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By W. S. Wright

"INTRODUCTION The Ward copper deposit was brought to the attention of the Bureau of Mines in September 1943 by John J. Knob, 217 E. Penn Street, Long Beach, N. Y. At that time all Bureau of Mines work on Seward Peninsula was being directed to the exploration of deposits of tin, a metal high on the strategic list. It was not until September 1946 that the Bureau could make a preliminary examination of the Ward prospect.ACKNOWLEDGMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual investigative work, and prepares the final report. The Metallurgical Branch, Oliver C. Ralston, chief, analyzes samples and performs beneficiation tests.Acknowledgment is extended to Robert S. Sanford, acting chief of the Alaska division, under whose supervision all exploratory work of the Territory is conducted."

Aug 1, 1947

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

C.5 Safety Equipment and Control Devices Safety equipment and control devices serve two principal functions in mine escape hoists. First, they can be used to provide important safety features such as protection against overspeed, over¬travel and undertravel. Second they can be used to automate or partially automate the operation of the escape hoist. Typical equipment available is described in the following section. 1. Simplex and Lilly Hoist Controllers Manufacturers: Logan Actuator Co. 4956 No. Elston Ave. Chicago, Illinois 60630 312-736-7500 The Simplex and Lilly Controllers provide a means for electrically shutting off the power to the hoist and the energy to physically set the brakes in the event of overspeed, overtravel, undertravel and failure to begin deceleration within sufficient distance

Jan 1, 1976

The first steps in the process of mine evacuation are the recognition of a problem and an attempt to communicate the problem to miners who may be affected. This chapter will focus on the way that a problem, fire, came to the attention of mine personnel and the messages that were sent to miners in the affected areas. The concept of information uncertainty, which was introduced in chapter 4, will be discussed as it influences problem perception and diagnosis. Sociotechnical and interpersonal communications will be explored and suggestions for improving these systems will be offered. It might seem that the first indication of a dangerous fire would motivate individuals to take self-protective action, to evacuate the affected area or structure, and to provide clear warning to others who are in danger. Research has actually shown that in most situations this does not occur. Instead, time is taken to gather more information, confirm information that is provided, and consider possible alternative explanations that could account for the given circumstances [Canter 1990; Scanlon 1979; Bickman et al. 1977]. This process of confirmation can lead to the loss of critical time. Canter [1990] summarizes the problem in his book, which reports studies of a number of fire events: "As discussed throughout this book, ambiguity and confusion, incoherent instructions and time-wasting actions, lack of appropriate instructions and misunderstanding of the nature of the event that is unfolding, are all hallmarks of fires and emergencies that kill people." In this chapter, the detection of each mine fire and the communication of warning to endangered miners will be reviewed with an emphasis on how those processes were affected by the availability and use of information. Information can become available through a variety of mechanisms during an emergency situation. First, cues may be taken directly from the environment. Smoke is an obvious example. Secondly, mechanical devices, such as smoke detectors, may provide warning messages. A third source of information is interpersonal communications. These can occur face-to-face or through some mechanical device such as a telephone. With all three methods there is a possibility of miscommunication, misunderstanding, and misinterpretation. All of these means of communication were used with varying degrees of success in the three mine fires analyzed here. A fire, like any nonroutine situation, engenders uncertainty about a diagnosis and understanding of the problem [Mead 1938]. This uncertainty leads to delays in realization of the seriousness of the situation and therefore in the proper response to it. Delay in action is an important concern in any fire setting, but is even more at issue in underground coal mine fires. Mine fires are qualitatively different from structural blazes: workers' escapeways may be miles long; the seam height at many operations is so low that it is impossible to walk upright; access to underground workings is always limited to a few (sometimes only two)

Jan 1, 2000

By Forrest T. Moyer

The safety record of the mineral and mineral-fuel mining and processing industries in 1965 was improved slightly, as indicated by the reduced injury-frequency and severity rates. The overall operating activity was higher in 1965 as measured by the gains in the number of men working and in the total man-hours of worktime. Injury Experience.-The rate of occurrence of all disabling work injuries in the mineral industries was 17.65 per million man-hours in 1965. This overall rate comprised frequencies of 0.28 for fatal and 17.37 for nonfatal work injuries, of which both were slightly better than the corresponding rates of 0.29 and 17.53 in 1964. Fatalities totaled 537; 5 less than in 1964. However, the total of 32,982 nonfatal injuries was 575 higher than in 1964. This larger number of nonfatal disabilities was offset by the increased worktime so that the nonfatal frequency rate decreased in 1965.

Jan 1, 1967

Homans [1950] offered a working definition of group that is useful for this research: "We mean by a group a number of persons who communicate with one another often over a span of time, and who are few enough so that each person is able to communicate with all the others, not at secondhand, through other people, but face-to-face." This chapter begins with a discussion of the group concept in reference to the hypothesized escape groups mentioned earlier. It then moves to an examination of analysis techniques used by the authors. Finally, the subjects themselves are profiled according to their demographic characteristics. The Nature of Groups Warriner [1956] took a realist approach to understanding groups: "(1) the group is just as real as the person, but (2) both are abstract, analytical units, not concrete entities, and (3) the group is understandable and explicable solely in terms of distinctly social processes and factors, not by reference to individual psychology." Warriner's realist position merely holds that "group" occupies a different domain in which it is no more or less concrete than "person." At this group level the unit of analysis will be those relations that indicate social rather than individual behavior. It is possible to investigate these group properties empirically-if a researcher avoids confusing conceptual entities with concrete ones. Most people seem to accept that group attributes must somehow be inferred, but think personal attributes will be directly manifested, requiring little or no interpretation [Snizek 1979]. In other words, nobody would equate physical components of an underground working section with the actual work group, yet social scientists (as well as laypeople) very often confuse real individuals with notions of the person. In actuality, neither groups nor persons are directly disclosed to the senses; both are inferred by experience and observation. One can "see" a group just as clearly as one can "see" a person, given the proper perspective from which to do so. It is necessary, in developing this perspective, to begin with a sound definition of the thing being examined. Besides communication, or more generally, social interaction, Homans [1950] included three other components of group makeup. "Sentiment" is characterized as the feelings people tend to form about one another when they interact often. These feelings include not only friendliness and dislike, but attitudes such as approval or disapproval. A "norm" is an idea, held in common by group members, that specifies how people ought to behave in given circumstances. In lay terms, norms are simply those informal rules individuals abide by in order to get along together in social situations. Finally, "activity" refers to those things persons do with others. In work groups, as an example, many of the activities are cooperative and goal-directed.

Jan 1, 2000

By T. Estelle Gardner

The Bureau of Mines made enthalpy measurements on sodium bromide and sodium iodide in the temperature range 400° to 1,200° K using an ice calorimeter. Equations representing enthalpy as a function of temperature were derived from the data by the method of least squares. These equations were used to calculate smooth values of heat capacity, enthalpy, and entropy at 50° K intervals from the ice point to 1,200° K. The melting point determined for sodium bromide was 1,020° K; the melting point of sodium iodide was 934° K. The heats of fusion of sodium bromide and sodium iodide were calculated to be 6,270 and 5,680 cal/mole, respectively.

Jan 1, 1967

By N. S. Dalal, B. Jafari, V. Vallyathan

Electron spin resonance measurements have now been completed on the decay kinetics of the organic free radicals formed on crushing or grinding of a well characterized anthracite coal. The free radicals exhibit a complex decay pattern for the first few hours after the grinding, and a smooth decay thereafter. Parallel hemolysis studies indicate. a half-life of the decrease in the cytotoxicity of the fresh· dust to be about half-a-day. The cytotoxicity of the freshly-made dust decreases on addition of superoxide dismutase, catalase and sodium benzoate. The hemolysis rate is lower for the dust stored in buffers as compared to air. A chemical model will be presented to accomodate the cytotoxicity and spectroscopic data, and ~heir implicati6ns to pneumoconiosis.

Jan 1, 1988

By M. L. Odenbaugh

The viscosity reduction effect of varied concentrations of leonardite (a naturally oxidized form of lignite) and leonardite-caustic on the rheological properties of a standard bentonite drilling fluid was studied and evaluated. The minimum plastic viscosity was found to occur at application rates of 4 lb of leonardite and 1.33 lb of caustic per barrel of drilling fluid. Leonardite-caustic treatment was not beneficial in treatment of salt-contaminated drilling fluids. Although filter loss rate was reduced; both yield values and gel strength were increased. Compared with other viscosity control agents) including quebracho) ligno-sulfonate) humic acids extracted from leonardite) as well as other reaction products of lignite) leonardite is less effective at low application rates but is an effective treating agent at rates of 2 Ib/bbl or more. Considering the comparable merits of the substance tested) the major factor in determining which agent to use should be based on cost consideration.

Jan 1, 1967

Table 1.-Employment and injury experience at metal mines in the United States, by industry groups [ ]

Jan 1, 1967

By R. V. Ramani, P. M. T. White, D. Sutton

This review of literature is centered around ore evaluation and reserve calculations as generally used in the mining industry. Methods of data interpolation were reviewed with the object of determining a method that would best suit the evaluation of under- ground coal deposits. Further, computerized data library concepts as related to geological data were investigated together with a brief evaluation of the data requirements for the total project. Additionally, computer techniques for the processing of geological data with a view to generate management information for decision making were reviewed including hardware and software availability. 2.1 Interpolation and Extrapolation of Data The importance of accurate estimates of value parameters in terms of their geographical and geological distribution within a, mineralized body has long been recognized in the evaluation of metallic and non-metallic deposits. As the factors which affect mineral distributions and associations are better understood, accuracy, and reliability of estimation increases. The ideal objective is to develop a deterministic model with the capability of accurately predicting the value at any geographical location. The most important value parameters requiring determination in any orebody are the grade and the quantity of ore that can be mined at the stated grade. These two parameters are modified or qualified by others which include physical dimensions and physical and chemical characteristics of the ore value. Therefore, the

Jan 1, 1974

By S. H. Katz

"At the annual meeting of the International Association of Fire Engineers at Kansas City, Mo., in June, 1919, the Bureau of Mines offered to cooperate with municipal fire departments for the purpose of obtaining information regarding composition of the air in burning buildings. (Katz, S. H., Statement made at Convention of International Assoc. of Fire Engineers: Fire and Water Eng., vol. 66, July 16, 1919, pp. 129-30, also Fireman's Herald, vol. 78, July 12, 1919, pp. 48.) The gas-mask laboratory of the Bureau's experiment station at Pittsburgh sent vacuum bottles for taking samples to fire chiefs in twenty-five cities, who had signified their intention to aid in this work. It was hoped to obtain one hundred or more samples, because statistics in quantity are necessary for drawing reliable conclusions concern-in the likelihoods of encountering irrespirable as in burning buildings. This far, eleven samples have been received by the laboratory. Results of analyses and pertinent data regarding these samples are given in the accompanyingEight of the eleven samples contained, no carbon monoxide; seven of the eight were taken above the ground level and one below ground. One sample taken above ground contained 0.03 per cent carbon monoxide, and this quantity is not dangerous to breathe for a limited time. Of the three samples taken below ground, one contained no carbon monoxide; the other two contained 0.10 and, 0.35 per cent, respectively. This indicates that in a burning building, the hazard from carbon monoxide is much greater below the ground level. The cause undoubtedly lies in the poorer ventilation that is usually found in cellars or basements. Abundance of ventilation provides the necessary air for complete combustion, or if incomplete combustion does occur, the carbon monoxide generated by the fire is greatly diluted with fresh air and swept away by the current. It may be noted that the highest proportion of carbon monoxide was found in a cellar where a fire as burning among piled cases. The difficult access of air to the burning parts facilitated the formation and lib ration of carbon monoxide. The smoke here was very light and no difficulty was experienced in breathing. Some of the air containing dense smoke showed little change from normal air by analysis. Thus the density of smoke or the irritation and difficulty it causes in breathing are no indication of the presence of poisonous gas. None of the samples shows important oxygen."

Nov 1, 1920

To develop an in-mine water treatment system in which bacterial sulfate reduction and limestone dissolution continuously remove metals and acidity from contaminated drainage. Approach A section of mine tunnel was converted into a water treatment bioreactor by constructing cinder block dams and fang the area between them with a porous substrate mixture of limestone gravel and compost. Readily fermentable materials such as dairy whey, spent brewing yeast, or sugar were periodically added to the reactor. Mine drainage was impounded behind one of the dams and continuously percolates through the reactor substrate at a controlled rate. How It Works The reactor substrate soon becomes anaerobic after it is saturated with mine water. Under anaerobic conditions, sulfate-reducing bacteria consume the organic materials that are added to the reactor and generate hydrogen sulfide (HIS) and alkalinity. The H2S reacts with dissolved iron and heavy metals to form metal sulfide precipitates. The alkalinity raises the pH of the water and induces aluminum to hydrolyze and precipitate as aluminum hydroxide [Al(OH)3]. Additional alkalinity is generated by the continuous dissolution of the substrate limestone. Metal sulfide precipitates and Al(OH)3 are retained within the reactor, and the treated water is discharged. The underground location of the system allows year round operation.

Jan 1, 1994

By Henry Kreisinger, WALTER T. RAY

The investigation of the transmission of heat into steam boilers is one of several researches now being carried on by the Bureau of Mines that have for their object the testing of methods by which the mineral fuels in this country may be used more efficiently. A better understanding of the laws governing heat transmission into boilers will result in the design of more efficient boilers, and more efficient boilers will reduce waste in the use of fuel. The results of the investigations described in this report indicate that the conductivity of the heating plates of steam boilers is so high that the present steaming capacities can be tripled or quadrupled by forcing over the heating surfaces three or four times the weight of gases now passed over them. With well-designed mechanical-draft apparatus this greater weight of gases can be forced through the boilers at a small operating cost. It is possible to increase the capacity of many of the present boilers in this way without reducing their efficiency much; in fact by a proper arrangement of the heating surfaces the efficiency can be made higher than the present rating. The efficiency of any boiler can be increased by arranging its heating surfaces in series with respect to the path of hot gases. New boilers of high efficiency can be constructed by making the cross section of the gas passages small in comparison with the length. In Bryan Donkin's book, entitled "The Practical Physics of the Modern Steam Boiler," it is stated that James Watt obtained nearly as good an evaporation per pound of coal and per square foot of heating surface as is obtained now. The remark is probably true. At any rate, about the only decided superiority of the modern steam boilers over older types is in mechanical construction, and for this superiority credit should be given to the designers of machine tools quite as much as to the boiler engineer. The main reason for tardi- ness in boiler improvement probably lies in the reluctance of educated engineers to do the dirty and disagreeable work involved in boiler tests.

Jan 1, 1912

By Franklin D. Cooper

This chapter includes tables for 1979 that were not available in time for publication in the 1978-79 Minerals Yearbook, but it does not include corresponding tables for 1980. The value of raw nonfuel mineral output in 1980 was estimated at $24.8 billion, 8.5% above the 1979 value. Of the 21 metal commodities produced, quantitative output increased for 11 and decreased for 10. The values for 10 metals were up, 10 were down, and 1 was unchanged. Among the 47 non-metallic commodities produced, 14 showed quantitative increases, 32 declined, and 1 was unchanged. In terms of value, 32 nonmetallics increased, and 15 declined.

Jan 1, 1981

By Edward Thimons, William A. Hertbrink

The effect of wind speed upon aerosol penetration into an idealized enclosure was studied The idealized enclosure was a painted plywood box that was 1 2X1 2 XI meters in volume Two fans supplied 1 7 m3 /min of filtered air to this enclosure at a static pressure of 2 8 mm of water The enclosure had a 7 5 cm diameter vent port which was isolated from the air flow around the enclosure To simulate holes in real enclosures, three 16-cm diameter holes were drilled on the front and back sides of the enclosure This simulated enclosure was placed in a tunnel-like structure The air flow from an ultra-light air craft was directed at the front of the enclosure The air speeds were varied between 14 and 36 km/hr as measured by rotating vane anemometer Static pressure in the enclosure was measured with an electronic manometer Two optical particle counters measured the particle number concentration of particles between the 0 35 to 0 5 µm inside and outside of the enclosure Aerosol penetration into the enclosure was computed as the ratio of the aerosol concentration inside the enclosure to the concentration outside of the enclosure The enclosure static pressures measured increase from 2 8 to 3 4 mm of water (P=00001) Aerosol penetration into the enclosure increased linearly with air velocity above 20 km/hr Theoretically estimated penetrations were correlated with observed penetration into the simulated enclosure When simple linear regression was used to model the observed penetration as a function of the estimated penetration, the value of the slope was 0 69±0 12 and the P value for the regression model was less than 0 0001 These results indicate that enclosure static pressure needs to be higher than the wind's velocity pressure in order to minimize aerosol penetration into these enclosures

Jan 1, 1999

By R. K. Koch

In seeking substitutes for such critical metals as chromium, cobalt, and nickel, the Bureau of Mines investigated techniques for shape-casting titanium in rammed sand molds. Castings were made in olivine, garnet, chromite, and, for comparison, zircon. It was found that commercial-grade castings up to 31 lb (maximum capacity of furnace) could be made in zircon or olivine molds if a zirconia mold wash was used. Castings up to 4 lb could be made in chromite molds, but heavier castings suffered from some mold-metal reaction. Garnet molds were found to be unsatisfactory for castings of all sizes because of gas blows and rough surfaces. In other tests shell castings of acceptable quality were produced in water-glass-bonded zircon and olivine molds up to weights of 8 lb, but chromite molds were unsatisfactory because rough casting surfaces were caused by mold-metal reaction. Unlike the currently used commercial processes, neither the rammed-sand nor the shell-molding processes developed by the Bureau of Mines generate noxious fumes at any step.

Jan 1, 1980

By Lawrence L. Davis

This chapter includes tables for 1981 that were not available in time for publication of the 1981 Minerals Yearbook, but does not include corresponding tables for 1982. The value of raw nonfuel minerals produced in the United States during 1982 was estimated at about $20 billion, a decrease of $5 billion compared with that of 1981. The decline in value is the first since 1971 and is the largest percentage drop since 1938. Although the domestic mining industry continued to be troubled by difficulties in attracting capital and by import competition from countries with lower overall production costs, the principal cause of the decline was sharply decreased demand brought on by the worldwide economic slowdown. Metal commodities were impacted most severely with only 4 of 21 metals registering production value gains and only 3 of 21 showing production quantity increases. Overall metal production value decreased 37% from that of 1981, a reflection of the domestic slowdown in the automobile and construction industries, which are major metal users, Overall production value of nonmetals decreased 12% compared with that of 1981, with only 14 out of 44 nonmetals showing increases. Nonmetal production quantities increased over 1981 for only 6 of the 44 nonmetals.

Jan 1, 1983

By George J. Carter, George H. Todd, Hal J. Kelly

In July 1956, the Bureau of Mines and the J. R. Simplot Co. participated in evaluating and beneficiating drill-hole samples from the Bovill, Idaho, clay-silica deposit and in tests of the beneficiated products. The geology, mineralogy, beneficiation, and potential uses of the clay and quartz fractions of the Bovill deposit are described. Test work showed that a filler-grade clay having an apparent spectral reflectance of 78 percent can be made by bleaching, and by removing some of the submicron-size particles. A quartz product suitable for the manufacture of glass containers can also be made.

Dec 1, 1963

By William G. Gruzenaky

The separation of yttrium and the individual rare-earth elements (lanthanons) from mixtures in which they occur has been a difficult problem through-out the years. Because of the increased interest in the various uses of these metals, the economy of their production may become of great importance. Studies relative to this problem, undertaken at the Federal Bureau of Mines Albany Metallurgy Research Center, resulted in the development of a solvent extraction method by which yttrium can be separated from the rare-earth metals. A separation factor of 10.93 was obtained between yttrium and cerium from a single-stage extraction, and a factor of 1.78 was obtained between yttrium and erbium from a multistage system. The valuable metals were extracted from euxenite by caustic soda fusion or by chlorination, and several separation methods were investigated. Partial separation of the yttrium and rare-earth element fraction was made by chemical methods and by solvent extraction. Thermal decomposition of aqueous rare-earth nitrates or selective ignition of yttrium and rare-earth oxalates yielded a fraction enriched in cerium. A fraction enriched in the light rare-earth elements resulted from a double sulfate precipitation, whereas a potassium ferrocyanide pr cipitation yielded a fraction enriched in yttrium. Precipitation with dimethyl phosphate yielded a fraction enriched in yttrium and heavy rare-earth elements. Enriched fractions were obtained with several solvent extraction systems. A system consisting of rare-earth nitrates, nitric acid, and tri-n-butylamine-3 methyl-2-butanone favored the separation of yttrium from the heavy as well as from the light rare-earth elements.

Jan 1, 1961

By A. L. Engel

This report describes laboratory-scale experimental treatment of six base-metal ore samples taken by engineers of the Bureau of Mines, Region II, while investigating ore deposits in California and Nevada. The information is of interest in developing the mining districts represented or when similar ores from other sources are being studied. Simple treatment methods were employed as far as possible. More complex treatments also were tried when necessary. The possibilities and limitations of the methods applied to the several ores are shown by the data herein reported.

Jan 1, 1960