mining, prepared for and published by the U. S. Bureau of Mines, which is designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total costs, It is recognized that publication of total costs might in many instances cause embarrassment to individual producers, as well as to the industry as a whole. On the other hand, operating costs are essential to the technical [ ]

Jan 1, 1932

By J. L. Holman

The Bureau of Mines, at its Rolla Metallurgy Research Center, has devised methods for separating and reusing the major portion of waste plastics discarded in urban and industrial refuse. Waste plastic concentrates from a local collection drive, recycling center collections, urban refuse pilot plants, and the secondary metals industry were separated into three major thermoplastic families--polyolefins, styrenes, and vinyls--based on differences in density using a Bureau-designed sink-float-elutriation hydraulic separator. Other separation methods and systems such as air classification, jigging, liquid media, screening, and electrostatics were studied. Vinyl plastics contain up to 50 percent HC1. It was found that over 90 percent of the HC1 in vinyls can be recovered as usable hydrochloric acid by pyrolysis at 350° C. The remaining pyrolysis products which had heats of combustion in excess of 12,000 Btu/lb, could become valuable as a future source of energy. A characterization study conducted on eight chopped wire insulation wastes from secondary copper and aluminum processors showed that most wastes contained 2 to 7 percent residual metal and large percentages of vinyl. The residual metal content of some of these wastes was lowered to 0.1 percent and the vinyl portion segregated using various separation techniques. The research also suggests ways in which reclaimed thermoplastics may be fabricated into useful products.

Jan 1, 1974

By J. A. Kosek

Work has been carried out under Bureau of Mines Contract No. HO395132 to develop and fabricate gas sensors for mining applications. Promising new instruments have been designed, developed, tested and supplied to meet BuMines requirements. These instruments include prototype 1) remote-sensing, diffusion-type CO monitors for mine operation which can be operated in conjunction with a surface computer, 2) control modules for alternate in-mine readout of the remote diffusion type CO monitors, 3) personal CO diffusion-type dosimeters and 4) personal NO diffusion-type dosimeters. In addition, retrofit modifications were made to update and optimize operation of CO and NO2 direct-reading type detectors provided under a previous contract. Studies were conducted to evaluate and demonstrate the availability of stable, portable N02 calibration sources for NO2 instrumentation. The use of selected, commercially available cylinder sources for NO2 instrument calibration were recommended. Additional studies were also conducted to investigate the feasibility of instrumentation for rapidly monitoring CO, NO and NO2 in diesel exhaust.

Jan 1, 1981

By Alvin Kaufman

Following the gold discoveries of the late 1800's much was written regarding the vast mineral resources of Alaska, and much interest was aroused, and yet over the years little has been done to exploit those resources. Between 1906 and 1935 the Kennecott copper mines of the Copper River region were the keystone of the mineral economy (fig, 1). After the depletion of the Kennecott ore reserves and aided by the statutory rise in the price of gold, the yellow metal became the major mineral commodity. In recent years it has shared the honors with coal and sand and gravel. Although this trend should indicate the development of a stable, diversified mineral industry, yet the trend of production is downward. This report results from a study by the Federal Bureau of Mines to delineate the problems and to forecast the growth of the mineral industries in Alaska. The need for such a blueprint for the future was enhanced by the population explosion in the United States and the consequent eventual need for additional living space, as well as the current interest in new areas, and the necessity to develop reserves of strategic minerals.

Jan 1, 1961

By William H. Hamilton

This report describes the results and conclusions of the development and evaluation of a unique concept for a lightweight air powered drill tool for probe drilling in anthracite mines. A concept model of the lightweight air powered tool was constructed and evaluation testing conducted at the Kocher Coal Company Porter Tunnel Mine. The unique anchoring method proved to be extremely satisfactory and the overall light-weight air powered drill tool concept proved feasible. Based on the results of the concept model testing, two prototype production units were designed and manufactured. These prototype units proved to meet all of their design requirements of lightweight, portability, drilling controllability, structural integrity and miner acceptance. The need for a better bit and drill steel system, however, became evident during the testing program and recommendations are made for further investigation and development of a bit and drill steel system suitable for this application.

Jan 1, 1979

By J. W. Jensen

This report was prepared as a background reference for future publica¬tions concerning the damping capacity of metals and alloys. It contains a broad description of the theory and methods of measuring damping capacity and correlates the developments of the past decade in terminology, units, and techniques. Damping-capacity instrumentation at the Mississippi Valley Experiment Station, Rolla, Mo., is described. The bibliography contains over 150 references to recent articles, each tabulated as to material investigated and test variables, such as frequency, stress, mode of vibration, and temperature. INTRODUCTION After it discovered high-damping manganese-copper alloys before World War II, the Bureau of Mines began research on the damping capacity of alloys and has continued to expand this activity to the present time. In physical metallurgy, damping capacity has become an important research tool in the Bureau. The physical measurement of the damping properties of alloys was begun at the College Park laboratories, and later conducted at Salt Lake City under the direction of Dr. E. V. Potter. Among the many articles resulting from this work, Damping Capacity of Metals (108)3/ has received frequent men¬tion in more recent literature and describes briefly the methods of measurement employed at that time.

Jan 1, 1959

By H. D. Kline

This paper is one of a series being prepared by the Bureau of Mines on methods, practices, and costs in various mining districts in the United States. The paper describes mining and ore recovery methods common to the Batesville manganese district, Independence County, Ark., and gives the costs of producing merchantable ore by three operators whose methods were more or less typical of those of many other local manganese producers. The operating costs reported were those of Leonard Baxter at mines on Brooks Hill for the calendar year 1958 and Arkansas Mining and Exploration Corp. at Section 16 mine and the Searcy group of mines and Miller-McGee Corp. at the Diener mine during the first 6 months of 1959. Manganese are was mined in the district as early as 1849 and almost continuously thereafter until August 1959, when termination of the Government's domestic manganese purchase program resulted in complete cessation of mining activity. During those years, production came from more than 189 mines and properties, of which only a few produced as much as 30,000 tons of merchantable ore.

Jan 1, 1962

By Virgil A. Marple

It was the purpose of this contract to conduct research in several different areas of instrumentation used to determine the quantity of respirable dust in the mining atmosphere. One area of research was in evaluation of instruments including several respirable dust monitors, several types of photometers, and a QCM cascade impactor. An instrument evaluation chamber was developed to aid in evaluating the instruments in a dust atmosphere. Another area of research was investigations into new instrumentation concepts, such as a virtual impactor/photometer instrument, a new optical device which can be used as either an optical particle counter or photometer, a new personal respirable sampler, which employs an impactor instead of a cyclone as a preclassifier, and the development of a new cascade impactor, which deposits the particles uniformly on the impaction plate. Another area of research included the use of many of these instruments in two field studies, including a silica sand plant and a tungsten mine.

Jan 1, 1981

The principle activities of the Explosives Research Laboratory from July 1, 1961 to June 30, 1962, are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1962; in general, the research reported in these publications antedates the report period. Part 3 gives the results of an investigation which, although too limited to warrant separate publication, merits presentation in some detail because of current interest in ammonium nitrate-fuel oil compositions.

Jan 1, 1964