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By E. R. Bauer

This report presents the results of a cooperative study between BethEnergy Mines Inc., Ebensburg, PA, a central Pennsylvania coal mining company, and the U.S. Bureau of Mines to investigate longwall development entry roof instability. In-mine mapping of geologic and deformational features was conducted to reveal the major ground control problems encountered during gate road development. In addition, mining-induced pillar load monitoring was used to indicate development loading on variously dimensioned gate road pillars and to determine if pillar yielding occurred. Finally, visual observations of a variety of roof control methods were used to determine the most effective support elements for controlling cutter roof failure.

Jan 1, 1992

By Arel B. McMahan

The U.S. Bureau of Mines investigated mines, prospects, and mineralized areas in the Owlshead Mountains Wilderness Study Area (WSA) in 1982. Within the WSA, subeconomic manganese, iron, zinc, and lead resources were identified at two mines; sample analyses indicate five other mines and prospects may have gold, silver, iron, manganese, and copper resources. Three mines examined adjacent to the WSA have identified manganese and iron resources; and sample analyses indicate manganese, iron, and gypsum resources may exist at two prospects. Greatest likelihood for future identification of mineral reserves is for manganese at the Black Magic Mine in the southeast part of the WSA. The southern half of the WSA contains nearly all identified mineral resources, and properties at which sample analyses indicate additional resources. The most significant are manganese and iron resources at the Black Magic Mine in the southeastern part of the WSA; and the Ellie, New Deal, and Owl Hole Mines adjacent to that part of the area. Manganese and iron minerals filled fractures and replaced limestone in brecciated and faulted contacts with intrusive granitic rocks. In the southwest corner of the WSA, sample analyses indicate four prospects may have gold and silver resources. These precious metals are in gouge zones along contacts where diorite has intruded volcanic rocks. A small identified resource at the Kennedy Boys Lead Mine in the western part of the WSA consists of quartz veins with zinc and lead minerals along a brecciated contact between granite and limestone roof pendants.

Jan 1, 1985

By E. P. Buxton, W. P. Yant, G. W. Jones

"Introduction. The data obtained in recent research work by the Bureau of Mines show that the analysis of the gases dissolved in underground waters may be used by the prospector or geologist as an additional aid in discovering new oil or gas fields. The hydrocarbons present in the water serve to indicate whether oil or gas sands exist in the region through which the waters have passed. A portable field apparatus has been developed by the bureau which can be used for removing and analyzing the gases dissolved in the waters. This apparatus and the method of u are described in this paper. Results are given of analyses made on waters from various localities, and the significance of these waters with reference to the detection of oil and gas.Any liquid, with the exception of mercury, if permitted to come in contact with eases or vapors will absorb a definite amount thereof. This action depends on the following factors: (1) The kind of gas; (2) the percentage composition of the eases in contact with the liquid; (3) the pressure of the gas; and (4) the composition and temperature of the liquid. For our present purpose it is only necessary is consider two of these factors - namely, the gas or vapor (natural gas and light petroleum vapor), and the liquid (water).If water of underground origin traverses a gas or oil sand it will absorb a definite quantity of hydrocarbon vapors, and will carry these vapors to the surface when tapped by a well. When the water is exposed to the air at the sur¬face, the eases and vapors will be given off and their place taken by oxygen and nitrogen from the air. Therefore, an analysis of the gases in waters reaching the surface from an underground source should be of value in determining whether these waters have traversed or came in contact with hydrocarbon-bearing strata. With the apparatus herein described it is possible to determine whether the vapors are mainly of natural gas on sition (methane CH1) and ethane (C2H6 ), or are come posed mostly of heavier petroleum vapors (ethane, propane (C3E8) and buttane (C4H10)."

Nov 1, 1923

By B. W. Gandrud

This is the third report published by the Bureau of Mines concerning the washability of Black Creek coal. Both of the former reports5/6/ dealt with the Black Creek coal at the Bradford mine, Dixiana, Ala., near the northeastern extremity of the Warrior field, whereas the present report is based on float-and-sink tests of coal from what is presumably the Black Creek bed near the southern extremity of the field. Although the Yolande Coal & Coke Co., owners of the property at Yolanda No. 6 slope, consider this opening to be on the Black Creek bed, the authors do not feel that there is as yet positive proof that this correlation is correct. There has been little or no development of the Black Creek bed in the Yolande Basin in the past, and a posy-tine identification of the bed at Yolande No. o will have to await further exploration and development. The Yolande No. 6 is an exploration slope 3/4 mile north of Rockcastle, Ala. The slope is approximately 400 feet from top to bottom on a dip of 18° As fax as the authors can ascertain, coal has never been produced commercially from the Black Creek bed in the southwestern part of the Warrior field. Exploration work in the past has indicated that the Black Creek coal in. this area is extremely friable and high in sulfur. Extreme friability would naturally discourage its' use as a domestic and railroad fuel, and high sulfur content would be a disasvantage in its use for coking coal. The present study of this coal has been made with particular reference to sulfur elimination on the assumption that it would make a good coking coal provided enough of the sulfur could be eliminated by washing.

Jan 1, 1939

By R. F. Selden

The material in this paper is intended simply, to be an inquiry into some of the theoretical aspects of the occurrence of methane and carbon dioxide in coal, with a brief resume of the more recent literature. Several discussions on various phases of the subject have been published, a few of which (4, 20, 25, 88, 90)4/ have more or less extensive bibliographies of tie earlier literature. In large measure the pertinent literature deals with the unusual aspects of the subject, and in consequence it might appear that the normal aspects have not been given due consideration here. The latter information is largely a matter of practical field experience, and since that which is normal to one locality is often abnormal to another no sharp differentiation appears to be necessary or, in fact, possible. No attempt will be made to present a critical discussion of the relations between the presence of gases in coal and pertinent geologic features or mining practice. Although the presence of foreign gases in the ventilating air of many mines is not particularly noticeable, in many others the evolution of methane and perhaps small amounts of carbon dioxide (or sometimes the reverse - large amounts of carbon. dioxide with perhaps sore methane) is quite apparent.

Jan 1, 1934

By R. F. Selder

The material in this paper is intended simply to be an inquiry into some of the theoretical aspects of the occurrence of methane and carbon dioxide in coal, with a brief resume of the more recent literature. Several discussions of various phases of the subject have been published a few of which (4, 20, 25, 88, 90) have more or less extensive bibliographies of the earlier literature. In large measure the pertinent literature deals with the unusual aspects of the subject, and in consequence it might appear that the normal aspects have not been given due consideration here. The latter information is largely a matter of practical field experience, and since that which is normal to one locality is often abnormal to another no sharp differentiation appears to be necessary or, in fact, possible. No attempt will be made to present a critical discussion of the relations between the presence of gases in coal and pertinent geologic features or mining practice. Although the presence of foreign gases in the ventilating air of many mines is not particularly noticeable, in many others the evolution of methane and perhaps small amounts of carbon dioxide (or sometimes the reverse - large amounts of carbon dioxide with perhaps sore methane) is quite apparent. The presence of small quantities of carbon dioxide can be attributed to oxidation of the carbonaceous matter exposed to the air. In the few cases in which this explanation is not sufficient, obviously the carbon dioxide must escape as such from the coal and neighboring strata.

Jan 1, 1934

By Henry C. Meeves

The Bureau of Mines, between 1956 and 1963, examined 18 major pegmatite districts in Arizona, Colorado, New Mexico, South Dakota, Utah, and Wyoming to evaluate their content of beryllium, a material in short domestic supply that has become increasingly important to modern industry. This examination report includes the salient statistics on the production of pegmatite minerals other than quartz and feldspar; and brief descriptions of 170 specific pegmatite deposits.

Jan 1, 1966

By V. F. Parry

[Subbituminous coal or lignite when stored in random piles or in ordinary bins in which the temperature fluctuates and air circulates quickly undergoes objectionable physical and chemical changes, which decrease the utilization value of the fuel and increase its tendency to ignite spontaneously. Slacking takes place, and the heating value decreases. These changes are accelerated by fluctuations of temperature and by circulation of air through the storage space. When such coals are exposed to the weather they lose moisture rapidly. If evaporation from the surface of a lump proceeds at a faster rate than that at which it is replaced by moisture from the interior, the rate of shrinkage at the surface is greater than that at the interior; consequently, stresses are generated at the surface which cause the coal to disintegrate. Likewise, when moisture is absorbed by the air-dried surface the outside layers expand at a faster rate than the interior, which results in further break-down. As these cycles are repeated the lump may disintegrate completely. Therefore, successful storage of low-rank coals depends on control of the factors that influence change of moisture.]

Jan 1, 1941

By Victor R. Spironello

The Bureau of Mines has conducted studies of the slags related to ferrous technology to evaluate experimentally acceptable substitutes for the auxiliary flux, mineral fluorspar, in steelmaking operations. Comparative heats were made in a 1/4-ton, pilot-scale, basic oxygen furnace (BOF) to evaluate a waste material known as "used potlining." Used pot lining is recovered from alumina reduction cells after its useful life and contains significant levels of fluorine and sodium in various compounds. This material in both lump and pelletized form provided adequately fluid slags, based on observations made during BOF operation. No adverse effects were found on furnace performance, metal and slag chemsitry, the strength of the steel produced, or the environment. Fluorine recovery in the slag was about the same as that obtained when using fluorspar, as were the losses to the scrubber water and solids. No difference was observed in furnace-refractory attack, as determined by the level of magnesia in the slag. The sodium recovered in the slag apparently also contributed to fluidity, since the fluorine input was at about two-thirds that of the fluorspar. Used potlining was determined experimentally to be a satisfactory substitute for fluorspar in basic oxygen steelmaking.

Jan 1, 1982

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

By Robert M. Baker

This document details the method whereby Allen Corporation of America gathered and analyzed data and developed an annotated bibliography of metal and nonmetal mine fire reports (1950-1979). The primary objective of this program was to develop the annotated bibliography which included MSHA accident reports and periodicals. Two additional objectives were to gather data on non-reportable fires and to conduct statistical analyses on the data to delineate trends. Data was acquired from three major areas: periodicals, MSHA fire reports, and mine safety directors. Data was separated into reportable fires (at least ½ - hour duration or injury), non-reportable fires, and opinion data. The data was then analyzed by time trends, state, ore, ignition source, burning substance, location, equipment, detection, duration, injuries, fatalities, and successful extinguishing agent. The authors make a number of recommendations: (1) improved stationary electrical equipment design and fire protection, (2) improved design of mobile equipment to separate combustibles from ignition sources, (3) improved maintenance, (4) improved housekeeping, and (5) improved training. The document is divided into two volumes and an appendix. Volume I contains data acquisition procedures, data analysis procedures, and conclusions and recommendations. Volume II contains a chronological list of mine fires and fifteen indexes to assist the reader in locating fire incident report of interest. The Appendix contains the annotated bibliography of over 300 metal and nonmetal mine fire reports and journal articles and a list of non-reportable fires.

Jan 1, 1980

By Terry S. Cory

This report describes the results of a measurement program to determine the broad spectral characteristics of both differential and common mode noise on phone lines in three coal mines; and, signal attenuation spectral characteristics on the same broad basis over phone line strings with taps/branches. The frequency range used was baseband -1000 Hz for resolution bandwidth ranging from 100 Hz near baseband to 30 KHz near I MHz. The signal attenuation measurements were performed on all three "legs" of taps where possible and applicable. Results were obtained comparing shielded and unshielded phone lines In one mine. The results include an improved electromagnetic noise chart for coal mines showing variations with types of mines, topology, and location of noise sources; also, fundamental high-frequency limit on untreated phone lines in coal mines is identified

Jan 1, 1981

By Richard L. Fowler

An automatic steering control system was designed, installed and tested on a coal mine shuttle car. The system utilizes sensors and associated signal processing electronics developed under a previous phase of this contract. The automatic steering system performs the routine guidance functions of turning corners and straight-through tramming. The shuttle car driver retains full authority of speed, braking, load and unload functions and at any time may exercise his option with manual override or steering. Steering information is generated from signals derived from the existing Lateral Guidance sensor subsystem, and all operational features of the previously developed open-loop system are retained. Above ground system tests were conducted in a simulated mine constructed of wood panel ribs. Results were in good agreement with prior hybrid computer simulations undertaken to validate the basic control system over a broad range of conditions and to select system parameter values. The automatic steering system was successfully demonstrated in the above ground simulated mine to USBM technical representatives. Designed to meet USBM permissibility requirements, the system is ready for a Phase II underground testing program. Testing in actual underground mine environment is expected to provide additional data regarding recommended performance improvements and implementation techniques.

Jan 1, 1975

The U.S. Bureau of Mines conducted a series of laboratory tests in a full-scale model to determine the respirable quartz dust capture efficiency of an irrigated-filter collection system while testing different filter densities, different filter materials, preconditioning water sprays, and wetting additives in the spray water. Impactor samplers were operated upstream and downstream of the filter unit to determine overall dust collection efficiency. The impactor filters containing the 0.7-to 4.7-J.l-m size fractions were analyzed for quartz content, and these data were used to calculate quartz dust collection efficiency. The results of this testing indicated that (1) increased ftIter density improved quartz dust collection, but also resulted in a significant increase in pressure drop across the filter, (2) an alternate synthetic filter material improved dust collection without increasing pressure drop, (3) preconditioning sprays mounted in the system ductwork can have a beneficial effect on dust collection, and (4) additives to the spray water did not significantly increase dust collection.

Jan 1, 1990

By T. C. Wesson

The need for elemental-analysis information on coal mine dust for use in health and safety research prompted this study by the Bureau of Mines. Neutron-activation and X-ray fluorescent techniques were used to obtain five-element analysis (silicon, aluminum, iron, calcium, and magnesium) on 444 samples from 68 coal mines in 10 States. From these analyses, the average composition of the dust in coal mines was determined. The contribution of the primary dusting material (limestone dust) to the makeup of coal mines was shown. Regional differences in mine-dust composition were indicated.

Jan 1, 1974

By W. W. Weller

Thermodynamic values for scandium and its compounds are very sparse. This is evident upon examination of any of the commonly used compilations of thermodynamic data. For example, National Bureau of Standards Circular 5004 lists only four heat of formation values, two free energy of formation values, and four heat-capacity values for scandium compounds. The entropy of crystalline scandium is one of the most fundamental values that has been lacking. This Bureau of Mines paper reports heat-capacity data for scandium metal in the temperature range from 50° to 298° K., together with the entropy value at 298.15° K. derived from these data through application of the third law of thermodynamics.

Jan 1, 1962

The above referenced contract between Badger Manufacturing Corporation and the U. S Bureau of Mines was executed June 30, 1975, as a result of the request for proposals for innovative machine concepts. We selected the cutting machine category because of the obvious lack of technical progress in this field for many years: Phase I of the contract required blasting fragmentation tests to determine proper blasting patterns for use with the auger-type kerf cutting machine. Phase II required design concept development for a machine capable of cutting a circular void as an aid to blasting.

Jan 1, 1975

By J. R. Thoenen

[For several years the Bureau of Mines conducted tests on ground vibration t emanating from quarry blasting in an effort to determine an index of destruction for different types of structures. Results of these studies have been published in four Bureau of Mines Reports of Invitations as well as in several articles in the trade and technical press.5/ The first paper (3)6/ discussed the subject in general and gave results s of a few blasting records. Some tentative theories also were advanced. The second paper (4) discussed results s of records made from blasting in a number of quarries.]

Jan 1, 1940

By V. F. Parry

Subbituminous coal or lignite when stored in random riles or in ordinary bins in which the temperature fluctuates and air circulates quickly undergoes objectionable physical and chemical changes, which decrease the utilization value of the fuel and increase its tendency to ignite spontaneously. Slacking takes place, and the heating value decreases. Those changes are accelerated by fluctuations of temperature and by circulation of air through the storage space. When such coals are exposed to the weather they lose moisture rapidly. If evaporation from the surface of a lump proceeds at a faster rate than that at which it is replaced by moisture from the interior, the rate of shrinkage at the surface is greater than that at the interior; consequently stresses are generated at the surface which cause the coal to disintegrate. Likewise, when moisture is absorbed by the air-dried surface the outside layers expand at a faster rate than the interior, which results in further break-down. As these cycles are repeated the lump may disintegrate completely. Therefore, successful storage of low-rank coals depends on control of the factors that influence change of moisture.

Jan 1, 1941

By J. R. Thoenen

[For several years the Bureau of Mines has conducted tests on ground vibration emanating from quarry blasting in an effort to determine Fin index of destruction for different types of structures. Results of these studies have been published in four Bureau of Mines Reports of Investigations as well as in several articles in the trade and technical press.5/ The first paper (3)6/ discussed the subject in general and gave results s of a few blasting records. Some tentative theories also were advanced. The second paper (4) discussed results s of records made from blasting in a number of quarries.]

Jan 1, 1940