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By A. A. Berk

Other Federal agencies have been coming to the Bureau of Mines for help with the purchase and utilization of fuel, largely coal, almost since the day the Bureau was created in 1910. The requests covered a wide range of fuel-economy problems and included boiler-water treatment after it became apparent that water-formed deposits on heating surfaces acted as insulators, decreasing heat transfer and impairing fuel efficiency. Dr. Ralph E. Hall, a Bureau of Mines physical chemist determined the reactions that cause adhering scale to form in boilers (7)2 and went on to introduce scientific principles into water treatment for scale prevention (8). Widespread publicity of these achievements increased the requests for help from Federal steam-generating plants. Since no other Federal agency (even those which were more directly concerned with testing water) wanted to provide boiler-feedwater service, the Bureau decided to continue to give requested help to Federal agencies, Later, the Congress endorsed such agency cooperation as an economy measure,

Jan 1, 1963

By L. H. Duschak, C. N. Schuette

In the years 1850 to 1923, the United States produced 2,426,000 flasks- (73,600 metric tons) of quicksilver worth $120,500,000. California yielded 2,195,000 flasks of this total; the remainder came from Texas, Oregon, Nevada, and A.rizona. Most of this metal has been extracted from low-grade ores, those containing less than 0.5 per cent mercury or 10 pounds per ton. The finished product or " virgin metal" is made at the mine and shipped in flasks. Quicksilver is unique in being the only metal that is liquid at ordinary temperature. Because of this and other physical and chemical properties, it is perhaps more indispensable to industry than any other metal. On the other hand, the quicksilver industry of the world is of vanishing significance" when compared to the major mineral industries with respect to quantity and value of product, capital invested, or the number of men employed. The peculiar value of quicksilver is due to the fact that in some of its applications no substitute is available and in others the substitutes would be unsatisfactory or extremely expensive. Scarcely a branch of science or industry fails to make some use of mercury or its compounds. As a detonator for explosives, mercury fulminate holds first place and in safety and reliability could be replaced only by the highly expensive silver fulminate.t vThrough its use in detonators and in the metallurgy of the precious metals quicksilver is of special importance to mining. In medicine,in the manufacture of electrical apparatus, the production of pigments and antifouling paints, and the general field of experimental science quicksilver is equally indispensable.

Jan 1, 1925

By Robert B. Hoekzema

The Bureau of Mines and U.S. Geological Survey completed a 4-yr (1979-82) mineral appraisal of the Chugach National Forest (CNF), AK. This report summarizes the Bureau's placer gold studies in the CNF. Placer mining from the mid-1890's through 1982 produced an estimated 133,800 oz of gold, of which two-thirds was produced prior to 1920. As much as 6,800 oz of placer gold was produced from 1979 to 1982. Most production came from Crow, Canyon, and Resurrection Creeks. Five types of placer gold deposits were identified in the CNF: (1) alluvial placers, (2) bench placers, (3) eluvial placers, (4) glacial placers, and (5) marine placers. Placer sampling indicated a potential for gold production from alluvial and bench placers associated with historically mined drainages such as Crow, Canyon, Resurrection, Sixmile, and Mills Creeks and from unmined drainages including the Avery, Kings, Snow, Copper, and Tasnuna Rivers and several smaller streams throughout the CNF. Results of fineness tests indicated that gold from the CNF ranges from 455 to over 950 fine. Subsequent investigations in drainages with anomalous placer sample values also identified previously unknown lode mineralization.

Jan 1, 1986

By J. P. Capp

This experiment, one of a series on underground gasification of coal, was an investigation by the Federal Bureau of Mines of hydraulic fracturing as a means of increasing the air acceptance of a coalbed to permit introducing combustion air and removing product gases. Specific objectives of the investigation included: (1) Fracturing a coalbed; (2) determining the distance the coal was physically affected; (3) ascertaining the effect of the fracture on air acceptance of the coalbed; and (4) gasifying the coal. The coal was fractured with a fluid consisting of 15,000 lb. of sand mixed with 10,000 gal. of fuel oil and 5,000 gal. of kerosine, injected at pressures up to 900 p.s.i.g. and rates up to 425 g.p.m. The oil served as the fracturing medium, and the sand as a propping agent to hold the fracture open. From the fracture point, (the place in the bed where the fluid was injected), the fracture extended 200 ft. or more along the face cleats, somewhat less along the butt. cleats, and was confined to the coalbed. At the fracture point, the bed accepted about 500 std. c.f.m. of air, which was an etghtyfold increase. Fracture effects were extensive, as airflow was noted from old mine workings and outcrops 600 to 800 ft. from the fracture point. It is probable the actual fracture was much less than 600 ft. and that normal coalbed permeability beyond the fracture limits was responsible for this flow. This indicated that effects of the fracture extended beyond the area of coal physically affected. Although no attempt was made to gasify coal more than 200 ft. away, these effects plus the natural permeability of the bed likely would permit combustion beyond the outer limit of the fracture. As these experiments continued for more than 2 years, and greater air acceptance due to the fracture was observed at the beginning of each test, it is apparent that the effects of the fracturing persist for a considerable time.

Jan 1, 1960

By Marilyn Biviano

(l)The direct economic costs to this nation resulting from a decision to embargo South African strategic and critical minerals imports are estimated at $1.85 billion per year.2,3 About 94 percent of these estimated costs are for two platinum-group metals (PGM's), platinum and rhodium. The estimated costs of a 5-year embargo beginning in 1988 for the strategic and critical minerals analyzed are presented in Table 1.4 (2)There are sufficient alternative world sources to South Africa for manganese, chromium, palladium, titanium, and vanadium to meet U.S. industrial demand in the event of an embargo. (3)Alternative world sources to South Africa for platinum and rhodium cannot meet U.S. industrial demand. Non-South African world supply sources can meet about 40 percent of domestic platinum consumption requirements and 50 percent of rhodium requirements. (4)As a result of the increase in prices for platinum and rhodium during the embargo, expansion of domestic platinum-group metals mining and secondary production is expected. During a five year embargo, domestic primary and secondary production expand and together satisfy about one-third of U.S. platinum requirements, one-third of U.S. rhodium requirements, and over one-half of domestic palladium requirements.

Jan 1, 1988

By E. P. Youngman

The mining law of British North Borneo is entitled " The Mining Ordinance , 1927. 113 The only mining regulation or rule available is " Rules 313 , 114 passed in accordance with article 26 of the ordinance of 1927. Before the passage of this legislation , the country had no specific law governing the granting of mineral rights , although the land law contained provisions relating to mining lands . The land ordinance of 19135 still controls in a few details . All references in this paper , unless otherwise specifically designated , are to the mining ordinance .

Mar 1, 1933

By Sam S. Taylor

Subsurface disposal of oil-field brines was practiced in Oklahoma on a limited scale as early as 1925. The technique of subsurface injection has been improved immensely and has been applied with varying success in many oil-producing areas in Oklahoma, and elsewhere. This method of disposal, however, is only one of several methods available to operators of oil-producing properties, but, in contrast with usual methods of handling brines on the surface it eliminates the damaging effect of mineralized water on fresh-water supplies, vegetation, and aquatic and other animal life. Other methods of brine disposal approved by regulatory agencies in some States include (1) impounding in impervious ponds and solar evaporation, (2) controlled diversion into surface waters, and (3) recovery of the mineral salts of the brine. In most, States where oil is produced regulatory bodies authorize the use of one or more of these methods of brine disposal. In Oklahoma, for example, the Oklahoma Planning and Resources Board of the Conservation Commission has been authorized to adopt whatever methods or means may be necessary to prevent contamination by mineralization of all potable waters within the State.

Jan 1, 1942

This Bureau of Hines report on underground mine communications addresses methods and equipment to meet the communication requirements of working sections and places of coal and metal-nonmetal mines. A review of the status of trapped miner detection is also presented.

Jan 1, 1977

By Bruce F. Grant

"INTRODUCTION The future of oil production in the part of the Appalachian region included in southwestern Pennsylvania; West Virginia, and southeastern Ohio is directly dependent on the maintenance of existing wells. This report presents an analytical study of the methods used in oil-well reconditioning in this area. The study is part of a research program designed to evaluate those means of stimulating oil production that can effectively and economically maintain present oil-production rates and make it possible to keep existing wells in operation. Well-reconditioning work was curtailed during the war; therefore, an abnormally large number of wells in the Appalachian Region is now in need of repair. Because the lubricant content of Appalachian crude: oils is high and the refined lubricating oils an; particularly suited to use in high speed, high-temperature engines, the demand for these crude oils during the war exceeds, the maximum rate of production obtainable under wartime operating conditions. Increases in operating, expenses, inability to meet war-time reconditioning costs, and inflexible price structures caused the abandonment of an alarming number of wells during the past 4 or 5 years.As a means of increasing regional oil-production rates, new drilling in the older fields for primary production generally is uneconomical because reservoir pressures in most of the fields have virtually been depleted and the production rates of newly drilled wells are small."

Feb 1, 1948

By Yael Miron

This report describes laboratory studies by the U.S. Bureau of Mines to determine the suitability of a static oxygen (OJ adsorption test for evaluating the self-heating tendencies of coals. Reliable minimum self-heating temperature (SHT) values from adiabatic oven tests were used as standards for comparison and evaluation. A suite of six coals was tested in the adiabatic oven and in sealed flasks. In the latter tests, both undried and dried samples, in a range of four particle sizes, were examined. Miniature pressure trans-ducers monitored pressures in the flasks, and gas samples taken at the end of the tests quantified all the gases present. An excellent correlation was found between the minimum SHT's and amounts of O2 adsorbed over a 7-day period for dried coals, independent of particle size. In addition, a good correlation was obtained between the minimum SHT's and pressure changes in the flasks at the end of the test for the same coals, also independent of particle size. Based on these results, the sealed flask test can be reliably used to determine the self-heating tendency of a bituminous coal sample.

Jan 1, 1990

By Clark P. Mangelsdorf

The report consists of two parts. In Part I is a state-of the-act study of roof truss technology as of January 1979. Included are a history of the truss concept, a review of analysis techniques, a record of hardware available and equipment used in its installation and numerous examples of user experience. Part II is concerned with a study of the role of friction in the behavior of a roof truss. The appendices include laboratory tests by the author.

Jan 1, 1979

By P. B. Grote

The report is concerned with the issue of the possible transfer of U.S. and other developed country deep ocean mining (DOM) technologies to developing countries. This subject is one of several major issues in current UN Law of the Seas negotiations. As background to the subject, the report provides a detailed critique of the various terms and conditions pertaining to technology transfer in recent negotiating texts. It also provides a description of the relevant DOM technology, sources of innovation, and methods of proprietary protection. Functional requirements for viable technology transfer are developed and used as a basis for the definition of alternative levels of programs and implementation approaches, including required changes in the negotiating text. The consequences of these technology transfer options on the various parties are investigated.

Jan 1, 1978

By Thomas M. Barczak

State-of-the-art longwall roof supports provide effective strata control, but failures of these support systems still occur. To identify failure mechanisms and the impact these failures have on the safety of the support system, the U.S. Bureau of Mines has been conducting research on shield mechanics in the Bureau's unique mine roof simulator, as well as field studies of in situ support loading and investigations of longwall failures, Three types of failures are discussed: (1) inadequate support capacity, (2) structural failure, and (3) instability. Hypothetical situations with proposed courses of action and case studies of actual longwall failures are described. This information is intended to assist the Mine Safety and Health Administration (MSEIA) and industry mining personnel in safety evaluations of longwall roof support systems.

Jan 1, 1989

A new personal respirable dust monitor developed by Rupprecht & Patashnick Co., Inc. in a multi-year project funded by the National Institute for Occupational Safety and Health (NIOSH) generated promising results in underground coal mine testing performed by NIOSH and industry representatives during the summer of 2003. The mine data showed that the personal dust monitor (PDM) performed similarly to co-located manual reference samplers for full-shift samples at all four underground coal mines at which the evaluation took place. The technology that forms the heart of the PDM, called the tapered element oscillating microbalance (TEOM system), is unique in its ability to collect suspended particles on a filter while simultaneously determining the accumulated mass with National Institute of Standards and Technology traceability. Because the monitor measures the true particle mass collected on its filter, its results do not exhibit the same sensitivity to water spray as do optically based measurement approaches. The technique achieves microgram-level mass resolution even in the hostile mine environment, and reports dust loading data on a continuous basis. Using the device, miners and mine operators have the ability to view both the cumulative and projected end-of-shift mass concentration values, as well as a short-term 15- or 30-minute running average. During underground mine trials in the summer of 2003, technical personnel used the readings from the PDM to identify and correct several abnormal dust generating scenarios. These events demonstrated the potential of the PDM to be used as an engineering tool to evaluate the effectiveness of various dust control strategies. In a separate evaluation performed by CONSOL Energy, Inc., the mine operator evaluated the benefit of a proposed new water spray-based dust control system. Engineers measured the dust concentration upstream and downstream of a production location under different dust control scenarios using two PDM units. By evaluating the change in the dust loading between the upstream and downstream monitoring sites, the company was able to determine in a few hours which hardware configuration would yield the greatest benefit to the workplace environment. BACKGROUND Measuring underground coal mine dust concentrations is an essential part of protecting miners' health. The U.S. Secretary of Labor and the Federal Advisory Committee on the Elimination of Pneumoconiosis among Coal Mine Workers has recommended that better monitoring of coal miner dust exposures be used as a method to improve miner health. In consultation with labor, industry, and government, NIOSH issued a contract to Rupprecht & Patashnick Co., Inc. (R&P), Albany, N.Y., to develop a one-piece PDM. The object was to miniaturize TEOM technology into a form suitable for a person-wearable monitor that would enable accurate end-of-shift dust exposure information to be available to miners. Furthermore, any person-wearable dust monitor should minimize the burden to the wearer by incorporating the monitor into the mine worker's cap lamp battery, with exposure data continually displayed during the shift to enable workers and management to react to changes in dust exposure. In the summer of 2003, NIOSH conducted extensive testing of the PDM to determine its laboratory and in mine performance. In addition, anecdotal information collected in the mines showed several occasions where miners were able to identify situations that produced high levels of respirable coal mine dust The PDM's response to unplanned changes resulted in action being taken to keep dust exposures as low as possible. In another case that demonstrated the PDM's versatility, a mine was seeking to find a better dust control solution on its longwall headgate stageloader. In this instance, the PDM was used as a diagnostic tool by the miners to quickly evaluate the control technology. [ ] HOW DOES THE PDM WORK? The PDM is configured to provide accurate respirable dust personal exposure information in a form that is as convenient to wear as a normal cap lamp (See Figure 1). Respirable dust exposure data displayed by the device has two main objectives: providing the miner and mine operator with timely values to avoid overexposure to dust, allowing them to make any necessary changes during the course of a work shift; and computing an accurate end-of-shift statistic for a miner's average respirable dust exposure. The mass sensor embedded in the PDM, holds the key to the accurate, time-resolved dust concentration measurements. The inertial, gravimetric-equivalent, mass measurement technique used in the device typically provides a limit of detection on par with that of the most sensitive laboratory-based microbalances.

By H. F. Yancey

The investigations described in this bulletin are confined to a study of the washing characteristics of bituminous coals. The major part of the work was conducted by the Bureau of Mines in cooperation with the Engineering Experiment Station of the University of Illinois and the State of Illinois Geological Survey Division between 1918 and 1924, in accordance with the provisions of an agreement between these agencies. The washing characteristics of coals from many of the important coal-producing fields of the Eastern and Central States were examined. The coals of the Pacific Northwest States and Alaska have been studied separately by McMillan and Bird of the Northwest Experiment Station of the Bureau of Mines at Seattle in cooperation with the College of Mines of the University of Washington.2 OBJECT OF INVESTIGATION The object of the investigation of coal preparation by the Bureau of Mines has been to promote the production of better prepared coal and to facilitate the correct selection and design of coal-preparation plants by obtaining as complete information as possible regarding the washability of the various types of American coals and the treatment best suited to each. In addition, some attention has been given to the development of new methods of washing coal. The work naturally divides itself into three rather distinct steps: (1) Development of a systematic method of examining and testing a coal; (2) classification of the American coals on a basis of the occurrence of the impurities associated with the coal in the beds; (3) examination of one or more representative coals of each type.

Jan 1, 1929

By J. H. East, D. Harrington

"INTRODUCTION Mining at its best is not a clean occupation for either surface or underground employees; and this applies alike to coal, metal, and non-metallic mines. The employees are handling minerals that have been blasted, or broken by some means and are subjected to mineral dust, whether it is coal, quartz, or talc. The employees usually wear clothes specifically adapted to the work in which they are engaged, and frequently these clothes are not suitable for use away from the mine. Many mines are wet, and employees must wear rubber boots to remain at least partly dry, and even on relatively dry mines, some parts of the mines usually have water falling from overhead, there are accumulations of water, or the floor or other surfaces are wet or muddy, Some mines are dusty, and the air-borne dust quickly settles on the clothes and body of the miner, especially, when he is working in confined areas, or in places that are hot, humid, or poorly ventilated. Most occupations around a coal tipple, anthracite breaker, or a mill at a metal or nonmetallic mine have their own problems of cleanliness as to skin or clothes or both. Mining in any of its phases is inherently dirty work, and the employees dress accordingly while at work.In the early stages of mining it was the custom or workers to wear their dirty clothes home and change there. This necessitated their going home after work in dirty clothes which were usually damp from perspiration or from contact with wet or muddy matelials or surfaces, and, in addition to being inconvenient this was a frequent cause of colds, pneumonia, other pulmonary diseases or, possible skin ailments. Men working in very wet mines found that it was more satisfactory to change into dry clothes in the boiler room at the mine after work and allow their wet clothes to dry overnight. The mining companies later provided the first of the so-called ""dry-houses"" which were heated but had, few, if any, conveniences, such as showers, lockers, or latrines. The miners changed into dry clothes after work, but would not bathe or ""clean up"" until they reached their homes. Later, progressive mining companies provided bathing facilities for the employees, and eventually the present modern wash and change houses were evolved. Unfortunately, many mines, still have no bathing accommodations, and many have only makeshift accommodations."

Dec 1, 1947

By T. J. Driscoll

Methane-air mixtures can ignite as a result of sparking or rubbing of materials, particularly by impact involving light alloys and rusted steel where an exothermic thermite reaction can occur. This report reviews the published literature and describes a new method utilized by the Bureau of Mines for studying the processes occurring during collisions of light metals with rusted steels. The method involves measuring the spectra of sparks and explosions in methane-air mixtures using a photodiode array. Initial results obtained using magnesium and aluminum alloy 6061-T651 projectiles striking rusted steel are reported. These results indicate that the continuous parts of the spectra show a larger intensity for incendive sparks compared with nonincendive sparks, with the largest relative change in the higher energy, ultraviolet region. An unexpected shift of the intensity maximum for the continuous parts of the spectra towards the infrared region was observed for the more incendive sparks. Evaluation of rusted steel samples with electron microscopy, energy-dispersive X-ray spectrography, and Auger electron spectroscopy after they had been impacted by aluminum alloys indicated that aluminum was transferred to the steel in the form of islands that became larger as a function of increasing projectile velocity.

Jan 1, 1982

By C. A. Herbert

Information Circular 6746 reviewed the fatalities in Indiana coal mines. for the fiscal year October 1, 1951 to September 30, 1933. Since then Indiana has changed its fiscal year to the period July 1 to June 30, but as most statistical data on accidents are arranged according to calendar years, the data in this paper are for the last 3 months of 1932 and the calendar year 1933, rather than for the new Indiana fiscal year. Tables 1 and 2 list the fatalities in Indiana coal mines3/ by cause and occupation for the last 3 months of 1932 and for the calendar year 1933. The fatalities for the small wagon mines employing fewer than 10 men are separated from those employing 10 or more men to call attention to the ex- tremely high fatality rate in small mines, largely because the State mining law does not apply to them nor do they come under the jurisdiction of the Indiana mine inspectors; as a result health and safety conditions are ex- tremely bad. During the last 3 months of 1932, 5 (approximately 42 percent of the total) fatalities occurred in the small mines, while for the calendar year 1933, 12 (approximately 32 percent) of the fatalities occurred in them. The Indiana Division of Mines and Kining estimates that these small mines have an annual production of approximately 325,000 tons, or about 4.5 percent of the total coal-mine production of the State. In other words, for these small mines the fatality rate per tons mined during 1933 was about 10 times as great as for the mines employing 10 or more men. Another lamentable feature in connection with the fatalities in small mines is that very few carry any compensation insurance and the owners are not worth enough financially for dependents of victims to collect anything under the common law; as a result, the dependents of those killed usually are left penniless and subjects of public charity.

Feb 1, 1935

By S. P. Sandoval

Previous research by the U.S. Bureau of Mines demonstrated that nonionic surfactants increased the leaching rate of copper in the flask leaching of chalcopyrite with ferric sulfate if sufficient ferric sulfate was present. This research was continued by the Bureau in Part 2 to further explore the application of nonionic surfactants to the dump leaching of chalcopyrite. A polyoxyethylene lauryl ether was selected as the superior nonionic surfactant tested at 25° and 50° C. The addition of the surfactant increased copper leaching by 116 pct at 25° C and 1.0 pct solids and by 61 pct at 50° C and 0.5 pct solids at Fe 3+ concentrations greater than 1 g/L. At 0.1.0 g/L Fe 3+ and below, the addition of the surfactant produced as much as a 35 pct decrease in leaching. Each of the nonionic surfactants studied was found to be heavily adsorbed by a typical chalcopyrite ore, which poses a serious barrier to the application of nonionic surfactants in an actual chalcopyrite dump.

Jan 1, 2010

By Charles B. Carpenter

The New Hope field was selected for study by; Bureau of lanes engineers because many problems met by, the operators during development and operation were unique to petroleum-engineering experience. Solving these problems is believed to have doubled the ultimate recovery of oil from the field. Since the discovery well was 'completed, in April 1943, an oil-productive area of 4,950 acres- has been delineated by the drilling of 64 wells, four of which were dry holes. Four oil-bearing reservoirs - the Bacon oolitic limestone, and the Hill, Pittsburg) and Elledge sandstones, all, in the Trinity group of the Lower Cretaceous series-- have been penetrated at depths ranging from 7,300 to 8,100 feet. Three of these reservoirs were found to be closed-type or solution gas-drive reservoirs, and one - the Hill - was an open-type or water-drive reservoir. During the course of the study, the Tide Water Associated, Oil Co. and -Seaboard al Co. of Delaware made available to the writers all well records, electric logs; and coring, production,, and pressure data. The ,writers performed Certain field and laboratory- tests on cores of ,the reservoir racks and' samples -of the reservoir Oils. Analyses of cores from the four reservoirs showed average .porosities ranging from 10 to 18 percent, average permeabilities of 17 to 297 millidarcys, and -average 'connate water contents ranging from 25.4 to 30.6 percent. Subsurface and recombined samples of reservoir oils indicated that the oils in the Bacon Hill, and Pittsburg reservoirs contained ,206 to 422 cubic feet of gas in solution per barrel initially, and that the, reservoir oils were undersaturated with gas. No samples' of oil from the Elledge reservoir were analyzed, and because of meager data this reservoir was not studied in detail. 4 The presence of free 'gas' or a' gas cap, however, indicated that the oil in the Elledge reservoir was saturated with gas. The rapid decline in pressures in- the' four reservoirs during the 'first year of operation alarmed the operators and provoked them to investigate the reservoir conditions to determine the cause.

Jan 1, 1949