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By Thomas J. Peters

This report is part of the U.S. Bureau of Mines Idaho Land Assesment Program to study the mineral resources of priority roadless areas in Idaho. The results of these mineral inventories provide minerals information needed to make wise decisions regarding future land management practices, and to ensure a dependable supply of minerals at a reasonable cost. The 16,300-acre Lionhead area, studied in 1991, lies along the Montana border north of Henrys lake, 10 mi west of West Yellowstone, Montana. The study area includes much of the rugged Henrys Lake Mountains, and is largely covered with conifer forest. Several peaks are over 10,000 ft in elevation. The Lionhead area has been proposed for Wilderness. No mineral resources were identified within or near the Lionhead study area. Five prospects occur in, or within 1 mi of the area: these include 1) an intermittently used road gravel pit, 2) the Thimbleberry lateritic iron prospect, of geologic and historic interest only, 3) the Tick Heaven talc prospect, 4) the Dry Fork garnet prospect, and 5) the lynx prospect, which appears to be of historic interest only. Talc is seen only as float at the Tick Heaven prospect, but the geology is permissive of talc resources at depth. The garnet prospect, and nearby similar alluvial terrane, mainly outside the study area, appears to be the most likely setting to contain mineable resources. Examined workings include four trenches and pits in rock and one gravel pit.

Jan 1, 1992

By D. H. Baker

These investigations were conducted to determine the feasibility of molten salt electrorefining of zirconium scrap, offgrade sponge, and alloys under contract number AT(11-1)-475 between the Atomic Energy Commission and the Federal Bureau of Mines. Offgrade zirconium sponge having a Brinell hardness of 169 can be refined by this technique to produce metal having, consistently, a Brinell hardness of less than 90. Also, zirconium alloy scrap, approximating zircaloy-2 in composition, can be refined to recover zirconium metal with a Brinell hardness of less than 100 that is essentially free of the major alloying elements. Analysis showed that the quantities of these elements were decreased as follows: iron from 0.27 to 0.002, tin from 1.36 to 0.001, nickel from 0.02 to 0.001, and chromium from 0.12 to 0.002 percent.

Jan 1, 1961

By J. F. Barkley

As part of the work of serving as Chairman of Subcommittee 3, Health and Industrial Requirements, of the American Society of Mechanical Engineers' Committee on Air-Pollution Controls, the author assembled the following information on accepted maximum permissible concentrations of air pollutants from the standpoints of health, damage to vegetation, damage to property, and requirements of industrial processes. A search in technical literature was made followed by direct inquiry to all State governments as to their regulations. The subcommittee membership - G. D. Clayton, senior sanitary engineer, Public Health Service, United States Department of Health, Education, and Welfare, Detroit, Mich., Dr. L. Greenburg, commissioner; Department of Air Pollution Control, New York, N.Y., Dr. M. Katz, Defence Research Chemical Laboratories, Ottawa, Ontario, Canada, and Dr. H. H. Schrenk, research director, Industrial Hygiene Foundation of America, Inc., Mellon Institute, Pittsburgh, Pa. - reviewed the information and made very helpful comments and corrections.

Jan 1, 1954

CESIUM metal production increased sharply in 1963. Domestic Production.--Cesium metal was produced by The Dow Chemical Co., Midland, Mich., MSA. Research Corp., Callery, Pa., and by Penn Rare Metals, Inc., Revere, Pa. American Potash & Chemical Corp., Trona, Calif., produced some combined cesium and rubidium. This company, Penn Rare Metals, Inc., and Rocky Mountain Research, Inc., Denver, Colo., produced various cesium compounds. Complete production data on cesium and rubidium and their compounds were not available for publication. Consumption and Uses.-Substantially more pollucite was consumed to produce cesium metal and compounds in 1963 than in 1962 but the overall consumption of pollucite continued to be small.

Jan 1, 1964

By F. W. Wood

Ingots of zirconium and other highly reactive metals such as titanium and hafnium produced by the consumable-electrode arc-melting process require conditioning before forging or rolling. A nondestructive, arc-conditioning technique has been developed as a substitute for lathe conditioning. The technique employs en electric arc under an inert atmosphere to fuse surface metal on the sidewalls of ingots without seriously affecting the general quality of the ingots. Advantages of the practice are Increased yields, lower accumulation of inferior scrap, and actual cost savings. The work cited in this report was done on zirconium. INTRODUCTION The consumable-electrode arc-melting process as practiced at the Bureau of Mines3 4/ has proved to be a technique for producing sound, homogeneous, commercial-size ingots of zirconium and its alloys. Ingots produced by this process, however, have as a characteristic a layer of partly fused metal on the sidewall to a depth of 3/16 to 3/8 inch. To prevent extension of surface imperfections during forging, the ingots are ordinarily conditioned by removing defective material in a lathe. If the metal were less reactive or the requirements less severe, the machine chips could be recycled and remelted. However, zirconium, being so oxygen sensitive, is contaminated by merely being machined despite extensive cooling of the tool bit. Further, being contaminated with oxygen, the chip metal upon remelting is 10 to 25 Brinell-hardnese numbers harder than the ingot from which it was machined. For this reason, the ingot specifications for naval reactor use have prohibited remelting machine chips, except as required for starting pads. Again, were zirconium less costly or less in demand this ever-increasing pile could be burned to oxide and recycled through the Kroll sponge process. Economics do not favor this, as melting feed stock has an estimated increase In value over oxide of about $8.80 per pound of contained zirconium. The efforts of the Bureau to solve the problem have been directed along two lines: To reduce the contamination of the machine chips produced and to reduce the quantity of the chips produced. This paper presents the technique developed to reduce the quantity of chips produced by arc-conditioning the remelted ingot.

Jan 1, 1955

By B. D. Hanson

The U.S. Bureau of Mines has developed an interactive computer program which enables the user to identify the effect of cutting system changes on relative dust generation and forces for continuous miner drums. The program simultaneously evaluates machine and coal seam parameters, and those parameters which the user can control. One or more of these parameters may be changed to determine their individual or collective effect on relative dust generation and cutting forces. The program is written in the BASIC programming language. A complete program listing is included along with user instructions and sample outputs.

Jan 1, 1989

By T. E. Gray

This report describes the preparation characteristics of the more significant coal beds in Allegheny County, Pa. It is one of a series planned to determine coals suitable for producing metallurgical coke, either as mined or after beneficiation. More than 7 million tons of coal was produced in Allegheny County in 1957. Of this, more than 5 million tons was cleaned mechanically in nine cleaning plants. The Bureau of Mines estimated that, as of January 1, 1953, more than 384 million tons of recoverable coal remained in the county in beds 28 inches or thicker.

Jan 1, 1959

By Berenice B. Mitchell

THE STATISTICAL tables in this chapter present, country by country, the mineral production of the world in 1949-50. The figures are on a mine basis, unless otherwise indicated, except for cement, coke, and steel, which are measured at the processing plant. The tables are essentially a retabulation, by countries, of the 53 commodity world tables appearing in the various chapters of this volume. For lack of comprehensive information, data for the following minerals are excluded: Andalusite, aplite, asphalt, boron, bromine, calcite (optical), calcium chloride (natural), carbon dioxide, clay, columbium (niobium), diatomite (kieselguhr), dumortierite, emery, garnet (abrasive), gem stones (other than diamonds), germanium, greensand, grindstones, helium, indium, iodine, kyanite, lithium, magnesium compounds (other than magnesite), meerschaum, mineral pigments, monazite, natural gas, natural gasoline, oil shale, olivine, perlite, pumice, quartz crystal, radium, sand and gravel, selenium, sillimanite, sodium salts (other than common salt), stone, strontium, sulfur (byproduct), tantalum, tellurium, thallium, topaz (industrial), tripoli) uranium, vermiculite, wollastonite, and zirconium. In addition, a few minor geographic areas for which no statistics are available, are also omitted from the tabulation; it is believed that no significant quantities of minerals are mined in any of these areas. The statistics in these tables were derived principally from questionnaires sent, in cooperation with the United States Department of State, to the governments of each country. Supplementary sources were United States consular reports, the Imperial Institute's Statistical Summary of the Mineral Industry of the British Commonwealth and Foreign Countries, other official publications of various countries, the United Nations Statistical Yearbook, the Year Book of the American Bureau of Metal Statistics, Minerais et Metaux, business magazines, and company reports. Where official data were not available, esti-

Jan 1, 1953

By A. E. Wells

"When the United States entered the World War, the heavy requirements for sulphuric acid in the manufacture of explosives made necessary a definite knowledge of the sulphuric acid capacity of the country. The Bureau of Mines, under the authority conferred by the explosives regulation act, made a thorough survey of the sulphuric acid situation. In this work, which was personally directed by the writer, comprehensive data were collected on the situation and capacities of the various acid plants, sources of supply of raw materials (brimstone, pyrite, pyrrohotite, zinc ores and concentrates, waste sulphur dioxide gases from copper smelting, and spent oxide from gas works), the principal points in regard to manufacturing processes (chamber and contact) and the uses of the acid. The results of this investigaion have recently been published by the Bureau of Mines, as Bulletin 184, entitled ""The Manufacture of Sulphuric Acid in the United States"" by A. E. Wells and D. E. Fogg. The following paragraphs on the uses of sulphuric acid are abstracted from this bulletin.Sulphuric acid is one of the most important of all chemicals, not only because of the large quantities manufactured but also because of the wide use of the acid in many different industrial works. Sulphuric acid is to the chemical industry what iron is to metallurgy. The general public, however, does not realize this fact, for sulphuric acid does not appear in the finished product as does iron and steel, but is only a means to an end. It is essential in many industries, such for example as in the manufacture of phosphate fertilizers, explosives, dyes and petroleum products. In recent years in the United States, especially in the East, the demand for sulphuric acid for chemical and metallurgical industries has been an accurate and sensitive barometer of the general business conditions. This demand for acid responds much more quickly to a general slump or boom in the industrial world than does the demand for iron and steel."

Oct 1, 1920

By John C. Edwards

A two-dimensional, time-dependent, mathematical model has been developed that describes fire spread along the walls of a ventilated duct. The model is based on the assumption that the leading edge of the fire zone propagating along the wall surface coincides with the isotherm for the fuel ignition temperature. The model includes gas-phase energy transport via radiation and forced convection inside the duct and solid-phase energy transport by conduction into the fuel lining. Product gases emitted from the fire zone are assumed to mix uniformly with the ventilation gas to produce an optically dense gas mixture at the combustion temperature that enters the preheat region. Numerical solutions of the model equations for a coal-lined duct (simulated coal mine entry) have been used to investigate the effects of tube radius, air velocity, combustion temperature, and optical density of the soot-laden gas upon the terminal fire spread rate.

Jan 1, 1977

By G. W. Jones, R. E. Kennedy

A simple , quick, and relatively accurate device is needed for determining the presence of very small concentrations of organic halide gases in various atmospheres . Such a device would enable safety engineers , health officials , and others to discover quickly the presence of these gases in a suspected atmosphere and thus be able to apply protective measures promptly. This detector should prove useful in detecting leakage of halide gases from refrigerating and air - conditioning systems and in determining the presence of halide solvents in the atmosphere of dry - cleaning and degreasing establishments where organic halide solvents are used . Virtually all poison war gases are halide compounds . Because of the high toxicity of these gases , even in very low concentrations , a detector having the proper sensitivity should be useful in civilian defense for determining when atmospheres are relatively free of poison gases .

Apr 1, 1943

By Joseph Cervik, J. H. Perkins

The Bureau of Mines has conducted desorption work on fine coal particles at near atmospheric pressure. An apparatus has been developed that uses a capacitance manometer to measure desorption of methane from coal particles up to 2 inches in diameter and pressures up to 1,000 psi. This will make it possible to duplicate the desorption process as it occurs in its natural under- ground environment.

Aug 1, 1970

By E. H. Denny

The coal and metal mines of the United States furnish this country with a large part of the fuel and material necessary to support our industries and thus make possible the welfare and prosperity of our people and even the continuance of our present-day scale of civilization. Mining companies furnish material to industry with one general purpose in mind -- the making of a profit on their work. Efforts are being made successfully and continually to reduce operating costs, to increase production per man, and to perform work as far as possible mechanically and with more efficiency. These efforts are made primarily to reduce costs, to increase production, or to do both - in other words to make more profits or more certain profits. In the endeavor to reduce expense companies are considering more and more the factors which enter into costs of production, among them the factor of accidents and their cost. This paper endeavors to estimate the approximate cost of accidents to the mining industry in order to present the saving possible through accident reduction or elimination.

Jan 1, 1929

By K. D. Luxbacher

Understanding methane emissions in underground coal mines is critical for a safe and productive mine. In addition to reasonable estimation of initial coalbed reservoir parameters, it is also crucial that changes in effective stress due to mining and pore pressure reduction are taken into account due to their effects on porosity and permeability. Primary parameters for estimation of emissions or modeling of the mining environment for this purpose are porosity and permeability which can change dramatically as a result of stress redistribution associated with mining and gas desorption from a large coal volume. These parameters affect the emission rates and ventilation requirements, as well as water inflow into the working environment. Stopping leakage, on the other hand, is a secondary stress dependent factor in estimation of emissions, as convergence of the roof and floor strata, compromising the integrity of the stopping, may result in leakage, making prediction of ventilation requirements difficult. This paper aims to examine the effects of porosity and permeability changes of the coal seam on methane emissions in an underground continuous miner section. The models were developed and executed in a dynamic fashion to simulate an advancing section. Through this process, the changes of effective stress in coal, particularly their change paths, on porosity and permeability were incorporated into the models and methane emissions, concentrations, air requirements, water inflow and possible leakage from the stoppings were investigated using a conventional coalbed methane reservoir model.

Jan 1, 2009

By D. E. Hirsch

The types of compounds present in aromatic concentrates derived from high-boiling petroleum distillates can be estimated from a gel permeation chromato-graphic (GPC) analysis by the use of tables developed from extensive GPC and mass-spectral analyses on fractions from four crude oils. For a fraction from the GPC analysis, the retention volume and the molecular weights (from mass spectrometer) suffice to indicate the types of compounds which predominate. The tables which show these qualitative analyses were developed through the use of pure compounds as well as the extensive analyses on Prudhoe Bay (Alaska), Gach Saran (Iran), Swan Hills (Canada), and Wilmington (California) crude oils. These tables provide a rapid method for determining which types of compounds are present in a GPC fraction before attempting to develop quantitative data.

Jan 1, 1974

By G. R. Hopkins

"A new record in fuel efficiency at petroleum refineries was achieved in 1935, when an average of only 615,000 B. t. u. was needed to refine a barrel of crude oil, compared with an average of 638,000 B. t. u. in 1934 and 829,000 B. t. u. In 1925. (See fig. 1.)Refiners have made almost uninterrupted progress in firing efficiency during the last decade although much of this gain was brought about by improved technique and greater use of heat exchangers and pipe stills, the determining factor was the trend in crude runs to stills. Most plants can increase their crude throughput materially with but small increase in fuel consumption. Consequently, in years in which crude runs have increased substantially, average requirements have declined; but in years in which crude runs have decreased, the average has tended upward. This conclusion is confirmed by figure 1, which shows that there has been but one minor exception to this rule in the last 10 years.Technical progress in fuel efficiency may be illustrated by comparing crude runs and total B. t, u. consumed. Between 1925 and 1935 crude runs to stills increased 31 percent, but the total quantity of heat required did not increase; in fact, it declined slightly.The trend of modern still construction is from shell stills, in which a large body of oil is heated, to tube stills, in which the heat comes into much closer contact with the oil. In 1935 the total capacity of operating pipe stills increased about 4 percent; this increase, though small, probably was related to the gain in average efficiency.The Increased use of heat exchangers and their role as fuel savers have been discussed in previous reports of this series. It is sufficient to say that refiners with insufficient exchange capacity added as much in 1935 as their budgets would permit."

Jan 1, 1937

By Maria I. De Rosa

This report analyzes mine fires for all U.S. underground and surface coal mining categories by state and2-year time periods during 1990–1999. Risk rate values are derived, and ignition source, methods of fire detection and suppression, and other variables are examined. The data were derived from Mine Safety and Health Administration (MSHA) mine fire accident publications and verbal communications with mine personnel. The analysis will provide the National Institute for Occupational Safety and Health, MSHA, and the mining industry with a better understanding of the causes and hazards associated with mine fires and will form a basis for future fire research programs.

Jan 9, 2004

By George S. Koch

A statistical analysis of silver assay data from rotary-drill-hole cut-tings and diamond-drill-hole cores from the Round Mountain prospect, Custer County, Colo., demonstrates several useful methods for estimating grades and tonnages of ore from the drilling of wide-spaced holes in disseminated deposits of precious metals. A new method of are appraisal is introduced which estimates grade and tonnage of are by calculating convex hulls (smallest convex polygons) for sample points with assay values above specified cutoff grades. Analyses of variance compare the consistency of data from rotary-and diamond-drill holes, from rotary-drill holes sampled at 2-and 4-foot intervals, from two methods of sample preparation, and from atomic-absorption and fire assaying. Evidently, data from the two types of drill holes, from holes sampled at the two intervals, and from different methods of preparation are in agreement. Atomic-absorption silver values are consistently lower than fire-assay silver values.

Jan 1, 1971

By Rudolf E. Greuer, Linneas W. Laage, Xinton Chang

MFIRE is useful for the analysis of ventilation networks under thermal and mechanical influence MFIRE simu¬lates a mine&apos;s ventilation system and its response to altered ventilation parameters, external influences, and internal influences Extensive output enables detailed quantitative analysis of the effects of the proposed alteration on the ventilation system MFIRE was written in FORTRAN 77 and compiled with Microsoft° FORTRAN for the Intel 8086-8088 central processing units The source code is listed in appendix A for users who wish to modify the source code for operation on other computers MFIRE MODIFICATIONS OF MTU-BOM CODE The program described in Bureau of Mines Informa¬tion Circular 8901 has become known as the MTU-BOM codes MFIRE is an evolutionary product of the MTU¬BOM code with major improvements and enhancements 6 For users previously familiar with the MTU-BOM code, the following is a listing of the major improvements and enhancements incorporated by MFIRE 1 The length of an airway is an input value, LA The elevation difference of the airway is calculated from the elevation input, Z, in both programs It is possible for a data file to describe an airway that is shorter than its el¬evation difference The MTU-BOM code does not check for this error and uses the values of LA and Z This does not cause a computational problem, only a simulation problem MFIRE issues a warning message for this case, and the airway length is made equal to the elevation dif¬ference if LA is less than Z 2 To evaluate rock temperatures (average wall surface temperature of airway before a fire), it is assumed that the air temperature at an airway entrance is equal to the air temperature at the airway starting junction, and that the air temperature at the airway exit is equal to the air tem¬perature at the exit junction. The MTU-BOM code follows this assumption in all cases When a rock temperature of less than 0° F is calculated, an average temperature is used to represent the rock temperature of the airway MFIRE uses the same principle, except the consideration of unlikely rock temperatures When the exit junction of an airway is the atmosphere (a fixed condition junction), the air tempera¬ture at the exit is made equal to the air temperature at the airway beginning If an unlikely value of wall temperature (<0° F or > 150° F) results from calculations, a message is issued and the rock temperature is set equal to the air temperature at the airway exit The program user can always input rock temperature (TROCK) for an airway to override the calculated value. 3 MFIRE allows use of an optional reference airflow rate to define and limit the heat generation of a fire source This allows the simulation model to more closely resemble a real fire and to improve simulation conver¬gence Heat generation corresponds, but is not linearly related to airflow rates reaching the fire In the simula¬tion, heat generation is calculated from oxygen consump¬tion and is directly related to the variable incoming airflow Use of this optional reference airflow rate allows the heat generation to vary, but in a damped, user defined manner When the airflow rate passing through a fire source is equal to its reference airflow rate, the data items describ¬ing the fire source are not modified If the airflow rate is lower or higher than its reference airflow rate, the data items used to define the fire source are modified according to the following equations

Jan 1, 1990

This chapter describes the adverse health effects associated with exposure to respirable coal mine dust. Epidemiological studies of underground and surface coal miners in the United States and other countries are discussed. Also discussed are animal studies that add to our understanding of particle deposition and retention in the lungs and associated disease responses. This chapter emphasizes studies that (1) were performed since the passage of the Federal Coal Mine Health and Safety Act of 1969 [P.L. 91- 173], (2) used standardized methods of exposure monitoring and disease classification, and (3) investigated exposure-response relationships between respirable coal mine dust exposure and disease. Several published review articles contain further discussion of health effects studies of coal miners [Attfield and Wagner 1992b; Petsonk and Attfield 1994; Cotes and Steel 1987; Merchant et al. 1986; Morgan and Lapp 1976; Morgan 1975].

Jan 1, 1997