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By Mary S. Esfandiary

U.S. scientists attempting to maintain continuous surveillance of scientific information are confronted with two acute problems: The steady, even spectacular; increase in the volume of such information and the fact that much of it is published in unfamiliar foreign languages, According to the National Science Foundation, almost one-third of the world's scientific literature is published in languages that are read by less than 5 percent of U.S. scientists. Most scientists in the United States must rely on abstract journals and translations to obtain information on developments in research and investigations conducted in the non-English-speaking countries. However, there are problems involved in procuring suitable abstracts and translations and in obtaining such information as cheaply and rapidly as possible.

Jan 1, 1961

By A. T. Coumbe

This compilation of statistics covering competitive fuels consumed for heating of residential and commercial buildings is in response to numerous requests for data of this nature to show the relative changes in the demands for the different fuels in recent years. The figures presented cover the amounts of various fuels ant electric energy reported as used for heating dwellings and commercial buildings. However, the totals for gaseous fuels and electricity necessarily include amounts consumed for both cooking and lighting purposes, as these associated household uses could not be readily broken out. [ ] SOURCES OF FUEL AND POWER STATISTICS Liquid fuel: Mineral Market Reports of the Bureau of Mines covering annual Pales of fuel oil and kerosine. The fuel oil figures include grades 1 to h, reported as sold for space heating. Kerosine and grade 1 fuel oil delivered as range oil ore also included. Gaseous fuel: "Gas Facts" published by the Bureau of statistics of the American Gas Association. Thin source was used as It is believed that the data shown are representative of the actual market

Jan 1, 1953

By S. L. Windes

This report presents physical and petrographic properties of approximately 60 types of rock from operating mines or mineral-investigation projects and supplements Repot of Investigations 4459, Physical Properties of Mine Rock (hereinafter referred to as Part I). The physical properties evaluated include the following: Apparent specific gravity Apparent porosity Compressive strength Flexural strength (modulus of rupture) Impact touchiness Abrasion hardness Scleroscope hardness Modulus of elasticity (Yourg?s modulus) Modulus of rigidity Specific damping capacity Longitudinal bar velocity

Jan 1, 1950

By Raymond M. Stateham

Calculations based on data obtained from measurements of smoke from coal-fired powerplants predict that infrared imagers will be useful tools for smoke vision. Infrared imagers operating in the 3-to 5-um spectral region have been evaluated for this purpose. A mine opening 110 meters long was filled with smoke from burning coal, and two men, wearing breathing apparatuses, moved through the smoke to serve as targets. The men were detected and identified at 80 meters.

Jan 1, 1976

By J. W. Miller

This report deals with upgrading of the coal reserves of Raleigh County, VI. Va., to metallurgical standards. The data on samples herein correctly show the characteristics of the bed at the point where sampled and are used to indicate the general quality of the bed in the county. The principal results and conclusions are: 1. Raleigh County contains large reserves of high-quality, high-, medium-, and low-volatile coals. 2. The principal beds from which an increased amount of coal is expected to be mined in the future are: The Eagle, Powellton, No. 5 Block, Hernshaw, Fire Creek, and Pocahontas No.6.

Jan 1, 1954

By Donald P. Schlick

This report presents a representative cross section of methods success- fully used to ventilate continuous-miner places as well as various factors that should be considered when selecting auxiliary ventilating equipment. Line brattice can direct fresh air to the active face reasonably well, provided that adequate area for installation is available. Continuous mining equipment, however, often restricts clearances to such an extent that proper installation of line brattice is impossible. Consequently, in many instances face ventilation is inadequate; therefore, many methods of auxiliary ventilation for continuous-mining equipment have been developed and have been discussed in this study.

Jan 1, 1963

By Bruce Cantrell, K. L. Rubow

"INTRODOCTIONMeasurement of the contribution of diesel exhaust to respirable aerosol in mine environments has become increasingly important because of current concerns over the occupational health effects resulting from exposure to diesel emissions. In response to this, the U.S. Bureau of Mines is developing and evaluating new sampling methods for measuring diesel aerosol in underground mines. Two such techniques are being studied by the Bureau, size selective sampling and Chemical Mass Balance (CMB) modeling. These techniques use measurable physical or chemical characteristics of a mine aerosol sample to infer the amount of diesel particulate material contained in the sample.Size selective sampling is being adapted for measurement of diesel aerosol by the Particle Technology Laboratory (PTL) of the University of Minnesota under sponsorship by the Bureau. 1 It is based on the premise that diesel and mineral dust aerosol can be physically separated by size and collected during sampling using inertial impaction. An independent effort by the National Institute for Occupational Safety and Health to develop a size selective sampling technique was also sponsored by the Bureau.The second technique, CMB modeling, is being developed by the Bureau as an alternative measurement technique to referee the results obtained using size selective sampling.3 It compares measured trace element ""finger prints"" of aerosol sources with similar profiles of mine aerosol samples. From these, the portions of the sample contributed by each source can be determined. Results of these investigations in underground coal mines have confirmed that diesel and coal dust aerosol are of different size and can be measured separately using size selective sampling techniques.A major difference in diesel usage among underground mines is the requirement for exhaust gas cooling systems in coal and gassy noncoal mines. Nongassy mines usually employ limited exhaust conditioning in the form of catalytic converters, which have limited effect on primary exhaust particulate. The cooling system in most general use in gassy mines is the water scrubber. This device has little effect on most of the gases but removes particulate material from the exhaust. 5 Because of this, exhaust aerosol characteristics in nongassy mines are expected to be different. To see if size selective sampling techniques can be used in such mines, the Bureau and the University of Minnesota conducted a second study in three metal and nonmetal mines, two nongassy and one rated as gassy."

Jan 1, 1990

By George T. Motock

In Germany the extraction of lithium and its salts has been handled mainly by units of the two major concerns - Metallgesellschaft A, G. and Deutsche Gold und Silber Scheide Anstalt, both with headquarters in Frankfurt. Zinnwaldite, which belongs to the mica group, is the major source of the lithium-containing raw material in Germany. Lepidolite and amblygonite also are used when available, but they are imported, as there are no major deposits of these two minerals in Germany.

Jan 1, 1946

By Joseph J. Wallace

1. The investigation shows that there are two coal beds of major importance in Perry County from the standpoint of present production -Flag and Fire Clay -and two beds of minor importance -Haddix and Hindman. The Flag and Fire Clay beds contain the largest remaining known reserves. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 tons per acre-foot of coal in place, are estimated at 840 million short tons as of January 1, 1954. Of this total, 720 million short tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager for making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, these should be added to the total estimated reserves.

Jan 1, 1954

By Ernest W. Johnson

Diamond, drilling of some blast holes in stoning operations is practised in at least two iron mines in the Lake Superior district - the Soudan mine of the Oliver Iron Mining Co., on the Vermilion range at Soudan, Minn., and the Anvil-Palms mine, operated by Pickands, Bather & Co., on the Gogebic range at Bessemer, Mich. Diamond drilling, at the Soudan nine has partly replaced percussion drilling because of the extreme hardness of the ore and of the lean formation. According to Wolff,4/ the jasper or lean formation in this mine is the hardest rock regularly drilled in any commercial operation.

Jan 1, 1945

By Harold L. Rhodes

The Bureau of Mines has developed a method for determining the H2S content in natural gas samples. A gas chromatograph with a flame photometric detector was used to analyze samples with H2S concentrations ranging from 5,000 ppm to a minimum detectable limit of 0.01 ppm. A mass spectrometer was used to analyze samples containing H2S in amounts greater than 5,000 ppm. Methods are presented for preparing containers for H2S samples and for preparing standards using partial pressure and weighed standard methods, Sample collection techniques are discussed, as are analytical results which illustrate the loss of H2S while in the sample container and provide a basis for evaluating containers used for sampling and standard preparation.

Jan 1, 1979

By David E. Nicholson

In a Bureau of Mines investigation of the dynamic compaction of mine hydraulic backfills, two basic forms of mechanical vibration inducers were used and compared for effectiveness of compaction. Internal compaction, using concrete probe vibrators of various sizes, and external compaction, using plate vibrators} were studied and evaluated for use in underground stopes. An aluminum plate, which was light and displaced sufficient volume to remain afloat in fluid fill, and a steel plate were both used in the external compaction tests. Efficiency of compaction was better in studies conducted with internal probe vibrators. Tests were conducted in an underground backfilled stope with three different-sized probe vibrators (2-, 4-, and 6-inch-diameter) to determine an approximate area of influence. Results showed the areas of influence to be approximately 3, 4, and 5 feet in diameter, respectively, for the three different probes. Physical properties of hydraulic slurries were determined; preferred grain-size distributions, water exudation properties, and water contents of hydraulic slurries are reported. The best compaction results were obtained with moderately well-graded, fully saturated backfills, with slow rates of water exudation, which were capable of remaining in a semifluid state during the compaction process.

Jan 1, 1967

"Initiated as a part of the Bureau of Mines program for development of strategic minerals for national defense, various mines in the Poughkeepsie Gulch and Mineral Point mining districts were examined by C. R. Wilfley, W. R. Hamilton, .and N. E. Wvvlwy, Jr., Bureau Of 'Mines engineers, in July and August 1943, July 1944, and September 1945. In a subsequent report a proposal was made to evaluate this isolated area 'of some 15 square miles located in Ouray and San Juan Counties, Colo.Reconnaissance work in the area was begun in June 1946. Mapping and sampling were begun in July and was completed in Pougkeepsie Gulch and extended westward to include the Hendrick Gulch area of the east side of Ironton Park. Project work was recessed for the winter on October 15, 1946 after approximately 6 square miles of the Poughkeepsie Gulch,district been mapped and 801 samples had been taken.In this report the physical features, climate, and ore deposits districts are described, and a brief history of mining and production lead, zinc; and silver is given.The individual mines and prospects in, the area are described in detail.A list of patented claims and ownerships is given in appendix I, and analyses of samples are tabulated in appendix II.The San Juan preliminary project was directed by Paul T. Allsman, chief, Salt Lake City Branch, Mining Division and was supervised by William M. Traver, Jr., supervising engineer, Colorado Field. Office.Chemical analyses were made by the Salt Lake City laboratory under the direction of H.E. Peterson, chemist, and S. R. Zimmerley, chief, Salt Lake City Branch, Metallurgical Division.Harold A. Waddington, president, Great Divide Mining & Milling Corp., and Ernest Miller, owner, Como Consolidated Mines, were particularly cooperative in making available maps and data concerning their properties."

Sep 1, 1949

By Robert Stefanko

The growing demand for energy during the post World War I and World War II periods has prompted underground coal production to increase rapidly. This has been met primarily by mine mechanization, resulting in the development and application of new mining machine types. Correspondingly, the total connected horsepower of each machine as well as the number employed has enlarged rapidly since 1950. (2,3,9,14,16,17) Electrical consumption for each mine has also grown. In the early years of mining electrical applications, only d-c power was utilized underground. Yet, d-c machine limitations were soon realized, and many a-c systems were substituted to permit economic and efficient utilization of a-c distribution and motors. Due to the attractive torque characteristics, ease of distribution and speed control, several traction applications have continued to be powered by d-c motors. The result has been the now prevalent use of mixed a-c/d-c mine power. However, augmented electrical power employment seems to have added to underground coal mining electrical accidents.

Jan 1, 1974

By Nadia C. Miller

In situ metals research to characterize the hydrology of a fractured crystalline rock mass in under-ground mine stopes is discussed. The objective of this study was to find the potential direction, velocity, and concentrations of a lixiviant plume, should leaching solvents (lixiviants) escape from a test stope. The study was conducted by the U.S. Bureau of Mines at the Colorado School of Mines Experimental Mine in Idaho Springs, CO. Since this was a method evaluation site, the lixiviant was simulated using water and acceptable tracers. The site is located in moderately fractured Precambrian migmatite-biotite gneisses of the Idaho Springs Formation. The data required for the characterization were obtained from geologic maps and reports, core logs, and air and water permeability tests. The acquired data were analyzed and applied to a computer model that calculated' the characteristics of a lixiviant plume originating at the stope. A sensitivity analysis showed that dispersivity, ground water velocity, fracture porosity, and fracture spacing had notable effects on the concentration of the plume. Assuming a saturated rock mass, the lixiviant plume would disperse to undetectable levels in a very short time because of a high fracture density at the mine site.

Jan 1, 2010

1.1 Bituminous-Coal and Lignite Dust. - Carboniferous material having a volatile ratio of 12 percent or more by weight and a fineness such that the material passes through a No. 20 sieve. 1.2 Active Underground Workings. - Underground places in which men are required to be or to pass through in the performance of normal mining operations for the production of coal. 1.3 Working Areas. - Underground areas where bituminous coal and lignite are mined, specifically: (a) Face. - The solid surface of the unbroken portion of the coalbed at the advancing end of the working place. (b) Face Area. - The working area inby the last open crosscut in an entry or a room, including the pillar being extracted or longwall being mined. (c) Room. - A place abutting an entry or airway where coal has been mined and extending from the entry or airway to a face. (d) Crosscut (Breakthrough). - Passageways or openings cut through a pillar to connect adjacent entries or rooms. 1.4 Entry. - Underground haulageways, travelways, and airways, except working areas as defined in section 1.3. (a) Active Entry. - An entry in which coal is being mined from a portion thereof or from connected sections. (b) Parallel Entry. - Usually an intake airway parallel to the haulageway. (c) Back Entry. - Usually a return airway parallel to the haulageway.

Jan 1, 1960

By C. B. Daellenbach

A prototype particulate size analyzer system was developed that would rapidly determine size distributions of homogeneous and two-mineral materials in the 74-micrometer (200-mesh) to 7-micrometer size range. The system sizes particles in a series of hydrocyclone elutriation steps and senses the weight of the five sized fractions by nuclear attenuation techniques. Size distribution of materials was determined from experimentally developed mathematical relationships that existed between particulate weight and the measured transmittance of gamma rays from an Americium-241 source. In the developmental phases, size distributions of three minerals (quartz, magnetite, and hematite) and a laboratory prepared two-mineral mixture of quartz and magnetite were accurately determined by the prototype system. In later stages of the investigation, semiconcentrates, an intermediate magnetic product from a taconite plant, were evaluated. Using 25-gram feed samples of this industrial material, the analyzer system was found to predict weight percentages for individual size fractions with an accuracy of ±0.85 percent or better at a 95-percent confidence level.

Jan 1, 1974

By R. J. Gunderman

Redesigns of the operator compartments on a continuous miner and on a face haulage vehicle are described. The objective was to optimize the compartments within limitations of existing equipment and functional configurations. Both safety and production should be improved through more comfort for the operator and more natural placement of controls. Design guidelines supplied by the Bureau from a previous contract were used along with human factors analyses to determine requirements. Mock-ups were fabricated from layouts and used to refine design details. The new compartments were implemented and the machines evaluated underground. Comments and reactions to both machines were favorable.

Jan 1, 1978

By J. Roger Loebenstein

This report presents a U.S. Bureau of Mines study of the flow of arsenic-containing materials in the United States, based on the best data available in 1991, includes a consideration of arsenic as a byproduct of the processing of nonferrous metals, the fate of arsenic in manufacturing wastes, the quantity of arsenic used in products, tile fate of arsenic in dissipative uses, and the useful life of discarded products. Where possible, estimates are given of the amounts of arsenic lost from the materials flow. Arsenic byproduct of mining nonferrous metals. Historically, most U.S. production has been from the states of Montana, Washington, and Utah. The smelters in these states are believed to be the areas of the country where arsenic is most concentrated in the soil, tailings ponds, and waste dumps. Since the closure of the last domestic producer of arsenic in 1985, all arsenic has been derived from imported sources. Historically, arsenic was important in agricultural applications as an insecticide, herbicide, and cotton desiccant. As the environmental movement gained momentum and the toxicity of arsenic became better understood, most of the agricultural uses for arsenic were banned. Beginning about 1975, the use of arsenic as a wood preservative began to grow. After 1980, wood preservative uses became more important than agricultural applications. By 1990, 70% of the arsenic consumed in the United States was used by the wood preservative industry and 20% by the agricultural industry. The major source of domestic arsenic emissions in 1989 was from the U.S. copper processing indus¬try. About 7,800 mt/yr of arsenic was discarded in leach dumps, tailings, and slag. Another 800 mt/yr was liberated to the atmosphere and 1/100 mt/yr was exported in copper concentrates. On the consumption side, 9,200 mt/yr was lost, mostly from dissipative agricultural uses and the disposal of obsolete arsenical products.

Jan 1, 1994

By E. J. Gleim

Contact with trolley wire in the mines of the United States has taken a considerable toll of life throughout the years that trolley locomotives have been employed as a means of' transportation. A study3/ of the records over a 15-year period for one State alone showed that, of 98 fatalities resulting from contacts with electrical circuits and equipment, 75 were caused by direct or indirect contact with unguarded trolley wire in coal mines. The law relating to guarding trolley wires in the mines of this particular State, as amended in 1935, reads in part as follows: "All trolley wires carrying 220 volts or more, and less than six feet six inches above top of rail, must be guarded at all points under which men and animals are required to pass***,'" The natural conclusion to be drawn from such records is that lack' of guards or shields must be held responsible for these fatalities. As a preventive measure, it has been advocated that every foot of trolley wire in mines should be guarded. Although some such drastic steps may appear to be amply justified, closer examination of the records nor this and other coal-mining States shows that absence of guards is not entirely responsible; but rather that other factors, such as carelessness and neglect it the observance of certain well-established simple rules concerning installation and location of trolley wires, also are responsible. In other words, if trolley wire is installed carelessly and its maintenance is neglected, it should not be expected that the mere installation of guards will overcome such carelessness and neglect. This publication discusses Various types of guards that have been used in Coal and metal mines of this country, together with related steps bearing upon the problem of 'preventing shock and fatalities from contacts with trolley wire. The material herein contained is taken largely from Information Circular 6577,4/ now out of print, and has been revised to include some types of guards that have been used in metal mines, together with a discussion of guard materials not covered in that publication.

Jan 1, 1945