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By D. Harrington

During the 5-year period 1906-10 inclusive, 84 major disasters (a major disaster being one in which 5 or more lives are lost) occurred in the coal mines of the United States, or an average of 17 per year, and the total number of fatalities from coal-mine gas and dust explosions (major plus minor) for the 5 years aggregated 2,338 or 477.6 per year. The monotonous continuance of coal-mine disasters month by month aroused the people of the United States to such an extent that it was felt necessary for the Federal Government to try to do something looking to the avoidance of the admittedly excessive loss of life in our coal mines, and this was one of the deciding factors in the establishment of the United States Bureau of Mires in 1910. That results have been obtained in this particular cause of coal-mine accidents may be seen from the fact that for the year 1933 but one major explosion disaster occurred in the coal mines of then united States and the total number killed in that disaster was 7. Unquestionably the coal-mining industry through use of oaf or mining practices and aided by the various kinds of work of the Bureau of Mines looking to the prevention of mine fires and explosions is in large part responsible for this very creditable change. If the gas and dust explosion fatality rate of 1.059 per million tons of coal produced during the period 1906-10 inclusive had continued to the first of January 1934, instead of the 6,373 deaths which actually occurred due to gas and dust explosions, there would have been 13,480. Hence, during the 23 years existence of the Bureau of Mines there has apparently been a saving of about 7,102 probable deaths, or an average of more than 300 per year, from gas and dust explosions as against the number which would have occurred had the 1.059 gas and dust explosion fatality rate for the period 1906-10 continued. Thirty-nine persons were killed in all kinds of explosions (both major and minor) in the coal mines of the United States in 1933; if the 1.059 gas and dust fatality rate of the 1900-10 period had been in effect in 1933, about 400 persons world have been killed. Unquestionably, the various teachings of the U.S. Bureau of Mines looking to the avoidance of explosions and fires in mines have had a vital influence in reducing the number of explosions and fires and also in decreasing their destruction in case they occur.

Jan 1, 1934

By Stephen D. Smith

The following tables summarize data on crude nonfuel mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rico. Although crude mineral production may be measured at any of several stages of extraction and processing, the stage of measurement used in these tables is what is termed "mine output." It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the output from auxiliary processing at or near the mines. Because of inadequacies in the statistics available, some series deviate from the foregoing definition. For copper, gold, lead, silver, tin, and zinc, the quantities are recorded on a mine basis (as the recoverable content of ore sold or treated). However, the values assigned to these quantities are based on the average selling price of refined metal, not the mine value. Mercury is measured as recovered metal and valued at the average New York price for the metal. The values shown are in current dollars, with no adjustments made to compensate for changes in the purchasing power of the dollar.

Jan 1, 1995

By Robert M. Doerr

The research objective was to determine the effect of aluminum alloy additions on the oxidation behavior of cobalt-nickel alloys. Thirty high-purity alloys were reacted with 02 at 0.5 atm at 1,351°, 1,389°, and 1,429° K in a volumetric apparatus for about 300 min. The alloy compositions consisted of Co-Ni master alloys (0, 22, 50, 70, 91, and 100 wt pct Ni) with aluminum additions of about 0, 1, 2, 4, and 8 wt pet. Large early deviations from, or changes in, the parabolic rate constant were encountered, but in most cases, the reaction rate declined approximately in accordance with the parabolic rate law. A sharp peak in the parabolic oxidation rate constant was observed for specimens containing a to 22 percent nickel and 1 to 2 percent aluminum at 1,351° K, and the rate constants for these compositions were lower at the higher temperatures. Specimens containing 8 percent aluminum reacted far more slowly than did any of the others.

Jan 1, 1971

By John Paul Gries

During World. War II, when the curtailment of imports led to an unprecedented demand for domestic mica, beryl, spodumene, and other pegmatite minerals, the Bureau of Mines and the Geological Survey entered upon a program designed to expedite mining of these minerals from the Black Hills area of South Dakota. The program involved napping, sampling, and drilling of many pegmatite dikes in the southern portion of the Black Hills and beneficiation conducted in the field and in the Bureau of Mines laboratories at Rapid City, S. Dak., Rolla, Mo., Salt Lake City, Utah, and College Park, Md. This report describes the occurrence and sampling of the Beecher No. 2 pegmatite, which was investigated as part of the general pegmatite study in South Dakota. Investigation of the Beecher No. 2 pegmatite was started on November 20, 1943, and terminated in the spring of 1944. During this period, the Bureau of Mines took a series of trench samples across the pegmatite at the surface for grain-count studies and chemical analyses. The Geological Survey mapped the geology of the deposit after it was exposed by trenching and stripping.

Jan 1, 1950

By Robert S. Hill

"In November 1942, a preliminary report on the Swartz Mining District by John H. Soule, an engineer of the Bureau of Mines, recommended an exploratory program of diamond drilling. The existence of zinc and lead deposits in this region had been known for many years. In 1943 and 1944, the Federal Geological Survey made a detailed study of the same area. Later work done by the Bureau of Mines in this district followed the suggestions made by these geologists.3/In the latter part of 1944, Felix A. Vogel, Jr., another Bureau engineer, made a study of the Grey Eagle mine in the Kingston Mining District, a few miles northeast of the Swartz district, and his recommendations for diamond drilling were followed in so far as funds permitted. Drilling was started in October 1943 and was completed in June 1945.4/In its program of exploration of Mineral deposits, the .Bureau of Mines 'Ms as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution t national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples of ore and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director.With respect to this report, special acknowledgment for assistance is due to C. H. Johnson, chief of the Rolla Division, Mining Branch, and to various members of the Geological Survey."

Sep 1, 1946

By W. M. Deaton

The Keyes Helium Plant of the Federal Bureau of Mines was constructed under an expedited schedule, to supply the urgent and growing demand for helium in atomic energy, missiles, aerology, space exploration, shielded-arc welding, and low-temperature research. Construction began in December 1958 and ended in August 1959. The plant, near Keyes, Okla., processes 2 percent helium-bearing natural gas from the Keyes gasfield. In 1960 the plant produced and shipped 263 million cubic feet of helium (equivalent to an annual rate of 290 million cubic feet). Production cost was $9.11 a thousand cubic feet of helium. A low-temperature process involving two steps is used; the first separates a crude-helium product from the natural gas at about -250° F. and 225 pounds per square inch gage (p.s.i.g.); and the second purifies the crude helium to a high-purity product (Grade-A helium, 99.995 percent helium) at about -320° F. and 2,750 p.s.i.g.

Jan 1, 1961

By R. D. Wilson

Ten to twelve million tons of dust is produced by cement kilns annu-ally in the United States, resulting in a serious waste disposal problem. The Bureau of Mines investigated two alkali volatilization methods for converting this dust into materials for making portland cement and a useful potassium product. Portland cement kiln dust was found to be composed of finely ground cement raw materials (CaC03 and 8i02) having a layer of alkali sulfate (K2S04 and Na2S04). In this form, it cannot be directly recycled to cement kilns because concrete is weakened by a reaction between the alkali and the aggregate. Portland cements with 28-day strengths above 5,000 psi were produced from low-alkali residues using sintering and melting methods. For nearly complete removal of alkalies, primarily potassium sulfate, from cement kiln dust, a temperature above 1,300° C and a reducing atmosphere were required.

Jan 1, 1986

By Thomas J. Peters

In 1987, at the request of the U.S. Bureau of Land Management, the Bureau of Mines studied the 350-acre Henry?s Lake Wilderness Study Area (ID-035-077) in order to evaluate its identified mineral resources. The Wilderness Study Area is located in northern Fremont County, ID, approximately 140 air miles north-northeast of Pocatello and 3 miles south of the Montana border. The Wilderness Study Area is near the north shore of Henry's Lake at the foot of the southwest-facing slope of Black Mountain. Archean hornblende gneiss, the main rock type present, crops out northeast of the Madison Range Fault, which trends northwest across the southwest corner of the Wilderness Study Area.

Jan 1, 1988

By Richard W. Watson

Card-gap and projectile impact sensitivity data are presented for a wide variety of explosive compositions tested at the Bureau of Mines in more or less standard test geometries. The results of both tests are in good agreement in that they provide the same sensitivity ordering for different subclasses of explosives. Least sensitive were homogeneous liquids that did not exhibit a tendency to undergo low-velocity detonation, ammonium nitrate-fuel oil, and most cast military explosives. Of intermediate sensitivity were pressed and powdered military explosives, cast pentolite, permissible and non- permissible water-based explosives, and one commercial two-component explosive. The most sensitive were permissible and nonpermissible dynamites and explosives susceptible to low-velocity detonation.

Jan 1, 1973

By Wilson Blake

Rock preconditioning in advance of mining was shown to be an effective means of rock-burst control based on the results of a field demonstration carried out on the 7700 level of the Hecla Mining Company's Star mine. Mining through the preconditioned zone was characterized by greatly reduced rates of released seismic energy and no bumping or rock bursting occurred within the preconditioned zone. Mining above the preconditioned zone was characterized by greatly increased rates of released seismic energy and rock bursting, particularly where the vein became very narrow in waste zones. This increased incidence of rock bursting points out the need for stope preconditioning to be carried out on an entire stope block basis. The data obtained from the monitoring of the mining above the preconditioned zone on the 7700 level will be extremely useful in evaluating any future stope block preconditioning experiments on the lower levels or the Star mine.

Jan 1, 1980

By Lester G. Morrell

AGAIN in 1963, as in nearly every year since 1946, the Canadian mineral industry has established a new national record in value of mineral production. The 1963 estimated total value of $2,976 million is 5 percent higher than the 1962 value of $2,845 million.2 As in previous years, metals made up more than half the value of total production. For selected years since 1949 the category percentages and total value are as follows: [ ] Crude petroleum, Canada's most valuable mineral product, accounted for 21 percent of the total value of minerals in 1963. In descending order came nickel 12 percent, iron ore 10 percent, copper 10 percent, gold 5 percent, and uranium 5 percent. Asbestos accounted for 5 percent, sand and gravel 4 percent, and cement 4 percent. The complete list of Canada's mineral products includes more than 50 basic commodities.

Jan 1, 1964

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

"Permissible exposure limits (PELs) have been established for gaseous pollutants, carbon monoxide (CO), carbon dioxide (CO), nitric oxide (NO), nitrogen dioxide (NO2), and some gas-phase hydrocarbons emitted in diesel exhaust. There is, as yet, no PEL recommended for diesel exhaust aerosol (DEA), nor is there a standard method for sampling this aerosol.The University of Minnesota and the U.S. 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 made in underground coal mines that use diesel equipment.The mine mean DEA concentrations for the five mines surveyed, determined with the PDEAS in the haulageway, was 0.89 mg/m3, with a standard deviation of 0.44 mg/m3. DEA contributed 52 % of the respirable aerosol at this location.In three of the mines filter samples were collected for DEA-associated polynuclear aromatic hydrocarbons (PAHs) and biological activity determinations. Two of the mines were also monitored for the major gaseous constituents found in diesel exhaust. In general, the PAH and biological activity levels were similar for all three mines, and indicate that up to 25 % of the haulageway concentrations may be contributed by outby diesel vehicles. Measured concentrations of CO, CO2. NO, NO2, and SO2, were well below regulated levels.INTRODUCTIONDiesel exhaust contains pollutant gases, such as carbon monoxide, carbon dioxide, nitric oxide, nitrogen dioxide, and gas-phase hydrocarbons, as well as DEA. Much of the health-related concern focuses on DEA and associated organic compounds (Watts, 1992a). A wide variety of these PAHs have been identified and some are known carcinogens and/or mutagens. The U.S. Mine Safety and Health Administration (MSHA) has proposed new PELs for these and other contaminants (MSHA, 1989). MSHA has also published an advance notice of proposed rulemaking to establish a separate PEL for diesel particulate (MSHA, 1992)."

Nov 1, 1995

By S. J. Aresco

The Bureau of Mines has been active in promoting the purchase of coal for Government use under specifications that define the requirements in terms of heating value of the coal, expressed in British thermal units, and the composition as shown by proximate analyses. To these, when required, are added the ash-softening temperature, the free-swelling index, and the Hardgrove grindability index. Under most of these specification contracts the bidders guarantee the quality of the coal, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled in accordance with instructions4/ issued by the Bureau of Mines; the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor and, if it is not, a price adjustment is made. Analyses of the delivered coal and tipple samples (samples collected at mine tipples as coal is being loaded into railroad cars or trucks) provide valuable data for use in evaluating future bids. In addition, the continuous .sampling of coal as delivered is a check on the practical results obtained in burning the coal.

Jan 1, 1958

By Lewis M. McNay

The strength characteristics of hydraulic sandfill modified by varying quantities of type III portland cement and two flocculants were investigated by the Bureau of Mines. Three different sand-cement ratios were examined using different percentages of flocculant. Two other experimental variables were curing time and weight-percent solids for hydraulic mixture. Results of unconfined compression tests with strain are discussed. Maximum strength was achieved with 0.5 weight-percent of ferric sulfate per ton of solids when the slurry mixture was 75 weight-percent solids. The bearing capacity of hydraulic sandfill is reduced by increasing the water content and decreasing the amount of cement mixed with sandfill.

Jan 1, 1976

By L. K. Weaver

The objective of this Bureau of Mines publication Is to present a nomograph that provides a fast, convenient method for estimating hydrocarbon lease bonus bids for offshore acreage in the Gulf of Mexico. Discounted cash flow analyses were computed from a model derived to show the costs necessary to explore, acquire, develop, produce, and abandon a 5,000-acre block of offshore acreage, and the estimated income from the sale of the hydrocarbons produced from the block. The range of the variables in the financial analyses used to construct the nomograph are prices of oil, $2.50 to $5.00; recoverable hydrocarbon reserves, 44,651,476 to 127,575,645 barrels; and discounted cash flow (DCF) rates of return, 5.0 to 57.2 percent. A total of 1,234 sets of DCF data were used to construct the nomograph. The range of bonus bids shown on the nomograph is from 2 to 90 million dollars ($400 to $18,000 per acre).

Jan 1, 1973

By N. Kumar Kittusamy

ALTHOUGH MANYSTUDIES HAVE SHOWN an association between operating heavy construction equipment and symptoms of musculoskeletal disorders (MSDs), little research has been performed that systematically characterizes the exposure of operating engineers to ergonomic hazards. This study evaluated: 1) vibration at the seat/operator interface;2) transmissibility of vibration in the Z-axis; 3) psychophysical ratings of vibration level and vibration discomfort; and 4) postural requirements of the job. Results indicate that the digging operation had higher levels of total weighted acceleration than high- or low-idling conditions. Transmissibility data showed that the seat amplified vibration, particularly in the lower frequencies. Seats demonstrated that they may not be sufficient in protecting operators from long-term effects of vibration exposure. High positive correlation was found among subjective ratings (vibration discomfort and vibration level), but moderate positive correlation was found between subjective ratings and quantitative vibration levels. Postural evaluations revealed that the operators were required to assume awkward postures of the neck, shoulder and trunk while performing their jobs. Work-related injuries and illnesses pose a continuing threat to the health and well-being of American workers. The construction industry has been historically recognized as having higher rates of fatality, injury and illness than other industries (McVittie285+; BLS). In 1994, an estimated 218,800 lost-work-day injuries were reported in the construction industry (BLS). Construction also had the second-highest incidence rate for sprains and strains. Although the industry has made progress since then, injuries and illnesses, including MSDs, continue to because for concern.

By Gary R. Peterson

In order to determine the potential availability of alumina to feed U.S. aluminum smellers, the Bureau of Mines evaluated 39 domestic mines and deposits of bauxite, alunite, and high-alumina clays and found that substantial increases in alumina prices would be necessary before nonbauxitic deposits could become competitive with bauxite. As part of the study, a price-tonnage relationship was developed indicating the quantity of alumina that could be produced from known deposits at various alumina prices and at a 15-pct discounted cash flow rate of return on the required capital investment. All capital and operating costs were calculated in August 1980 dollars. The domestic bauxite reserve base comprises three operating bauxite mines in Arkansas containing some 15.6 million metric tons of recoverable alumina (A1203). Ferruginous bauxites, clays, and alunites fall into the subeconomic category of identified aluminum resources, which, at the demonstrated level, contain over 4,000 million metric tons of alumina that are estimated to be recoverable. Analyses indicate that, at the demonstrated resource level, a total of some 15.6 million metric tons of alumina, all from three active Arkansas bauxite mines, is recoverable at a 1980 price of $0.12 per pound ($264 per metric ton) of alumina. A price of approximately $0.26 per pound ($573 per metric ton) of alumina would be required for production of the total U.S. resource. Thus, unless new technological breakthroughs occur that could make alternate sources of alumina competitive with bauxite, U.S. dependence upon imported bauxite will continue to increase.

Jan 1, 1981

By J. M. Mutamansky

"Coal mine dust research throughout the world has been stimulated by the recognition of its importance in the development of coal miners' diseases, particularly coal workers' pneumoconiosis (CWP). A historical look at the problem and the present state of knowledge in this area of importance to the worldwide coal industry is presented. A summary of progress made in this area is provided and some research ideas for the future are discussed.1. INTRODUCTIONI thank Dr. Yong Won John, President of the Korean Institute of Mineral and Mining Engineers, for his invitation to address the International Symposium on Coal Mining and Safety. This presents me with an interesting opportunity to take a broad look at the research in coal mine dust and where we are going. From this broad perspective, we can all view the progress and problems that are apparent in the present state of knowledge of coal mine dust. One important element in the review of coal mine dust research and its role in miners' diseases is that of its history. The existence of diseases attributed to the mine atmosphere is often traced back to Pliny the younger in the first century A.D. His work on natural history mentioned observed human effects attributed to mine fumes and vapors. However, the subject of the effects of dust in the mine was not mentioned in published literature until 1556 when Agricola discussed the ailments of miners in his day (Seaton 1975).For many centuries, many medical ailments of the lungs were often categorized together and distinct diseases were often not recognized until more modern times. The ability to distinguish different lung diseases was limited until the discovery of X-rays in 1986. Nonetheless, Zenker in 1866 applied the term pneumonokoniosis to any disease where dust gathers in the lymphatic depots of the lungs. This term was changed to pneumoconiosis in 1932. While pneumoconiosis was defined in the 1800s, scant attention was paid to control of miners' diseases until recent decades. The first attempt to control disease through control of the mine atmosphere has been attributed to the South Africans who instituted a silica control in 1910 (Drinker and Hatch 1954)."

Jan 1, 1989

By Michael M. Hamilton

In 1985, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied a 37,542-acre portion of the 57,002-acre Riordan?s Well Wilderness Study Area (NV-040-166) in order to evaluate its mineral resources. The area studied is located in Nye County, NV, about 60 miles southwest of Ely, NV. Subeconomic mineral resources of limestone and sand and gravel were identified in the study area. The Troy and Irwin mining districts, 4 miles to the west, were active between 1868 and 1963, producing small amounts of gold, silver, lead, and tungsten from mines well outside the study area. Except for minor prospecting activity, most mining activity in the study area has been since 1980, consisting of claim locations and geochemical surveys.

Jan 1, 1987

By D. H. Carlson, J. H. Johnson

"The U.S. Bureau of Mines and Michigan Technological University (MTU) are collaborating to develop an apparatus for measuring diesel tailpipe emissions in underground mines. A tailpipe emissions measurement apparatus (EMA) is described that dilutes diesel exhaust and measures the concentrations of diesel particulate matter (DPM), CO, CO2, NO, and NO2 at known dilution ratios.The EMA was evaluated by side-by-side comparison of its measurements with those by laboratory grade instruments. Concentrations of CO and C02 measured by the EMA were usually within ± 14 pct of concentrations measured by laboratory-grade instruments for CO and ±20 pct for C02• EMA measured DPM concentrations were, on average, 29 pct lower than those measured by laboratory-grade instruments, with the differences being fairly consistent. The CO and C02 differences are related to the method of calculating the EMA's dilution ratio, and the difference in DPM concentrations is attributed to thermophoretic and/or condensation losses related to the EMA's unheated sample probe. Preliminary analysis of data obtained with a heated sampling probe and modifications in the sampling procedures have indicated reduced variability in DPM and in the calculated dilution ratios."

Mar 1, 1992