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By Michael D. Fenton

The very modest-sized mineral industry of Afghanistan was burdened for another year with problems of internal strife occassioned by the presence of Soviet armed forces. Despite this, production of the few traditional commodities continued, and the mineral industry moved to develop additional mines and plants for both traditional and new products with considerable technical and construction assistance from the U.S.S.R. Among the limited range of mineral commodities for which production was reported, there were no startling changes between 1984 and 1985. Production of both coal and natural gas advanced only slightly, despite substantially higher 5-year plan goals, and cement output was down marginally. Probably the most significant development in 1985 was the Possibility that mine and/or smelter production of copper was initiated during the year.

Jan 1, 1987

By L. M. Demers, D. C. Kuhn

The alveolar macrophage (AM) responds to stimuli such as coal mine dust by releasing inflammatory mediators such as cytokines, growth factors. reactive oxygen species. and eicosanoids. Eicosanoids are synthesized by°AM through the action of cyclooxygenase and lipoxygenase enzymes and serve to modulate the proinflammatory function of this cell as part of the lungs' host defense mechanism. Reactive oxygen species can be generated by AM as a by-product in the biosynthetic pathway of the prostaglandins. AM produces primarily prostaglandin E2, thromboxane A2, and leukotriene B4 as part of the cellular response to an inflammatory stimulus. There is evidence to suggest that eicosanoid production by AM is functionally linked to both surface interaction with mine dust particles like silica and by the phagocytosis of the dust particle itself. In this report, we examined the effects of an antioxidant, vitamin E. on dust-induced synthesis of PGE2 and TXB2 in vitro and in vivo by AM obtained by bronchoalveolar lavage from rats. We also looked at the effects of the surface of silica particles on AM eicosanoid biosynthesis under conditions of calcination, a process that removes exposed hydroxyl groups from the surface of silica particles, thus reducing the likelihood of soluble hydroxyl radical formation. Treatment of AM with vitamin E in vivo and in vitro reduced the augmentation in eicosanoid production usually observed when AM are exposed to mine dusts. These results suggest that vitamin E may effectively reduce the inflammatory and fibrotic response produced by inhalation of mineral dust through an antioxidant mechanism. Silica that has been chemically altered by calcination was unable to activate AM eicosanoid production in vitro when compared to untreated, freshly fractured silica. These findings suggest that the mechanism by which dust particles can activate AM eicosanoid release may involve interaction of surface and/or soluble factors with the cell membrane. Taken together, these studies point to the involvement of AM eicosanoid production as part of the proinflammatory response of this cell to occupational inhalation of mineral dust. - Environ Health Perspect 102(Suppl 10):97-100 (1994)

Dec 1, 1995

By S. E. Khalafalla

In support of its goal to maintain an adequate supply of minerals to meet national economic and strategic needs, the Bureau of Mines has investigated a novel hydrometallurgical system with sulfur dioxide. Differential leaching with dissolved SO2 of manganese, nickel, and cobalt from their hydrous oxides was found to be very rapid and efficient--almost instantaneous and quantitative. In this method a given weight of mixed oxides previously ground to minus 200-mesh is slurried with a leach solution containing a specified quantity of dissolved SO2 for 10 minutes at room temperature and ambient pressure. An empirical leaching parameter, R, is defined as the ratio of the number of SO2 moles in the leaching solution to the weight of the metal oxide charge. Plots of the variation of metal extraction with the ratio R generate a series of sigmoidal-shaped curves, each of which is characteristic of a specific metal extraction. A threshold value of R is required to initiate the leaching of a given metal from the mixed oxides. Once this threshold is reached, the metal recovery can increase to more than 95 pct in very short times. For increasing values of R, the extractability of various metals by SO2 follows the order: Mn > Ni > Co >> Fe, Al, Cu. Differences in the threshold R values permit a variety of metal separations to be made simply by adjusting the quantity of SO2 in the contacting solution. Success in this leaching system depends upon comminuting the sea nodules to less than 0.149 mm (100-mesh). Above this critical size, leaching is slowed due to the inaccessibility of inner particle reacting groups to the SO2 leaching agent. This results in nonselective extraction and less extraction of preferred metal values. At or below 0.149 mm, leaching by SO, is possible with all its attributes of selectivity, sensitivity, and rapidity. Leaching with HC1 solutions of the same pH level as dissolved SO2 yielded mixed, slow, and incomplete metal extractions. This observation rules out any interpretation based on hydrogen ion as the leaching agent. The leaching curves resemble the complexometric titration curves of heavy metals with specific coordination species.

Jan 1, 1981

By C. A. Komar

Renewed interest in the underground gasification of coal evolves from comprehensive studies of earth fracture systems that indicate that the movement of fluids can be controlled in the coalbed. In particular, directional property studies of natural microfissure occurrence, permeability, ultrasonic velocity, tensile strength, and orientation of intervals of inherent rock weakness, together with geologic structure setting and fracture trace analysis, can predict the gaseous flow paths in the coalbed. Having this information, the dominant direction in which gases generated and/or liberated by heat would move can be determined so that appropriate well patterns can be developed. Together with advances made in drilling technology that permit long horizontal holes to be drilled through the coal seams, tests can be conducted to determine whether directional control will permit devolatilization of the coalbed and gasification of the remaining hot coke in a systematic manner to produce a low-Btu gas suited for the generation of electricity.

Jan 1, 1973

By T. L. Joseph

The size and accessibility of the Minnesota manganiferous iron ore deposits make them attractive as a potential source of erromanganese, which is essential in the production of steel. For several years the Bureau of Mines has been conducting experiments to determine the feasibility of producing ferromanganese from these ores by a three-step process which involves (1) the smelting of the ores in the blast furnaoe to produce a high-phosphorus spiegel; (2) the treatment of the spiegel produced from step 1 in an electric or open-hearth furnace to separate the manganese from the phosphorus and the iron; and 3) the smelting of the high-manganese slag from step 2 to produce forromanganese. The details of the first two steps of the process and the results of tests with the experimental furnaces Lave been given in previous reports.5 The m$ or part of the experimental work on the second step has been conducted in a half-ton open-hearth furnace. Some preliminary tests showed, however, that the electric furnace has some distinct advantages over the open hearth for producing, from high-phosphorus spiegel, a slag containing from 45 to 55 per cent manganese and phosphorus and iron in amounts required for ferro-grade ore. The electric furnace tests described in this paper were made to get more information as to the possibilities of the electric furnace in connection with this problem and to study the fluxing effect of alumina on high-manganese slags. Herty, Conley, and Royer have reported' results of laboratory tests which showed that slags containing from 60 to 75 per cent MnO, from 8 to 10 per cent S102, and small amounts of CaO MgO, and FeO, were sufficiently fluid at 1,450° to 1,550° C. to pour readily if 12 to 14 per cent alumina was present. With a normal A1203 content resulting from the A1203 in the

Jan 1, 1931

Southeast Alaska's mining industry has come to life after nearly 50 years of relative dormancy. Commencement of operations of the Greens Creek Mine in 1989 marked a turning point in the industry as the first large scale mining operation in the region since closure of the Alaska-Juneau Mine in 1944. The Greens Creek Mine is now the nation's largest silver producer. Other large scale mining projects are now on the drawing board, including development of the Kensington Mine and reopening the Alaska-Juneau Mine, which could become North America's largest underground gold mine. The region's mining industry includes more than these large scale projects, however. For example, a significant level of mineral exploration occurs each summer in Southeast Alaska. In addition, mining operations in British Columbia and Yukon Territory are generating jobs and income in Southeast Alaska.

Jan 1, 1992

By John J. Sammarco

Mining, traditionally a low-tech industry, is now utilizing surprisingly complex programmable electronic (PE) systems. The functional safety of PE-based mining systems is an international issue and concern. From 1995 to 2001, there were 11 PE-related mining incidents reported in the U.S. and 71 PE-related mining incidents reported in Australia. These incidents are due, in part, to unprecedented levels of system complexity. The National Institute for Occupational Safety and Health (NIOSH) is addressing this issue of system complexity by conducting research to develop a quantitative complexity assessment methodology based on Normal Accident Theory (NAT). The methodology models the behavioral interactive complexity at the level of system requirements. A graph-theoretical approach is used for creating quantitative metrics from Software Cost Reduction (SCR) dependency graphs. This complexity assessment methodology will help realize simpler, safer systems that will be easier to validate and verify. The methodology will benefit mining and other industries as well.

By J. G. Kirby

The total number of petroleum refineries in the United States decreased during 1951, while the total crude-oil charging capacity continued to increase. There were 350 refineries as of January 1, 1952, compared with 357 a year earlier, according to the annual Bureau of Mines capacity survey. A gain of 369,241 barrels in daily refinery crude through-put capacity during 1951 brings the total to 7,332,885 barrels daily. The capacity of the average refinery to process crude-oil was 20,951 barrels daily, an increase of 1,445 barrels daily over the previous year. Capacity added in the Texas Gulf district accounted for 36 percent of the total increase; the Indiana-Illinois-Kentucky district, 23 percent; the East Coast district, 19 percent; the Oklahoma-Kansas district, 12 percent; and the Texas Inland district, 11 percent. The California district was the only one reporting a decline in crude-oil refining capacity, the total being 14,200 barrels daily below the previous year. Reported as under construction January 1, 1952, was an additional crude-oil capacity of 282,680 barrels daily, an increase of 77 percent over the January 1, 1951, total of 160,100 barrels. The capacity now building is for the expansion of existing facilities, since no new plants had been begun as of the first of the year. Three or four companies have plans to build refineries in the Williston Basin area of North Dakota, but no definite locations or dates when construction will begin have been announced.

Jan 1, 1952

By W. H. Kerns

The Critchfield manganese deposit, Huntingdon County, Pa., was investigated by the Bureau of Mines in October 1942. Iron ore was mined from an open cut just southeast of the manganese deposit about 80 years ago. The Critchfield Sand & Feldspar Co. was operating (1942) a clay-mining and beneficiation plant northeast of the manganese deposit. The Bureau completed six rotary bucket-drill holes and three hand-auger holes, aggregating 370 feet on the deposit. This report describes the work performed and presents the results obtained.

Jan 1, 1948

By M. M. Fine

This report presents the results of laboratory mineral-dressing investigations by the Bureau of Mines of 14 individual or composite character samples from deposits in the Batesville manganese district. It will be noted that some concentrates have met or approached analytical specifications for metallurgical manganese ore although great variations in both physical and chemical composition from once deposit to another make each a new problem. In most cases it is evident that a substantial loss of manganese has occurred in the various slime and tailing products. An important aspect of this work is the research being conducted on manganese-bearing limestones. Recent reconnaissance indicates that this resource constitutes one of the major domestic reserves of manganese. Laboratory study has shown that ferrograde concentrates can be recovered from samples of manganese-bearing limestones from two properties. Research on samples from other areas is still underway.

Jan 1, 1957

By Arne Landsberg

Experiments were made with a batch reactor to determine the effect of gas pressures, temperature, and gamma radiation intensity on the reaction CO + Ch ? COC12. The equation, [dp = 0.0110 (1 - 0.01t) (PCOI)1/2 PC12] where [dP] is the change of pressure of phosgene with time (atm/hr), t is the temperature (°C), PCO and PC12 are the reactant pressures (atm), and I is the radiation intensity (r/hr), was found to best fit the data. Oxygen and a large ratio of reactor surface to volume retarded the reaction, but inert gases had no effect. A low-temperature reactor system is proposed to take advantage of the conditions which give a high reaction rate with gamma radiation and a simple scheme of product purification.

Jan 1, 1970

By T. H. Davis

Twelve laboratories from the Western United States and Canada participated in radon progeny intercomparison measurements at the U.S. Bureau of Mines radon calibration facility in March 1987. The participants intercom pared grab-sampling and automated equipment methods at high and low concentrations of radon progeny and condensation nuclei (CN). The objective of this intercomparison was to determine if the measurement procedures and equipment of the North American facilities are equivalent. The sampling results showed good agreement among all participants. The standard deviation for the working level measurements was less than 3.5% for 1.70 working level (WL) and less than 8.8% for 0.21 WL. This relatively good agreement was achieved by using alpha standards calibrated by National Bureau of Standards (NBS) and by closely checking and monitoring airflows.

Jan 1, 1989

By E. J. Gleim

To make a thorough survey of a coal mine in order to eliminate hazards, the competent safety engineer must be familiar with mere than one branch of engineering. It is essential that he know the properties of mine gases and the methods of detecting them, as well as hew to prevent dangerous as accumulations. It is also essential that he understand the action of overlying strata when the coal is removed, and the proper methods of protection by timbering or other suitable means of support. He must know the value of protective clothing in reducing injuries and mast be informed as to the correct handling and use of explosives to avoid premature blasts, misfires, and ether failures in blasting practice. He must understand hew to operate locomotives and cutting, loading, and various other types of machines to be able to recommend effective safeguards for protecting the men who use them in addition to being informed as 'to these and many ether activities connected with the mining of coal, he must net overlook electrical engineering if he wishes to combat the fire, shook, and ignition hazards attendant upon the use of electrical machinery and circuits in and around the mine intelligently. There are many points relating to safely in the selection, maintenance, and use of electrical circuits and equipment that are perfectly obvious to the electrical engineer but perhaps are not se evident to those not trained in this particular branch of engineering. Engineers of the U.S. Bureau of Mines who have made a special laboratory study of electricity as related to safety in minus haw e also made inspections of electrical installations at a large number of bituminous mines. These inspections have revealed practices and conditions that not only do not contribute to safety but that add nothing to efficiency and economy in the operation of the mine.

Jan 1, 1936

By Brian R. Zelenka

The Bureau of Mines (Bureau) reviewed all available information regarding geologic and depositional processes contributing to potential coastal and offshore platinum group metal (PGM) placer deposits around the Goodnews Bay Mining District. The Bureau found that favorable environments for PGM along with gold and chromite enrichment include: (1) buried paleofluvial channels; (2) recent paleofluvial channels with little marine sediment overburden, (3) beach deposits, particularly in the upper swash zone and near back beach environments; (4) paleostrand lines; (5) shoal lag deposits inside the mouths of Goodnews and Chagvan bays; and (6) bases of far offshore tidal ridges which may represent reworked glacial deposits. Limited geologic and compositional (assay) data prevent determination of deposit size and grade of PGM mineralization for each deposit class. Future geologic sampling requirements for demonstration of identifiable offshore and beach PGM-bearing placers are discussed. Beach and offshore sampling programs conducted by the Bureau in 1986 will contribute additional information providing verification of specific deposit classes.

Jan 1, 2011

The principal activities of the Bureau of Mines Explosives Research Center from July 1, 1963 to June 30, 1964 are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1964; in general, the research reported in these publications antedates the report period. Part 3 describes a short-term investigation into safety problems associated with shipping of molten sulfur; this investigation is not at present destined for publication elsewhere.

Jan 1, 1965

By George S. Rice

"It is well known that the lost coal left in the ground in mining, under such conditions that recovery is practically impossible, constitutes a large proportion of the coal in the beds worked. A recent estimate, in a paper on ""The World's Fuel Supply"" presented by Prof. L. P. Breckinridge, of Yale University, before the Annual Meeting of the. American Society of Mechanical Engineers, places the average loss in bituminous coal mining as one-third left in the ground.The bald statement that there is a loss of one ton of coal for every two recovered may seem to those not familiar with coal mining to imply inexcusable and wanton waste. Perhaps a better way of expression is in terms of total recovery rather than in terms of losses. Many mine superintendents and mine owners will readily concede that their total recovery may be only 60 to 75 per cent, but to state that they are wasting 25 to 40 per cent arouses antagonism. The suggestion is of willful waste, whereas the majority of the operators try to the best of their ability to get a high recovery under the adverse and complex conditions that confront them. These involve natural, commercial, and labor conditions, and the requirement in many cases of boundary pillars under railroads and buildings, which may be called for in the deed or lease, or in the absence of specific exemption in the deed or lease, the common law requirement that a surface owner is entitled to the support of the surface."

Apr 1, 1921

Commodities statistics and other information are available through the following three systems: Internet Access: To acccess the USBM Gopher server on Internet, connect to: gopher.usbm.gov port 70, using gopher client software. Or contact the Systems Administrator for technical questions: Matt Klevemann, 412-892-6499 (klevemmc@miner.usbm.gov) These USBM materials are available on Internet, with more to come in the future: Publications and other research findings, including this bimonthly publications list, newsletters, tech transfer updates, enviromental technology research, health and safety information. USBM software products Media materials and speeches. Mines Data: Computer bulletin board. Log on via modem through 202/501-0373, or call 202/501-0406 for technical assistance. Mines FaxBack. Return fax service. 1. Use the touch-tone handset attached to your fax machine's telephone jack. (ISDN [digital] telephones cannot be used with fax machines.) 2. Dial 202/219-3644. 3. Listen to the menu options and punch in the number of your selection, using the touch-tone telephone. 4. After completing your selection, press the start button on your fax machine.

Jan 1, 1995

By Terry J. Close

The Anaconda Pintlar Wilderness has a significant mineral resource potential. Five deposits have resources totaling about 180,300 tons (163,600 t) containing silver, copper, lead, gold, and zinc. Another 11, not sufficiently exposed to allow resource estimates, may have additional mineral potential. No placer deposits are indicated. There is little potential for the production of sand, gravel, or stone; alternate sources are closer to markets. No oil, gas, uranium, or geothermal energy sources are known to be present.

Jan 1, 1982

By R. L. Grant

Study of the ignition of firedamp by explosives and the phenomena that underlie it is one of the long-term investigations of the Bureau of Mines. This report is the third in e series by the Explosives Branch summarizing the progress made at Bruceton in this study. The first paper described preliminary work on small, carefully controlled cannon shots the second discussed the results of suspended shots.5/ In this paper, experiments are described and interpreted that extend and support the concept of ignition presented previously. ACKNOWLEDGMENT The authors wish to thank Bernard Lewis, former chief, Explosives and Physical Sciences Division, and Guenther von Elbe, former chief, Physical Sciences Branch, Explosives and Physical Sciences Division, for their guidance and constructive interest.

Jan 1, 1954

By Richard J. Leary

The inputs of capital and labor to support future iron ore production were developed by the Bureau of Mines from projections of iron demand and estimates of capital and labor requirements. Trends in technologic change and the organization of production were analyzed. Labor requirement schedules for iron ore mining and beneficiating were constructed from aggregate inter-temporal trends and 1970 cross-sectional analysis of mines and mills. A sup-ply schedule of the capital requirement for mine-mill-pellet plants was developed from U.S. and Canadian experience. The structure of demand for iron to the year 2000 was examined as well as the availability of resources. Projections of capital and labor requirements to 2000 were constructed under two international patterns of iron ore supply to the United States. The most likely model is for a continuation of the 70 percent United States-30 percent foreign shares, expanding at an average 2.0 percent growth rate to 2000, and supported by a cumulative gross capital investment of $3.8 billion constant 1967 dollars and a labor force in the United States of 29,800 by 2000. The information content of projections is discussed, and the possible effects of international forces on supply are considered. A generalized methodology for estimating capital and labor requirements in other mineral industries also is included.

Jan 1, 1975