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By Kathleen M. Kowalski

This research explores the emergence of leadership in a crisis situation. The study by the U.S. Bureau of Mines focuses on three underground mine fires and the resulting evacuations. The subjects for this study are 48 coal miners, who evacuated the mines as part of eight escape groups, The subjects described their escape during an open-ended interview. Data were coded according to: (a) evidence of leadership behavior, (b) evidence of lack of leadership behavior, and (c) characteristics of the individual in each group who led the subjects out of the mine. During analyses, attributes of the leaders, who facilitated the escapes, were noted and compared as were instances of lack of leadership. The structure of the group leadership before the crisis was compared with the reality of the leadership during the crisis. Some groups experienced an apparent breakdown of leadership during their escape, while others witnessed the emergence of leadership. Consensus characteristics of the leaders, who emerged during these crises, are discussed and generalizations drawn. Research into leadership during emergency escapes is needed to provide information for training in prevention, escape, and rescue. The authors suggest questions for further investigation and topics for further inquiry into the area of leadership evolvement during crisis.

Jan 1, 1994

By C. W. Owings

Recent recommendations of the Bureau of Mines regarding, rock dusting to prevent dust explosions in coal mines have been issued as Mine Safety Board Decision 32 and printed as Information Circular 7109.5/ The last paragraph on page 2 of I. C. 7109 states: After a mine or any part of a mine has been rock-dusted, samples of dust for analysis should be taken from the floor, ribs, roof, and timbers at such intervals of time as will give apple warning of need far redusting in order to maintain the required minimum percentage of incombustible in the mine dust. Details of the methods of sampling and analysis are given in Bureau of Mines Information Circular 7113.

Jan 1, 1940

By Lucien Eaton

This paper describing the mining practices at Mine No. 1, Menominee Range, Mich., is one of a. series being prepared by the Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. It is felt that the publication of this information will be of interest and value to the mining industry at large and especially to operators whose mining conditions are similar to those described. ACKNOWLEDGMENTS The author is indebted to the superintendent, engineer, and mining captain of Mine No. 1 for much of the information presented.

Jan 1, 1929

By W. T. Benson

The nickel-bearing laterite deposits in the Pine Flat and Diamond Flat areas, Del Norte County, Calif., were investigated by the Bureau of Mines to determine the extent and nickel content of the two deposits and the amenability of the ores to metallurgical treatment. The work was based on drill-hole sampling and metallurgical tests in which attrition scrubbing and sizing, reduction roasting, and magnetic separation were used. Results of the sampling indicated that the deposits are comparatively small and are marginal or submarginal in grade. Metallurgical tests showed that no separation of cobalt from nickel and iron was made by sizing; however, a large portion of the chromium was separated. Reduction roasting and magnetic separation did result in upgrading the iron, nickel, and cobalt, and the simultaneous rejection of chromium.

Jan 1, 1963

By R. A. Busch, R. R. Backer, R. W. McKibbin

The Bureau of Mines conducted laboratory tests to determine the slur- ry transport and deposition properties of coal waste. A 188.5-ft pipe test loop was constructed with instruments to measure density, flow, and power and discharge, suction, and differential pressures. A 20-ton sample of Western coal waste was crushed and screened to 100 pct minus 1/2 in. Eight loop tests using this graded waste were run at slurry densities ranging from 1.15 (25 wt-pct solids) to 1.46 (60 wt-pct sol- ids). The resultant friction-pressure gradients ranged from 0.06 to 0.24 ft of water per foot of 4-in standard steel pipe. Particle-size degradation was significant. In a typical loop test lasting 25 min, the minus 200-mesh fraction increased from 19 pct to 34 pct. Deposi- tion tests showed that without the use of a flocculant, the slurries would not dewater when left to stand for 1 week. With flocculant, ad- ditional water was released; however, the settled slurries remained thixotropic. Further testing is necessary to determine their suitabil- ity for use as backfill material in active mines.

Jan 1, 1965

By Jr. Watts, B. K. Cantrell, D. H. Carlson, K. L. Rubow

"The use of diesel equipment in underground coal mines is controversial because ""whole diesel exhaust"" is regarded as ""a potential occupational carcinogen"" by the National Institute for Occupational Safety and Health (NIOSH). Threshold limit values (TLVs) are recommended for the gaseous pollutants; CO, CO2, NO, NO2, SO2, and some hydrocarbons emitted in diesel exhaust. There is, however, no TLV recommended for diesel exhaust aerosols (DEA) nor is there a standard method for sampling these aerosols.The University of Minnesota and the Bureau of Mines have collaborated to develop a personal diesel exhaust aerosol sampler (PDEAS) which utilizes size selective, inertial impaction and gravimetric analysis. During the field tests of this sampler, numerous air quality measurements were conducted in underground coal mines using diesel equipment. The objective of this report is to present these data and to assess the impact of diesel face haulage equipment on mine air quality.Air quality data were collected in four underground coal mines using continuous mining methods with diesel haulage equipment. Daily samples were collected at the section intake, haulageway, and on haulage vehicles. Both full-and partial-shift samples were collected using a variety of aerosol instruments, including the PDEAS and the micro-orifice, uniform deposit impactor (MOUDI) which sample the mine aerosol diesel exhaust fraction. Two of the mines were also monitored for the major gaseous constituents found in diesel exhaust CO, CO2, NO, NO2, and SO2. These measurements were made by either collecting bag samples for subsequent gas analysis or by Palmes dosimeters.The concentrations of CO, CO2, NO, NO2, and SO2, were well below regulated levels. The mine average DEA concentration determined by the PDEAS in the haulageway for the three mines surveyed using this instrument was 0.79 mg/m3, with a standard deviation of 0.19 mg/m3. DEA contributed 65% of the respirable aerosol, at this location. These results were the same as the mean DEA concentrations calculated from size distribution measurements obtained using the MOUDI. This was 0.78 mg/m3, with a standard deviation of 0.22 mg/m3."

Mar 1, 1992

By F. X. McCawley

The Bureau of Mines, in pursuing its goal of extending the life span of strategic materials, conducted field corrosion studies at the East Mesa Known Geothermal Resources Area (KGRA) in the Imperial Valley, Calif., to determine the optimum materials of construction for use in geothermal mineral energy resource recovery plants. These studies included characterization of geothermal environments and in situ corrosion testing. The corrosion resistance of 10 alloys exposed to 5 brine and steam process environments was evaluated using the low-salinity, high-temperature brine from geothermal well Mesa 6-1. Of these alloys, Hastelloy C-276, Hastelloy S, Incone1 625, titanium-2nickel, and 316 L stainless steel had excellent resistance to corrosion in all of the process environments; E-Brite 26-1 and 430 stainless steel had fair resistance. Although general corrosion rates for 4130 steel and 1020 carbon steel were substantially higher than those of the other iron-base alloys, these two alloys could prove useful in low-salinity process environments because of their low cost. Aluminum alloy 5005 was the least corrosion resistant alloy and pitted severely. Scales formed on all of the alloys in every process environment. Calcite, aragonite, and an amorphous silicate were the major components of the scales.

Jan 1, 1980

By A. J. Kauffman Jr.

The Petrographic Section of the Bureau of Mines, Northwest Electrodevelopment Laboratory, Albany, Oreg., annually examines thousands of minerals and rocks. Samples are received from mining, engineers, prospectors, and government agencies, both State and Federal. During the past 2 years certain uncommon minerals have been identified in the samples submitted. Eleven occurrences have been selected for reporting in detail. These selections were made because in most cases a new locality is involved. The data reported are the result of application of the latest techniques, and widely disseminated references concerning each mineral have been added for completeness. Several occurrences have been described by other investigators; in those cases new data have been supplied to supplement the already published information on these occurrences. No uranium-bearing minerals have been included; they will be treated in another paper. The Bureau of Mines does not make chemical analyses or assays for individuals or firms In direct competition with private laboratories. Mineral¬ogical examinations, however, are made for prospectors and the general public. Such examinations a call surface to determine whether the sample in question has possible commercial value. If it has apparent value, the sender is so informed, and suggestions as to its .Arc, development and marketing are offered. The latest scientific apparatus is available to aid in identification. The apparatus includes microscopes, both wide-field and polarizing, a Bunsen-type spectroscope for visual observation of the Zinc and band spectra of many elements, differential thermal apparatus for the examination of hydrous material, apparatus for cutting and mounting either thin sections for study in transmitted or polished surfaces for reflected-light studies, and a high-intensity magnetic separator for concentrating minerals according to their magnetic susceptibility. Also, available, but not an integral part of the Section, are several laboratory-type Geiger counters, a grating spectrograph, and X-ray diffraction apparatus. If need be, all of these tools may be employed to identify a mineral or rock.

Jan 1, 1950

By E. T. Bowers

The Accident Analysis (ADA) computer program was developed at the Spokane Research Center (SRC) to provide a rapid broad-based analysis of mining accidents. Because the Bureau of Mines often needs this type of information for the development of viable research programs the ADA program was written to access and analyze accident data available frog the Labor Department's Mine Safety and Health Administration (MSHA). This report describes the ADA program, the data it uses, and the potential value it has for planning mining research.

Jan 1, 1987

By Madan M. Singh

Hydraulic mining has been practiced in the United States since 1852 and many mineral commodities, such as gilsonite, phosphates, lead-zinc, silver ores and St. Peter Sandstone can be mined in this manner. In 1958, the U. S. Bureau of Mines initiated research into the mining of coal using these techniques.1-4 These early investigations were conducted in the 5000 psi pressure range. The large nozzle diameters used in this pressure range produced extremely high flow rates which created visibility problems at the coal face, and required removal of large amounts of water from the mining area. Besides, the production rates were not much better than with mechanical methods. This indicated that with higher pressures the water quantities might be reduced using the same or higher horsepowers but enhanced breakage. For this reason intensive investigation in material removal using fine water jets at extremely high pressures (50,000 psi to 100,000 psi) has been undertaken. This was not the entire reason for this contract from the Bureau of Mines, however. The contract objective is outlined later. IIT Research Institute has done pioneering work in high pressure jet development in the United States.5-8 Similar schemes have been investigated abroad. 9-13 Hydraulic mining of coal at relatively low pressures is successfully being done in the Soviet Union, Japan, Canada, and most recently, in Germany.

Jan 1, 1973

By G. W. Jones

The Bureau of Mines has advocated the use of stenches as warning agents in metal mines and in gas-distribution systems since 1920 A considerable amount of research has been conducted on ethyl mercaptan and other compounds to determine their effectiveness when used for this purpose.4/5/6/7/8/9/10/11/12/13/ Miners are warned of danger by a stench injected, in measured quantity, into a compressed-air line through which it is rapidly carried to the working faces, where it escapes from the compressed-air equipment and imparts a characteristic odor to the air. This method is not applicable to mines where only a limited number of com-pressed-air lines are used, as for example, many coal mines; the ventilation currents available in these mines may be too slow for warning purposes.14/

Jan 1, 1954

By A. Wahab Khair

"This paper presents an analysis of fracture mechanisms in coal subjected to bi-axial state of stresses, indentation of laterally confined coal specimen. Coal specimens were loaded to failure by the straight wedge indenters at various lateral confinement pressures. Strain distribution and acoustic emission characteristics of coal specimens under stress were recorded. The influence lines of vertical forces acting on the horizontal straight boundary of the coal specimen for each type of wedge indenter have been established using holographic interferometry technique. The effects of wedge indenter angle, confinement pressure, and coal anisotropy on fracture types, failure modes, and post-failure conditions were studied. The results indicated that combined application of holographic interferometry and acoustic emission monitoring techniques is not only suitable ·for studying deformability of heterogeneous and microscopically discontinuous material under stress but it also enhances the mode of fracture during the post failure stage. INTRODUCTIONOne of the relevant processes in the coal cutting technology is the application of indentation theories. Since most cutting tools in the coal industry are wedge shaped most of the indentation research is found for a wedge shaped tool.A wide range of behavior is found in different rocks subjected to the wedge penetration. A rock which is elastic brittle at standard pressure might become elastic plastic at high confining pressure (Gnirk and Cheatham, 1963). It was also observed that some rocks will merely be crushed and indented by a wedge whereas others will crack and form chips, furthermore the existence or non-existence of chips depends mostly on the geometry of the indenter, type of rock and the depth of penetration (Evans and Murrel, 1958). However, coal cutting technology is mostly explained by models which use rigid wedge to penetrate into a brittle material in which both crushing and chipping will occur (Evans and Murrel, 1958, 1962)."

Jan 1, 1988

By H. Leitch

In laboratory experiments, the Bureau of Mines investigated melting, quenching, and sulfuric acid leaching of alumina from mixtures of albite and anorthite, and from anorthosites containing 26 to 32 percent alumina. Variations in pouring temperature, quenching and leaching conditions, were studied with respect to the extraction of alumina and impurities. Virtually all of the alumina was dissolved by leaching melted and quenched California anorthosite in boiling 16-percent sulfuric acid solutions for 15 to 30 minutes. The leach solutions were readily separable from the solid residue by conventional thickening and filtration techniques. Only 2 to 5 grams of SiO2, Fe2O3, or CaO dissolved per 100 grams of alumina. The quantity of SiOz in solution varied inversely with the duration of the leach and with the concentration of the H2SO4 solution used. Melted and quenched Wyoming and Minnesota anorthosites with SiO2:CaO weight ratios of 4.3 and 3.2, respectively, were less amenable to sulfuric acid leaching than California anorthosite with an SiO2:CaO weight ratio of 5.3. However, excellent results were obtained on the Wyoming and Minnesota anorthosites by the addition of SiO2 to these materials before melting, in quantities sufficient to adjust the SiO2:CaO weight ratios of the furnace charges to between 4 and 6.

Jan 1, 1966

By Alan J. Fejes

As part of its mine subsidence research program, the Bureau of Mines and the American Electric Power Co. cooperated on a study, conducted at the Price River Coal Co. No. 3 Mine, directed toward developing the capability to estimate the surface subsidence resulting from longwall mining in a geologic, topographic, and mining environment common to coalfields in the Western United States. Subsidence was monitored at the No. 3 Mine over two adjacent longwall panels. The subsidence study area was reduced when the two planned panels were reduced in length because of equipment failure and a mine fire. Subsidence was measured for 21 months. Subsidence continued for 6 months after mining had been completed. A maximum of 2.2 ft of subsidence occurred over the two longwall panels mined at an overburden depth ranging from 300 to 1,500 ft.

Jan 1, 1986

By S. H. Ash

[On December 2, 1932, the Governor of California called upon the representatives of the mining industry of the State to attend a meeting at Sacramento to discuss ways and means of assisting is relieving some of its perplexing and extremely distressing problems, particularly the mounting cost of accidents which faces the industry with an industrial insurance rate for classification of $11.85 per $100 of pay roll, effective January 1, 1033. The significance of this fact is at once apparent when it is realized that the classification rates per $100 of pay roll for mining have steadily increased for some time, as follows: $3.91 in 1924, $5.54 in 1925 and 1926, $8.04 in 1927, $8.53 in 1928, $9.05 in 1929, $9.42 in 1930, $10.54 in 1931, $10.99 in 1952, and $11.85 in 1133. In other words, the cost rates have acre than doubled, wile statistics indicate that the accident rates nave shown an entirely different trend. At the meeting mentioned, one of the management officials sounded an effective keynote when he declared that a spade should be called: a spade. The perplexing problems of any industry can be approached best and remedies applied if that policy is kept to the front. It is appropriate to mention that high accident rates and a decrease in wages in recent years have unquestionably accounted in part for a unit cost rate, on a pay-roll basis; it also is well to explain that the policy years3 1926 to 1930, inclusive, are the years on which the accident-cost experience for 193: is based. That accident rates :lave not undergone the expected beneficial chance in California's experience is apparent in the words of a Bureau of Mines report:4]

Jan 1, 1933

By T. E. Bernard

The CO2-absorbent canisters used in four approved rescue breathing apparatus were investigated. A breathing machine was used to simulate human expiration with gas flow rates of 26, 37, and 48 1/min of 3.5% CO2 in air. The exit gas CO2 concentration, the pressure drop across the canister, and the exit-gas temperature were monitored. The absorbent capacities of the packed-bed canister designs were found to be dependent on flow rate within the range studied, while the capacities of the other designs were less affected. The radial canister had the least resistance to breathing while the complex bed design proved to be the most effective in utilization of the chemical. The overall results indicated that LiOH (lithium hydroxide) has the highest capacity for CO2 absorption among the absorbents tested. It can be used in a simple packed-bed design while maintaining acceptable levels of resistance and exit-gas temperature. Examination of oxygen supply with respect to CO2-absorption capacity suggested that it is desirable to closely match CO2-absorption capacity with the avail-able O2 supply to minimize the size and weight of rescue breathing apparatus.

Jan 1, 1979

By John C. Machisak

The Nation's mining and quarrying industries have again met the annual challenge to their ingenuity--that of reducing disabling work injuries among their employees. The effectiveness of management in facing this problem and in meeting this responsibility is evident from the results of the 1961 National Safety Competition. Three hundred ninety-three or 45.3 percent of the mines and quarries participating in the competition established a new record number of participants operating throughout the competition year without a disabling work injury. Another record established in the 1961 contest was the number of participants (868) enrolled in the competition. This annual safety competition was begun in 1925 and is conducted by the Bureau of Mines, U.S. Department of the Interior. It provides for six bronze Sentinels of safety trophies which are awarded each year to the winning participant in each group. Since its inception, the competition has exerted a strong influence in the field of safety promotion. The statistical record of its accomplishments over the years gives strong support to the theory that well-organized and well- administered safety programs are effective tools to be used to reduce the number of disabling work injuries. It stimulates and holds the interest of employees and management in accident prevention. Because of this, mines and quarries participating in the contest have a more favorable safety record than those operations not enrolled.

Jan 1, 1963

By S. H. Lorain

This paper is one of a series on mining methods and costs being published by the U. S. Bureau of Mines. The operations of the Quartz Hill Mining Co., near Dewey, Mont., afford an interesting example of the cost of mining small bodies of direct shipping ore; they also illustrate the effect of the unavoidable periods of unusually high exploration and development costs in this type of mining upon the cost per ton of producing ore. The importance of skilled geological guidance and the necessity of avoiding unnecessary overhead and capital expense at small mines are shown. Operating conditions at Quartz Hill are typical of those in many other mining districts of southwestern Montana. It is believed that the costs presented here may be of value in the preliminary estimation of costs to be expected by conservative operators under similar conditions elsewhere. The information contained in this paper was obtained during a visit to the Quartz Hill mine in August 1936.

Jan 1, 1937

By T. E. Green, E. F. Spano, W. J. Campbell

A combined ion - exchange X- ray spectrographic method was developed and evaluated for determining trace amounts of cobalt and nickel in high - purity tungsten and tungsten trioxide . The sensitivity for both cobalt and nickel is in the range from 0.2 to 0.5 μg ( 0.04 to 0.1 ppm , based on 5 gram samples ) . Accuracy at the 5 to 20 μg level is ±10 percent of the amount present . Approximately 16 hours elapsed time is required for analysis

Jan 1, 1963

By M. C. Malamphy

A general description of the activities and results of bauxite investigation by the Bureau of Mines at its bauxite project in Saline and Pulaski Counties, Ark., has been given in Report of Investigations 4251. The factual data obtained during the project are reported in a series of Reports of Investigation beginning with No. 4251, of which this is the thirteenth. The data are accompanied by maps showing the location of holes drilled and the deposits developed. Each area upon which work was done is reported by half townships. Each bauxite deposit investigated was assigned a name and a number for ready reference and identification, and its location and name are shown on the appropriate half-township map. The description of each half township is followed by a description of each deposit developed in that half township. The 14 half-township maps and 77 detail maps of the bauxite deposits in this series of reports give the locations and numbers of all the holes drilled on the project, except the deep holes drilled to test the geophysical anomalies. The locations of those holes show on figure 13 in volume 1. The description of the deposits developed is followed by complete detailed logs of the drill holes. Many of the widely spaced exploratory holes did not discover bauxite of minable thickness and grade. The pertinent information obtained from the widely spaced exploratory drill holes has been summarized and tabulated and a table for each half township is given with the discussion covering that area.

Jan 1, 1948